Home |
Search |
Today's Posts |
|
Metalworking (rec.crafts.metalworking) Discuss various aspects of working with metal, such as machining, welding, metal joining, screwing, casting, hardening/tempering, blacksmithing/forging, spinning and hammer work, sheet metal work. |
Reply |
|
LinkBack | Thread Tools | Display Modes |
#1
Posted to rec.crafts.metalworking
|
|||
|
|||
Learning industrial robotics, any favorite robots?
Looking at the jobs available for PLC and automation, one area that I need
to strengthen is in Robotics. The plant where I work uses some robots but the work is all outsourced. We are shown how to jog the robots out of a jam and restart it, but that's about it. So I was thinking about looking for a bargain industrial style robot, something I can use to learn about robotics. Any favorites as far as friendly companies, online documentation, etc.? I don't want to buy a $1500 bargain robot only to find out there is no available documentation or it requires high $$$ software or something. I'd like it to be something with demand like Fanuc or ABB or other major industrial robotics manufacturers. RogerN |
#2
Posted to rec.crafts.metalworking
|
|||
|
|||
Learning industrial robotics, any favorite robots?
On Thu, 25 Jul 2013 23:42:26 -0500, "RogerN"
wrote: Looking at the jobs available for PLC and automation, one area that I need to strengthen is in Robotics. The plant where I work uses some robots but the work is all outsourced. We are shown how to jog the robots out of a jam and restart it, but that's about it. So I was thinking about looking for a bargain industrial style robot, something I can use to learn about robotics. Any favorites as far as friendly companies, online documentation, etc.? I don't want to buy a $1500 bargain robot only to find out there is no available documentation or it requires high $$$ software or something. I'd like it to be something with demand like Fanuc or ABB or other major industrial robotics manufacturers. RogerN Its getting to be, A LONG TME AGO, but I made four GM Fanuc robots do my bidding for a couple years. The control language was a computer language most similar to Pascal (maybe nobody has heard of that anymore) I went to GM for training and they also had a computer program with robot simulator so you could test your code at your desk. Anyway, 20 years ago, I found writing programs for robots to be easier than PLC programs. If you are interested, my son has a scrap welding robot he'd be willing to sell. Karl |
#3
Posted to rec.crafts.metalworking
|
|||
|
|||
Learning industrial robotics, any favorite robots?
"Karl Townsend" wrote in message
... snip Its getting to be, A LONG TME AGO, but I made four GM Fanuc robots do my bidding for a couple years. The control language was a computer language most similar to Pascal (maybe nobody has heard of that anymore) I went to GM for training and they also had a computer program with robot simulator so you could test your code at your desk. Anyway, 20 years ago, I found writing programs for robots to be easier than PLC programs. If you are interested, my son has a scrap welding robot he'd be willing to sell. Karl Where I used to work we had a couple of Asea (now ABB) robots that I got working. I just followed the instructions for programming and moved it point to point storing the points, then the robot would repeat the moves. They eBayed them after a while, sold for $100, I would have bid but I didn't watch the auction, I figured 2 working Asea robots would be way over my budget. Jogging to a few points and programming those points was the limit of my experience with robot programming. Does the welding robot have the controller? I'm wondering about shipping, how far away and any idea on weight? For learning purposes, I'm looking at some little robots on eBay, like they use in schools for robotics training. I'd prefer a more industrial robot but finding something low cost that works nearby is the trick. I could take a college course with robotics but I can learn more by buying a robot and reading the instructions, doing some projects. RogerN |
#4
Posted to rec.crafts.metalworking
|
|||
|
|||
Learning industrial robotics, any favorite robots?
....
Does the welding robot have the controller? I'm wondering about shipping, how far away and any idea on weight? For learning purposes, I'm looking at some little robots on eBay, like they use in schools for robotics training. I'd prefer a more industrial robot but finding something low cost that works nearby is the trick. I could take a college course with robotics but I can learn more by buying a robot and reading the instructions, doing some projects. RogerN Other than moving points, the robot waits for inputs, and fires outputs. Programming is the simple part. My son's robot and controller would weigh maybe 1000 lbs. so shipping would be the main cost. send me your email if you're serious karltownsendATembarqmail.com |
#5
Posted to rec.crafts.metalworking
|
|||
|
|||
Learning industrial robotics, any favorite robots?
On 26/07/13 05:42, RogerN wrote:
Looking at the jobs available for PLC and automation, one area that I need to strengthen is in Robotics. The plant where I work uses some robots but the work is all outsourced. We are shown how to jog the robots out of a jam and restart it, but that's about it. So I was thinking about looking for a bargain industrial style robot, something I can use to learn about robotics. Any favorites as far as friendly companies, online documentation, etc.? I don't want to buy a $1500 bargain robot only to find out there is no available documentation or it requires high $$$ software or something. I'd like it to be something with demand like Fanuc or ABB or other major industrial robotics manufacturers. RogerN Maybe not what you had in mind but you might find it amusing http://www.youtube.com/watch?v=FU-tuY0Z7nQ . From the British comedy series Not the Nine O'clock News. |
#6
Posted to rec.crafts.metalworking
|
|||
|
|||
Learning industrial robotics, any favorite robots?
replying to RogerN , passerby wrote:
regor wrote: So I was thinking about looking for a bargain industrial style robot, something I can use to learn about robotics. Any favorites as far as friendly companies, online documentation, etc.? I don't want to buy a $1500 bargain robot only to find out there is no available documentation or it requires high $$$ software or something. I'd like it to be something with demand like Fanuc or ABB or other major industrial robotics manufacturers. Perhaps start with something that's more geared towards learning? Like this: http://youtu.be/ov0SJJt2PhY Lookup Scorbot (a.k.a. Eshed Robotech, Intelitek, Depco) - you can start with an ER-III which is almost like a toy (but has all the functionality of a "proper" industrial robot) and, if that's not enough, progress to ER-VII (almost industrial - perhaps used somewhere in light industry) and then onto ER-9, an actual industrial robot. There's a ton of info online and there are quite a few on eBay at any given time, all within $300-$400 range, and sometimes have add-ons like conveyors, linear screw stages and rotary tables. Can definitely outfit the whole lab for under $1000 -- posted from http://www.polytechforum.com/metalwo...ts-580710-.htm using PolytechForum's Web, RSS and Social Media Interface to rec.crafts.metalworking and other engineering groups |
#7
Posted to rec.crafts.metalworking
|
|||
|
|||
Learning industrial robotics, any favorite robots?
On Thu, 25 Jul 2013 23:42:26 -0500, "RogerN"
wrote: Looking at the jobs available for PLC and automation, one area that I need to strengthen is in Robotics. The plant where I work uses some robots but the work is all outsourced. We are shown how to jog the robots out of a jam and restart it, but that's about it. So I was thinking about looking for a bargain industrial style robot, something I can use to learn about robotics. Any favorites as far as friendly companies, online documentation, etc.? I don't want to buy a $1500 bargain robot only to find out there is no available documentation or it requires high $$$ software or something. I'd like it to be something with demand like Fanuc or ABB or other major industrial robotics manufacturers. RogerN ======================== While we all like to use our own "stuff," you would most likely be far ahead to check if any of the community colleges or vo-techs in your area have a robotics class or two, You can learn on their equipment, the learning is structured, and you are "net working." In most cases you can sign up for single classes with the consent of the instructor, but most likely these will be non-credit [toward degree or certificate]. Also check with your local job placement office as all or part of the tuition/fees/books may be covered. |
#8
Posted to rec.crafts.metalworking
|
|||
|
|||
Learning industrial robotics, any favorite robots?
On 2013-07-26, Karl Townsend wrote:
Its getting to be, A LONG TME AGO, but I made four GM Fanuc robots do my bidding for a couple years. The control language was a computer language most similar to Pascal (maybe nobody has heard of that anymore) I went to GM for training and they also had a computer program with robot simulator so you could test your code at your desk. I remember Pascal, and I used it to write a serious suite programs -- but it is not really a good choice for such. It was designed as a teaching language, to make it difficult for you to engage in bad programming habits. But in the process, it makes a lot of things awkward to do. (This was a version of ISO standard Pascal. I think that Borland's turbo Pascal, and UCSD Pascal were a bit more forgiving, but I never used them. Anyway, 20 years ago, I found writing programs for robots to be easier than PLC programs. I wounder how a machine control program which resembles Pascal would be to work with. Enjoy, DoN. -- Remove oil spill source from e-mail Email: (KV4PH) | Voice (all times): (703) 938-4564 (too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html --- Black Holes are where God is dividing by zero --- |
#9
Posted to rec.crafts.metalworking
|
|||
|
|||
Learning industrial robotics, any favorite robots?
On 7/25/2013 11:42 PM, RogerN wrote:
Looking at the jobs available for PLC and automation, one area that I need to strengthen is in Robotics. The plant where I work uses some robots but the work is all outsourced. We are shown how to jog the robots out of a jam and restart it, but that's about it. So I was thinking about looking for a bargain industrial style robot, something I can use to learn about robotics. Any favorites as far as friendly companies, online documentation, etc.? I don't want to buy a $1500 bargain robot only to find out there is no available documentation or it requires high $$$ software or something. I'd like it to be something with demand like Fanuc or ABB or other major industrial robotics manufacturers. RogerN My favorite robot was Rhoda, as played by Julie Newmar on the show "My Living Doll". David |
#10
Posted to rec.crafts.metalworking
|
|||
|
|||
Learning industrial robotics, any favorite robots?
"DoN. Nichols" wrote in message
... I wounder how a machine control program which resembles Pascal would be to work with. Enjoy, DoN. The semiconductor test stations I worked on used a DEC dialect of Pascal, with a few Assembly hardware drivers. Programming test routines wasn't difficult as long as we paid close attention to variable typing, which meant bits and short integers in that application. We designed the hardware registers to mesh cleanly, like one status bit per byte rather than grouping and masking them. I've written a fair amount of hardware interfacing code in QBasic, which is part way between Pascal and C, with the structure and typing available but not as mandatory, and a single level of pointers that enables reckless variable abuse such as embedding a machine language interrupt routine as a String. I really liked having GOTO for exception handlers so they didn't clutter the main DO Loop structure. I wasn't about to ask the professor for formal permission to do an emergency shutdown. The last step in the test station's troubleshooting procedure gave the software manager's home phone number. He wasn't too happy when National Semiconductor called him at 3AM Eastern time. jsw |
#11
Posted to rec.crafts.metalworking
|
|||
|
|||
Learning industrial robotics, any favorite robots?
"David R. Birch" wrote in message
... My favorite robot was Rhoda, as played by Julie Newmar on the show "My Living Doll". David She was my favorite Catwoman, too. |
#12
Posted to rec.crafts.metalworking
|
|||
|
|||
Learning industrial robotics, any favorite robots?
"DoN. Nichols" wrote in message
... On 2013-07-26, Karl Townsend wrote: Its getting to be, A LONG TME AGO, but I made four GM Fanuc robots do my bidding for a couple years. The control language was a computer language most similar to Pascal (maybe nobody has heard of that anymore) I went to GM for training and they also had a computer program with robot simulator so you could test your code at your desk. I remember Pascal, and I used it to write a serious suite programs -- but it is not really a good choice for such. It was designed as a teaching language, to make it difficult for you to engage in bad programming habits. But in the process, it makes a lot of things awkward to do. (This was a version of ISO standard Pascal. I think that Borland's turbo Pascal, and UCSD Pascal were a bit more forgiving, but I never used them. Anyway, 20 years ago, I found writing programs for robots to be easier than PLC programs. I wounder how a machine control program which resembles Pascal would be to work with. Enjoy, DoN. -- Some of the German Siemens programmers that program our controls use SCL (Structured Control Language) that is supposed to be like Pascal. Here's an example of their code: IF ActualWeight=CoarseCutOff THEN // Dosieren bis der CutOffCoarse erreicht ist State:=StateFineSpeedDosing; // AbschaltPunkt für das Umschalten von Grob und Feinsdosierung END_IF; ELSE State:=StateIdle; END_IF; GOTO Fine; ; StateFineSpeedDosing: IF Start THEN Takt:=Takt+1; M1_SSP:=FineSpeed; // 0..100% Ansteuerung des Motors M1_OnOff:=True; // Ein/Aus für Motor DSV_OpenClose:=True; // Klappe auf IF (NOT ReleaseCapture) THEN OldActFineWeight:=ActualWeight; // bzw wenn gleich Fine angefangen wird (AbruchRestart muss noch rein) ReleaseCaptu=True; TaktRelease:=1; GOTO Fine; END_IF; ; RogerN |
#13
Posted to rec.crafts.metalworking
|
|||
|
|||
Learning industrial robotics, any favorite robots?
"Karl Townsend" wrote in message
.. . ... Does the welding robot have the controller? I'm wondering about shipping, how far away and any idea on weight? For learning purposes, I'm looking at some little robots on eBay, like they use in schools for robotics training. I'd prefer a more industrial robot but finding something low cost that works nearby is the trick. I could take a college course with robotics but I can learn more by buying a robot and reading the instructions, doing some projects. RogerN Other than moving points, the robot waits for inputs, and fires outputs. Programming is the simple part. My son's robot and controller would weigh maybe 1000 lbs. so shipping would be the main cost. send me your email if you're serious karltownsendATembarqmail.com email sent. RogerN regoratmidwest.net |
#14
Posted to rec.crafts.metalworking
|
|||
|
|||
Learning industrial robotics, any favorite robots?
On 7/26/2013 8:26 PM, Jim Wilkins wrote:
"David R. Birch" wrote in message ... My favorite robot was Rhoda, as played by Julie Newmar on the show "My Living Doll". David She was my favorite Catwoman, too. Eartha Kitt and Halle Berry were also hot as Catwoman. For some reason, I have no memory of Lee Meriwether in the role. David |
#15
Posted to rec.crafts.metalworking
|
|||
|
|||
Learning industrial robotics, any favorite robots?
David R. Birch wrote:
On 7/26/2013 8:26 PM, Jim Wilkins wrote: "David R. Birch" wrote in message ... My favorite robot was Rhoda, as played by Julie Newmar on the show "My Living Doll". David She was my favorite Catwoman, too. Eartha Kitt and Halle Berry were also hot as Catwoman. For some reason, I have no memory of Lee Meriwether in the role. David She was in the '66 Batman movie. Catwoman/Kitka. Julie Newmar was the TV catwoman at the time but had signed on to a different project. -- Steve W. |
#16
Posted to rec.crafts.metalworking
|
|||
|
|||
Learning industrial robotics, any favorite robots?
"passerby" wrote in message
ups.com... replying to RogerN , passerby wrote: regor wrote: So I was thinking about looking for a bargain industrial style robot, something I can use to learn about robotics. Any favorites as far as friendly companies, online documentation, etc.? I don't want to buy a $1500 bargain robot only to find out there is no available documentation or it requires high $$$ software or something. I'd like it to be something with demand like Fanuc or ABB or other major industrial robotics manufacturers. Perhaps start with something that's more geared towards learning? Like this: http://youtu.be/ov0SJJt2PhY Lookup Scorbot (a.k.a. Eshed Robotech, Intelitek, Depco) - you can start with an ER-III which is almost like a toy (but has all the functionality of a "proper" industrial robot) and, if that's not enough, progress to ER-VII (almost industrial - perhaps used somewhere in light industry) and then onto ER-9, an actual industrial robot. There's a ton of info online and there are quite a few on eBay at any given time, all within $300-$400 range, and sometimes have add-ons like conveyors, linear screw stages and rotary tables. Can definitely outfit the whole lab for under $1000 -- posted from http://www.polytechforum.com/metalwo...ts-580710-.htm using PolytechForum's Web, RSS and Social Media Interface to rec.crafts.metalworking and other engineering groups I've been looking at the smaller educational robots, it looks like I could get something functional for less money than the industrial robots, and they are more shipping friendly. Many of the jobs I see where they want you to have robotics experience specify ABB, Fanuc, or whatever brand(s) they use. That's why I'd prefer a brand of robot that is in demand in industry, I know that what I would learn on a Scorbot would apply to other robots but employers don't seem to understand this. If this was applied to cars you'd have to have experience driving every make and model of car or else go to training, knowing how to drive is the key, you can learn the differences as you go. RogerN |
#17
Posted to rec.crafts.metalworking
|
|||
|
|||
Learning industrial robotics, any favorite robots?
"F. George McDuffee" wrote in message
... snip ======================== While we all like to use our own "stuff," you would most likely be far ahead to check if any of the community colleges or vo-techs in your area have a robotics class or two, You can learn on their equipment, the learning is structured, and you are "net working." In most cases you can sign up for single classes with the consent of the instructor, but most likely these will be non-credit [toward degree or certificate]. Also check with your local job placement office as all or part of the tuition/fees/books may be covered. I agree if the schools would go deep enough into the robotics to be useful. My previous robotic experience includes jogging to positions to teach the robot and then the robot follows the path when you run the program. A guy at work said that's all they did with their robotic arm at the technical school. I would like to go a lot deeper, interfacing with PLC's and perhaps machine vision. Educational home projects for robotics might include reloading ammo, changing parts on the CNC mill, maybe it could stir supper and become wife friendly. I can just see her tearing down my automated reloading to "stir constantly while bringing to a boil"! RogerN |
#18
Posted to rec.crafts.metalworking
|
|||
|
|||
Learning industrial robotics, any favorite robots?
I found some simulator programs where you can write programs and test run them. Here's one, free for educational purposes. V-rep pro edu http://www.coppeliarobotics.com/ Others: http://en.wikipedia.org/wiki/Robotics_simulator RogerN |
#19
Posted to rec.crafts.metalworking
|
|||
|
|||
Learning industrial robotics, any favorite robots?
On 2013-07-27, Jim Wilkins wrote:
"DoN. Nichols" wrote in message ... I wounder how a machine control program which resembles Pascal would be to work with. Enjoy, DoN. The semiconductor test stations I worked on used a DEC dialect of Pascal, with a few Assembly hardware drivers. Programming test routines wasn't difficult as long as we paid close attention to variable typing, which meant bits and short integers in that application. We designed the hardware registers to mesh cleanly, like one status bit per byte rather than grouping and masking them. O.K. Made it a bit more tolerable. The Pascal I used (and this was in a database program) would not allow assignment of data between different length string variables -- unless you did it one byte at a time. A real pain, and a bunch of functions specifically for that. But -- it *did* handle random access files, and that plus the RECORD data type made it quite good for the application, other than the string assignment pain. I've written a fair amount of hardware interfacing code in QBasic, which is part way between Pascal and C, with the structure and typing available but not as mandatory, and a single level of pointers that enables reckless variable abuse such as embedding a machine language interrupt routine as a String. O.K. Wasn't QBasic one of the compiled ones for CP/M? My above Pascal programs were on an OS-9 system (the real OS-9, not the much later Mac OS-9 -- the last gasp before they went unix based. :-) I eventually ported that program from Pascal to C (once I got a v7 unix box under a 68000 CPU), and that made some things much easier, but I had to use a combination of bitmapped variables to emulate the SET variable from Pascal -- which I had also used. :-) It was one good way to learn both languages at the application level. I really liked having GOTO for exception handlers so they didn't clutter the main DO Loop structure. I wasn't about to ask the professor for formal permission to do an emergency shutdown. :-) The last step in the test station's troubleshooting procedure gave the software manager's home phone number. He wasn't too happy when National Semiconductor called him at 3AM Eastern time. So the troubleshooting procedure did not quite anticipate everything. :-) I presume that he had given permission for his phone number to be in there? And were there provisions for updating that when the manager went on to another company or another job within this company? Enjoy, DoN. -- Remove oil spill source from e-mail Email: (KV4PH) | Voice (all times): (703) 938-4564 (too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html --- Black Holes are where God is dividing by zero --- |
#20
Posted to rec.crafts.metalworking
|
|||
|
|||
Learning industrial robotics, any favorite robots?
"DoN. Nichols" wrote in message
... On 2013-07-27, Jim Wilkins wrote: O.K. Wasn't QBasic one of the compiled ones for CP/M? My above Pascal programs were on an OS-9 system (the real OS-9, not the much later Mac OS-9 -- the last gasp before they went unix based. :-) The release I was using dated from around 1990, and could execute either interpreted within the editor or compiled to a stand-alone ..EXE, which was very helpful. A similar version was native to DOS 6.22 and it can run (poorly) under NTVDM in Windows. We started with Visual Basic 5 but dropped it because it lacked the INP and OUT instructions that allow low-level hardware I/O access. http://www.softpedia.com/get/Program...s/Qbasic.shtml The goal was to write IC application board programs that would run on customers' unmodified lab PCs, which were typically older office hand-downs. At that time all PCs had LPT ports but few had USB. The LPT port is very simple to use for direct digital input and output. In DOS the serial ports aren't much harder to set up to talk to custom hardware. Windows polls them, destroying your setup. The last step in the test station's troubleshooting procedure gave the software manager's home phone number. He wasn't too happy when National Semiconductor called him at 3AM Eastern time. So the troubleshooting procedure did not quite anticipate everything. :-) I presume that he had given permission for his phone number to be in there? And were there provisions for updating that when the manager went on to another company or another job within this company? He didn't know his number was in there until he received the first late-night phone call. He was extremely sarcastic and deserving of some payback. jsw |
#21
Posted to rec.crafts.metalworking
|
|||
|
|||
Learning industrial robotics, any favorite robots?
On 2013-07-28, Jim Wilkins wrote:
"DoN. Nichols" wrote in message ... On 2013-07-27, Jim Wilkins wrote: O.K. Wasn't QBasic one of the compiled ones for CP/M? My above Pascal programs were on an OS-9 system (the real OS-9, not the much later Mac OS-9 -- the last gasp before they went unix based. :-) The release I was using dated from around 1990, and could execute either interpreted within the editor or compiled to a stand-alone .EXE, which was very helpful. A similar version was native to DOS 6.22 and it can run (poorly) under NTVDM in Windows. O.K. Yes, interpreted makes debugging and experimenting easier, as long as the compiled code behaves the same as the interpreted code. :-) We started with Visual Basic 5 but dropped it because it lacked the INP and OUT instructions that allow low-level hardware I/O access. http://www.softpedia.com/get/Program...s/Qbasic.shtml O.K. Something which Intel processors would support, but not ones like the Motorola 6800, 6809, and the 68000 family, which don't have separate I/O instructions and just use memory mapped I/O devices with standard read and write type instructions. The goal was to write IC application board programs that would run on customers' unmodified lab PCs, which were typically older office hand-downs. At that time all PCs had LPT ports but few had USB. The LPT port is very simple to use for direct digital input and output. In DOS the serial ports aren't much harder to set up to talk to custom hardware. Windows polls them, destroying your setup. Hmm ... no way to tell Windows to keep its hands off those ports? Another reason not to like Windows, then. :-) The last step in the test station's troubleshooting procedure gave the software manager's home phone number. He wasn't too happy when National Semiconductor called him at 3AM Eastern time. So the troubleshooting procedure did not quite anticipate everything. :-) I presume that he had given permission for his phone number to be in there? And were there provisions for updating that when the manager went on to another company or another job within this company? He didn't know his number was in there until he received the first late-night phone call. He was extremely sarcastic and deserving of some payback. Sounds like the team got the payback satisfaction, then. Were the problems in the code a result of some limits which he put on the team, thus making it even more appropriate that he get the o-dark-hundred calls? :-) Enjoy, DoN. -- Remove oil spill source from e-mail Email: | (KV4PH) Voice (all times): (703) 938-4564 (too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html --- Black Holes are where God is dividing by zero --- |
#22
Posted to rec.crafts.metalworking
|
|||
|
|||
Learning industrial robotics, any favorite robots?
"DoN. Nichols" wrote in message
... On 2013-07-28, Jim Wilkins wrote: Windows polls them, destroying your setup. Hmm ... no way to tell Windows to keep its hands off those ports? Another reason not to like Windows, then. :-) Windows periodically checks printer status with the control bits, and has a fit when it sees some combinations of the status bits. AFAIK it leaves the data bits alone. I wrote a program to display and control each bit. Sounds like the team got the payback satisfaction, then. Were the problems in the code a result of some limits which he put on the team, thus making it even more appropriate that he get the o-dark-hundred calls? :-) A state-of-the-art semiconductor test station is a very complex and tricky machine that the IC designers may use in ways they wouldn't reveal to us. Like machine tools some combinations of operations will misbehave or crash. For example to measure the resistivity of certain IC structures you might have to apply 100 Volts and measure the resulting current flow in picoAmps. 100 V in the wrong place can do a bit of harm. The current sensing circuit for that was an AD515 op anp integrator with a 10pF silver-mica feedback cap. Its residual noise level was a few hundred femtoAmps. At those levels the error current from dielectric absorption can appear huge, so we had W.L.Gore make us special Teflon-insulated reed relays for the switching matrix. Even they weren't immune but the absorption current dropped below a picoAmp within 5mS, which was acceptable. http://en.wikipedia.org/wiki/Dielectric_absorption Simply not tightening the shelding enough raised the noise dramatically. Without the shield it was a fine intruder detector. Surprisingly I needed only a space frame box with wide-open sides to fully shield it for the test and calibration fixture. The circuit rejected 60 Hz and above very well and the seemingly gaping access holes were too small for lower frequencies. At a previous job I had designed and built a test station that measured the reverse leakage of TV high voltage rectifier diodes. The circuit forced 1 microAmp at up to 40,000V. The sample diodes measured over 25KV at that microAmp. The current regulator was a 1 MegaWatt (pulse) radar transmitter tube with X-Ray shielding. jsw |
#23
Posted to rec.crafts.metalworking
|
|||
|
|||
Learning industrial robotics, any favorite robots?
"DoN. Nichols" wrote in message
... On 2013-07-28, Jim Wilkins wrote: O.K. Yes, interpreted makes debugging and experimenting easier, as long as the compiled code behaves the same as the interpreted code. :-) Functionally the execution appeared to be identical but of course the timing was very different, so software-generated I2C communications with the Device Under Test only worked properly when compiled. My automatic timing calibration routine had a limited dynamic range that couldn't handle both 2 GHz compiled and 75 MHz interpreted. The target device was an early Power Over Ethernet controller that could do some serious harm if it turned on the 48 VDC when it shouldn't. I was skywiring those 0.5mm-pitch QFPs over the charred crater where the engineer had burned one up. It wasn't as bad as the Hot Swap PCI card controller whose applications board shorted out the power supply on command. Hopefully the IC limited the current well and fast enough to keep mobo voltages stable. That was the most difficult circuit board outline I had to construct, followed closely by the 3-dimensional Segway Balance Sensor Assembly. jsw |
#24
Posted to rec.crafts.metalworking
|
|||
|
|||
Learning industrial robotics, any favorite robots?
Jim Wilkins wrote: "David R. Birch" wrote in message ... My favorite robot was Rhoda, as played by Julie Newmar on the show "My Living Doll". David She was my favorite Catwoman, too. http://www.hulu.com/search?q=my+living+doll -- Anyone wanting to run for any political office in the US should have to have a DD214, and a honorable discharge. |
#25
Posted to rec.crafts.metalworking
|
|||
|
|||
Learning industrial robotics, any favorite robots?
On 2013-07-29, Jim Wilkins wrote:
"DoN. Nichols" wrote in message ... On 2013-07-28, Jim Wilkins wrote: Windows polls them, destroying your setup. Hmm ... no way to tell Windows to keep its hands off those ports? Another reason not to like Windows, then. :-) Windows periodically checks printer status with the control bits, and has a fit when it sees some combinations of the status bits. AFAIK it leaves the data bits alone. I wrote a program to display and control each bit. Can you uninstall the port from within Windows, and just let your program handle it without interference? Sounds like the team got the payback satisfaction, then. Were the problems in the code a result of some limits which he put on the team, thus making it even more appropriate that he get the o-dark-hundred calls? :-) A state-of-the-art semiconductor test station is a very complex and tricky machine that the IC designers may use in ways they wouldn't reveal to us. Like machine tools some combinations of operations will misbehave or crash. :-) For example to measure the resistivity of certain IC structures you might have to apply 100 Volts and measure the resulting current flow in picoAmps. 100 V in the wrong place can do a bit of harm. Understood. Many logic ICs are allergic to more than about 5.5VDC. :-) But can the people using it understand that what they did caused the problem and look for another way to do it instead of calling for support? (Or were they calling to find out what needed replacing after doing that? :-) The current sensing circuit for that was an AD515 op anp integrator with a 10pF silver-mica feedback cap. Its residual noise level was a few hundred femtoAmps. Pretty tiny. At those levels the error current from dielectric absorption can appear huge, so we had W.L.Gore make us special Teflon-insulated reed relays for the switching matrix. Even they weren't immune but the absorption current dropped below a picoAmp within 5mS, which was acceptable. http://en.wikipedia.org/wiki/Dielectric_absorption I remember as a kid playing with components removed from old tube radios, I found that the wound paper-foil capacitors common at that time (early 1950s when I was taking them apart, and figure them to be perhaps 15-20 years old at that time), I could almost always get a click when connecting something as small as 0.01 µf across headphones -- even after leaving them shorted for a few hours. And I remember reading about electrets (form a capacitor by melting the dielectric between electrodes at voltage and letting it solidify while the voltage was applied. This was used to polarize some condenser microphones at one period -- before phantom power became common. Simply not tightening the shelding enough raised the noise dramatically. Without the shield it was a fine intruder detector. :-) Surprisingly I needed only a space frame box with wide-open sides to fully shield it for the test and calibration fixture. The circuit rejected 60 Hz and above very well and the seemingly gaping access holes were too small for lower frequencies. Electrostatic fields only -- not electromagnetic? At a previous job I had designed and built a test station that measured the reverse leakage of TV high voltage rectifier diodes. The circuit forced 1 microAmp at up to 40,000V. The sample diodes measured over 25KV at that microAmp. The current regulator was a 1 MegaWatt (pulse) radar transmitter tube with X-Ray shielding. Hmm ... I remember at Transitron (early 1960s) one item on the production line (long before computer controlled tests) was a reverse voltage leakage test for high voltage diode assemblies. Think about the size of a billy club made of a spiral of diodes potted in black epoxy, and perhaps 12" long with an anode cap (like from a tube) on both ends Current was measured with tube based OP-AMPs (Philbrick IIRC). At the time, an OP-AMP was a black box to me -- no idea how to use it. Now, I love them. And the high voltage was developed by a voltage multipler (perhaps 12-15 stage) using somewhat more reasonable size diode assemblies. The door was set up with a knob which you had to turn through about 40 revolutions to open it up -- and the first few turns opened an interlock switch and lowered a discharging bar into contact -- long before you got enough turns to open the door. The threads were buttress threads engaging spring wires, so you could just shove it closed quickly -- a nod to production efficiency. :-) The only use of computers then and there was a mainframe being used to match forward thermal characteristics of stabistors (diodes selected for their forward voltage characteristics, zener diodes, and the base-emitter forward drop of a transistor -- all checked at -50C, +50C, and +150C in silicone oils. They would test hundreds of each at a time, punch cards for each, and feed them into the computers to select the best match of the three for building "ref-amps" (a starting point for a voltage regulator). The selection process was not perfect -- we got a selected number from a bach back to test from the customer. They were right at the three temperatures, but out of spec between them. :-) Enjoy, DoN. -- Remove oil spill source from e-mail Email: | (KV4PH) Voice (all times): (703) 938-4564 (too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html --- Black Holes are where God is dividing by zero --- |
#26
Posted to rec.crafts.metalworking
|
|||
|
|||
Learning industrial robotics, any favorite robots?
replying to RogerN , passerby wrote:
regor wrote: I've been looking at the smaller educational robots, it looks like I could get something functional for less money than the industrial robots, and they are more shipping friendly. That's just the thing! There's no way you can do much with a Fanuc in a residential home - it's just too darn large, heavy, needs too much power etc. I happen to have a Scorbot ER-VII, which is the smallest you can get that's close to an actual industrial robot, and it's about 70 pounds. I needed a truck with a lift gate to deliver it (palleted with controller and linear stage), paid extra for residential delivery here and still regret I bought it. Since everything you do in training is a simulation of sorts, there's nothing that an ER-V (only about 24 lbs) can't do that ER-VII can. I was lucky to have found an inexpensive ER-V+ for which I could reuse the controller and the linear stage. The ER-VII sits on the floor, a 66lbs boat anchor. I need my son's help to even move it when it gets in the way, a waste of money. So, if you don't have a space with a loading dock and some sturdy benches, 400A service etc., I would not even consider buying anything that's an actual industrial robot. It may even be useful to start with a $150 Armdroid, LabVolt1000 or a similar TeachMover - almost toys but not quite and very easy to handle. In fact, I think that the most useful set in a house would be still a Scorbot but the smallest ER-2U (U stands for USB controller, very important these days). It has all the software of the slightly larger ones, same controller as ER-IV with some extra I/Os and it's small enough to put on the desk, play with it, then put it back on the shelf. ER-2U goes for about $300 with controller included on eBay these days. Many of the jobs I see where they want you to have robotics experience specify ABB, Fanuc, or whatever brand(s) they use. That's why I'd prefer a brand of robot that is in demand in industry, I know that what I would learn on a Scorbot would apply to other robots but employers don't seem to understand this. I have never met an employer who would not want to hire a tech who's ready to go right now, on any equipment they put in front of him. Most of the time they're not ready to pay the wages such person would require, so usually a compromise is found somewhere in between. You have to demonstrate that you are "teachable", and having some experience with small robots might help. (Disclaimer: robots are a hobby for me, I never needed to bring my robotics lab up in an interview. But I do have a lab with the equipment that I do work with professionally and it does help to get the conversation going) -- posted from http://www.polytechforum.com/metalwo...ts-580710-.htm using PolytechForum's Web, RSS and Social Media Interface to rec.crafts.metalworking and other engineering groups |
#27
Posted to rec.crafts.metalworking
|
|||
|
|||
Learning industrial robotics, any favorite robots?
"DoN. Nichols" wrote in message
... On 2013-07-29, Jim Wilkins wrote: Surprisingly I needed only a space frame box with wide-open sides to fully shield it for the test and calibration fixture. The circuit rejected 60 Hz and above very well and the seemingly gaping access holes were too small for lower frequencies. Electrostatic fields only -- not electromagnetic? There was no inductance sensitive to it. We all knew to minimize the physical size of the summing junction node to avoid such parasitics. However the circuit I built to measure the dielectric absorption current decay rate picked up ~40KHz audio from the security sensors. The project manager, a brilliant physicist, calculated that the outer panels were vibrating about a micron to cause the coupling we saw. I cured it by creasing them on a brake. From the mistakes I've seen on commercial products it seems that PC board layout designers who understand electronics are rare. I could do a high-speed digital board with dramatically less noise that the usual products of commercial PC board companies. I debugged one failing example that had 3V of ground bounce between two points on the same plane, because it had been notched into a star configuration that was wrong for the 74AS logic on it. Hmm ... I remember at Transitron (early 1960s) one item on the production line (long before computer controlled tests) was a reverse voltage leakage test for high voltage diode assemblies. Think about the size of a billy club made of a spiral of diodes potted in black epoxy, and perhaps 12" long with an anode cap (like from a tube) on both ends. AFAICT exotica like voltage multipliers, dielectric absorption, magnetic amplifiers and ferroresonant transformers aren't covered well in EE courses, but must be learned through job experience. I picked up a lot of subtleties that new EEs didn't know. One of them insisted that an open collector transistor driven from a gate didn't need a series base resistor because the transistor model he had learned had a current source in the base lead. I couldn't convince him that the base was just a diode to ground. He didn't stay long, the rumor was that he touched a large exposed electrolytic with 480VAC while putzing with the three phase connections to a power supply. I was working on a machine next to it but out sick that day, and came in to find the floor and the side of my machine blackened from the explosion. jsw |
#28
Posted to rec.crafts.metalworking
|
|||
|
|||
Learning industrial robotics, any favorite robots?
On Mon, 29 Jul 2013 06:18:01 +0000, passerby
wrote: replying to RogerN , passerby wrote: regor wrote: I've been looking at the smaller educational robots, it looks like I could get something functional for less money than the industrial robots, and they are more shipping friendly. That's just the thing! There's no way you can do much with a Fanuc in a residential home - it's just too darn large, heavy, needs too much power etc. I happen to have a Scorbot ER-VII, which is the smallest you can get that's close to an actual industrial robot, and it's about 70 pounds. I needed a truck with a lift gate to deliver it (palleted with controller and linear stage), paid extra for residential delivery here and still regret I bought it. Since everything you do in training is a simulation of sorts, there's nothing that an ER-V (only about 24 lbs) can't do that ER-VII can. I was lucky to have found an inexpensive ER-V+ for which I could reuse the controller and the linear stage. The ER-VII sits on the floor, a 66lbs boat anchor. I need my son's help to even move it when it gets in the way, a waste of money. So, if you don't have a space with a loading dock and some sturdy benches, 400A service etc., I would not even consider buying anything that's an actual industrial robot. It may even be useful to start with a $150 Armdroid, LabVolt1000 or a similar TeachMover - almost toys but not quite and very easy to handle. In fact, I think that the most useful set in a house would be still a Scorbot but the smallest ER-2U (U stands for USB controller, very important these days). It has all the software of the slightly larger ones, same controller as ER-IV with some extra I/Os and it's small enough to put on the desk, play with it, then put it back on the shelf. ER-2U goes for about $300 with controller included on eBay these days. Many of the jobs I see where they want you to have robotics experience specify ABB, Fanuc, or whatever brand(s) they use. That's why I'd prefer a brand of robot that is in demand in industry, I know that what I would learn on a Scorbot would apply to other robots but employers don't seem to understand this. I have never met an employer who would not want to hire a tech who's ready to go right now, on any equipment they put in front of him. Most of the time they're not ready to pay the wages such person would require, so usually a compromise is found somewhere in between. You have to demonstrate that you are "teachable", and having some experience with small robots might help. (Disclaimer: robots are a hobby for me, I never needed to bring my robotics lab up in an interview. But I do have a lab with the equipment that I do work with professionally and it does help to get the conversation going) Here's something that just appeared in my inbox that may be useful for Roger, at least for him to know about: =========================================== Yaskawa Motoman Offers STEM Platform for Education and Workforce Development Dayton, OH (July 2013) - Yaskawa Motoman has released a new STEM Robotics Platform for education and workforce development. A general-purpose platform and a welding education cell are available. The new STEM Robotics Platform offers a selection of pre-engineered robotic solutions that meet the requirements of secondary educational programs focused on advanced manufacturing and robotics. The standard configurations and available options provide a package of leading technologies typically encountered in manufacturing environments, including components provided by the Yaskawa Motoman Education Consortium (YMEC). Educators can purchase a complete package or components to build a custom education system that best fits planned course work and classroom layout. "We developed the STEM Robotics Platform to provide community colleges, vocational schools and technical colleges with the best possible equipment for teaching industrial robotics," said Erik Nieves, technology director. "Students are excited about robotics. The success of high school robot competitions like FIRST® and Vex make students enthusiastic about robot programming, and each year, growing numbers are looking for opportunities to learn more." Instructors want course work to be relevant and directly applicable to industry. The best colleges support their local community by preparing students to be successful on Day 1 of their careers as technicians and engineers in factories and other industries. To learn more about Robotics for Education and Workforce Development, visit stem.motoman.com. Additional education tools are offered, including the Simple Education System (SES) and customizable training programs. SES is a PC-based robot simulator that allows customers to learn to operate and program Motoman® robots in the virtual world while keeping their actual robots in production. About Yaskawa Motoman Founded in 1989, the Motomon of Yaskawa Aman Robotics Divisierica, Inc. is a leading robotics company in the Americas. With over 270,000 Motoman® robots installed globally, Yaskawa provides automation products and solutions for virtually every industry and robotic application; including arc welding, assembly, coating, dispensing, material handling, material cutting, material removal, packaging, palletizing and spot welding. For more information please visit our website at www.motoman.com or call 937.847.6200. ============================================ -- Ed Huntress |
#29
Posted to rec.crafts.metalworking
|
|||
|
|||
Learning industrial robotics, any favorite robots?
replying to Ed Huntress , passerby wrote:
huntres23 wrote: On Mon, 29 Jul 2013 06:18:01 +0000, passerby Here's something that just appeared in my inbox that may be useful for Roger, at least for him to know about: =========================================== Yaskawa Motoman Offers STEM Platform for Education and Workforce Development Dayton, OH (July 2013) - Yaskawa Motoman has released a new STEM Robotics Platform for education and workforce development. A general-purpose platform and a welding education cell are available. ... Instructors want course work to be relevant and directly applicable to industry. The best colleges support their local community by preparing students to be successful on Day 1 of their careers as technicians and engineers in factories and other industries. To learn more about Robotics for Education and Workforce Development, visit stem.motoman.com. Thanks for the link, Ed. There is a video demonstration of the 5kg payload version on that page: http://youtu.be/mzazFNdJ5pM What we are looking at is probably a $10,000+ (and I may actually be low-balling it by at least one zero) piece of gear. Good for a university but tough to swallow for an individual. He does mention there's also a smaller 2 kg robot but still... Perhaps it's just been my experience looking for these decommissioned educational robots on eBay but I balked at his phrase "... for a school that is looking to add robotics curriculum ..." - from the looks of it in the last decade all I've seen is them dropping the "robotics curriculum" that was actually established in the late 80s early 90s and by now have noone to actually teach it. -- posted from http://www.polytechforum.com/metalwo...ts-580710-.htm using PolytechForum's Web, RSS and Social Media Interface to rec.crafts.metalworking and other engineering groups |
#30
Posted to rec.crafts.metalworking
|
|||
|
|||
Learning industrial robotics, any favorite robots?
On 2013-07-29, Jim Wilkins wrote:
"DoN. Nichols" wrote in message ... On 2013-07-29, Jim Wilkins wrote: Surprisingly I needed only a space frame box with wide-open sides to fully shield it for the test and calibration fixture. The circuit rejected 60 Hz and above very well and the seemingly gaping access holes were too small for lower frequencies. Electrostatic fields only -- not electromagnetic? There was no inductance sensitive to it. We all knew to minimize the physical size of the summing junction node to avoid such parasitics. O.K. However the circuit I built to measure the dielectric absorption current decay rate picked up ~40KHz audio from the security sensors. The project manager, a brilliant physicist, calculated that the outer panels were vibrating about a micron to cause the coupling we saw. I cured it by creasing them on a brake. Simple cure -- if you know to apply it. From the mistakes I've seen on commercial products it seems that PC board layout designers who understand electronics are rare. I could do a high-speed digital board with dramatically less noise that the usual products of commercial PC board companies. I debugged one failing example that had 3V of ground bounce between two points on the same plane, because it had been notched into a star configuration that was wrong for the 74AS logic on it. :-) Hmm ... I remember at Transitron (early 1960s) one item on the production line (long before computer controlled tests) was a reverse voltage leakage test for high voltage diode assemblies. Think about the size of a billy club made of a spiral of diodes potted in black epoxy, and perhaps 12" long with an anode cap (like from a tube) on both ends. AFAICT exotica like voltage multipliers, dielectric absorption, magnetic amplifiers and ferroresonant transformers aren't covered well in EE courses, but must be learned through job experience. While working for Night Vision Labs (US Army lab) I got lots of experience with multipliers. Little oscillators run from mercury cells (now unobtainum) produced about 1 KV P-P, and went through a large number of stages to produce up to 15 KV for the small ones, and 45 KV for the large ones -- to run cascaded image intensifier tubes. All potted in about a 120 degree segment of a thick-walled cylinder with taps out one long edge to feed the voltages to the intensifiers. Then add the high-voltage pulse generators intended to turn the intensifiers on and off to allow selecting distance with a pulsed NdYAG laser as an illuminator. :-) I picked up a lot of subtleties that new EEs didn't know. One of them insisted that an open collector transistor driven from a gate didn't need a series base resistor because the transistor model he had learned had a current source in the base lead. I couldn't convince him that the base was just a diode to ground. Ouch! All models and no real life experience. How many did he fry? :-) Even a SPICE model of the circuit should tell him how wrong he was, if he bothered to read the currents -- even though the SPICE models for transistors don't bother to model cooked junctions or vaporized bonding wires. :-) He didn't stay long, the rumor was that he touched a large exposed electrolytic with 480VAC while putzing with the three phase connections to a power supply. I was working on a machine next to it but out sick that day, and came in to find the floor and the side of my machine blackened from the explosion. Ouch! Good day to be out sick or otherwise out of range. Touched it with *what*? Something metal to vaporize -- or was the black from carbonized employee? Reminds me of a story from a friend who worked for AT&T Long Lines. One new employee was given the job of opening each of the knife switches (while power was being supplied from the other battery bank) and greasing the mating surfaces, and then re-engaging them. He was not very strong (at least not strong enough), and those knife switches had a *lot* of grip, so he got a crowbar, and used it to pry open the switches by the insulating crossbar which joined the switches for both sides of the battery (and the handle, of course). Only -- when the switch let go, he slipped, and one end touched the hot side fo the switch, and the other end hit the metal doors on the racks behind him. Well ... given the size of the battery banks, it did not take long at all for it to slice through the door, spraying molten steel all around. When he got out of the hospital, he was allowed to do nothing but push a broom until he got the idea and quit. We never worked with *that* much power -- most things were man portable -- but we did have a 28V lead-acid storage battery for testing a DC-powered laser pump, and one of the other employees came back into the room carrying it and commenting on how good a battery it was. He had taken it out to start his car because the battery had died from the cold and age. He was impressed with how fast it cranked the engine. (I asked him if he had turned on any lights while it was connected, and if so, he should check to see whether they were burned out. he had not noticed the twelve filler caps on it instead of the usual six -- or did not realize the significance. At least this was before computers in control of the car's electronics. :-) Enjoy, DoN. -- Remove oil spill source from e-mail Email: | (KV4PH) Voice (all times): (703) 938-4564 (too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html --- Black Holes are where God is dividing by zero --- |
#31
Posted to rec.crafts.metalworking
|
|||
|
|||
Learning industrial robotics, any favorite robots?
"passerby" wrote in message
ups.com... replying to RogerN , passerby wrote: snip I have never met an employer who would not want to hire a tech who's ready to go right now, on any equipment they put in front of him. Most of the time they're not ready to pay the wages such person would require, so usually a compromise is found somewhere in between. You have to demonstrate that you are "teachable", and having some experience with small robots might help. (Disclaimer: robots are a hobby for me, I never needed to bring my robotics lab up in an interview. But I do have a lab with the equipment that I do work with professionally and it does help to get the conversation going) -- posted from http://www.polytechforum.com/metalwo...ts-580710-.htm A Scorbot III with controller came up on eBay with a reasonable "Buy it now" so I bought it. The robot should be on the way soon, I have a tracking number but no tracking information yet. I tried out the software in a laptop with Windows XP, it seems to run fine. I found a serial port monitor program that lets me know the communications on the serial port so I hope to reverse engineer the PC commands to the controller. My idea is to be able to write programs and run them on the PC, the PC would then send move commands to the Scorbot, read I/O, etc. So the program would actually be running in the PC, allowing for very large programs, image processing, and so forth. If this works out, I can try to find information on ABB and Fanuc programming and write a program to execute files written for different makes of robots. I should be able to do get it to work with G-Code too, at least the basic moves, G00, 01, 02, 03. I have seen some Scorbot 4pc's for sale on eBay but so far none come with the ISA controller card. I don't know the detail about the drive yet but it might be compatible with some of the hardware available for LinuxCNC. I saw other brands of educational robot arms on eBay but so far I have been able to find the most information on the Scorbot's. I like the Amatrol Pegasus, roller chain drive looks heavy duty, but from what I hear, Amatrol isn't very helpful to hobbyists. RogerN |
#32
Posted to rec.crafts.metalworking
|
|||
|
|||
Learning industrial robotics, any favorite robots?
replying to RogerN , passerby wrote:
regor wrote: A Scorbot III with controller came up on eBay with a reasonable "Buy it now" so I bought it. Welcome to the wonderful world of Scorbotics! Be sure to sign up for http://tech.groups.yahoo.com/group/ScorbotUserGroup/ if you haven't already. Some manuals and old DOS software are here http://elabz.com/resources/robotics-resources/ I also tried using FreeDOS instead of XP - works like a champ on FreeDOS so no need to use MS, especially if you have LinuxCNC in sights. http://www.freedos.org/ The robot should be on the way soon, I have a tracking number but no tracking information yet. I tried out the software in a laptop with Windows XP, it seems to run fine. When it comes, calibrate it first. ERIII are the oldest (late 80s - early 90s) and most of the time come with cams out of whack. Petals of the optical encoders are often broken, too. I have a few spares in case you need it. I found a serial port monitor program that lets me know the communications on the serial port so I hope to reverse engineer the PC commands to the controller. There is really no need to reverse engineer anything with an ERIII. The box received commands in text mode right through that serial. All the commands are described in the manual, at least in the 6th edition I've got from elabz.com, it's all there. If you really wanted to ditch Scorbase software, you'll just have to make sure that yours produces the same commands and sends over serial. My idea is to be able to write programs and run them on the PC, the PC would then send move commands to the Scorbot, read I/O, etc. So the program would actually be running in the PC, allowing for very large programs, image processing, and so forth. If this works out, I can try to find information on ABB and Fanuc programming and write a program to execute files written for different makes of robots. I should be able to do get it to work with G-Code too, at least the basic moves, G00, 01, 02, 03. ERIII uses DC servo motors with two channel quadrature output encoders with three interrupter petals, so it's only 12TPR (on a 65.5:1 gearbox, and two of the motors on 128:1 if memory serves). It's not a speedy robot, in theory you can even feed that signal right back to LinuxCNC via Parallel port (you will have to provide H-Bridge and PWM for speed control). I've been meaning to mess with that for years now, always putting off for one reason or another ... I have seen some Scorbot 4pc's for sale on eBay but so far none come with the ISA controller card. I don't know the detail about the drive yet but it might be compatible with some of the hardware available for LinuxCNC. I saw other brands of educational robot arms on eBay but so far I have been able to find the most information on the Scorbot's. Don't get ER4PC robot unless you can also find an ER4U Scorpower (the control box has it's own name) and ditch the PC Scorpower. The robot itself is exactly the same, will work with USB control box. The PC servo card that PC version needs is a real PITA. Intelitek still sells it for $600 (and I believe it's refurbished) but it requires a computer with full length AT ISA bus - I haven't seen a monster like this in 15 years, will be a whole project in and of itself just to find a PC to stick it into. I like the Amatrol Pegasus, roller chain drive looks heavy duty, but from what I hear, Amatrol isn't very helpful to hobbyists. I love Pegasus too, maybe will get one at some point. The control principals of almost all of the educational robots of this size designed in the golden era of educational robotics (mid 80s through mid 90s) - Scorbot, LabVolt2000, Mentor, Pegasus, Rhino, etc. - are the same - geared DC motors with optical encoders, so it it possible to have them all work (or at least make them move) despite the fact that people usually throw controller boxes away. They resemble old dilapidated PCs too much... Anyway, thanks for forcing my trip down the memory lane, good luck with your ERIII. Post here or in the robotics groups (here or Yahoo) if you need help. -- posted from http://www.polytechforum.com/metalwo...ts-580710-.htm using PolytechForum's Web, RSS and Social Media Interface to rec.crafts.metalworking and other engineering groups |
#33
Posted to rec.crafts.metalworking
|
|||
|
|||
Learning industrial robotics, any favorite robots?
"passerby" wrote in message
roups.com... replying to RogerN , passerby wrote: regor wrote: snip to find the most information on the Scorbot's. Don't get ER4PC robot unless you can also find an ER4U Scorpower (the control box has it's own name) and ditch the PC Scorpower. The robot itself is exactly the same, will work with USB control box. The PC servo card that PC version needs is a real PITA. Intelitek still sells it for $600 (and I believe it's refurbished) but it requires a computer with full length AT ISA bus - I haven't seen a monster like this in 15 years, will be a whole project in and of itself just to find a PC to stick it into. snip I was thinking of using the 4pc controller as an amplifier box and using LinuxCNC as the controller to provide PWM to the 4pc controller. I have used the Mesa anything I/O boards with LinuxCNC and it has encoder inputs and PWM outputs. I don't know if the 4PC control takes pwm plus direction or exactly what. I thought I could get the Mesa board to replace the PC board for the ER4PC controller, I found the 62 pin high density Sub-D connectors at Digi-Key. Thanks for the info and links, I'll see if I can send ascii commands through RS-232 to the controller. RogerN -- posted from http://www.polytechforum.com/metalwo...ts-580710-.htm using PolytechForum's Web, RSS and Social Media Interface to rec.crafts.metalworking and other engineering groups |
#34
Posted to rec.crafts.metalworking
|
|||
|
|||
Learning industrial robotics, any favorite robots?
replying to RogerN , passerby wrote:
regor wrote: snip I was thinking of using the 4pc controller as an amplifier box and using LinuxCNC as the controller to provide PWM to the 4pc controller. That 4PC controller is essentially a glorified power supply that simply passes the signals from encoders over to the PC Servo card and receives PWM for each motor back. There is also a serial line to the teach pendant that sort of simply passes through. 4U controller looks the same but the brains have been moved from the PC Servo card into the controller, so it's an actual controller together with a power supply, in one box. I have used the Mesa anything I/O boards with LinuxCNC and it has encoder inputs and PWM outputs. I don't know if the 4PC control takes pwm plus direction or exactly what. I thought I could get the Mesa board to replace the PC board for the ER4PC controller, I found the 62 pin high density Sub-D connectors at Digi-Key. I have some kind of unverified pinout for that 62-pin cable from a USC Wiki page for the university's robotics lab that now requires a user name for some reason. I'd be happy to share although it looks suspicious because I cannot find directions (or polarities) identified anywhere and motor control lines are called "Axis 1 Speed" (PWM?) - only one pin per motor. How would it know direction then is a question. Almost all of the other lines are taken by the encoders (there's 6 on the robot itself and 2 more for external axes like linear stage and pickup rotary table) or not connected (or marked as +5V which is also suspect, you would think they'd be grounded instead). -- posted from http://www.polytechforum.com/metalwo...ts-580710-.htm using PolytechForum's Web, RSS and Social Media Interface to rec.crafts.metalworking and other engineering groups |
#35
Posted to rec.crafts.metalworking
|
|||
|
|||
Learning industrial robotics, any favorite robots?
"DoN. Nichols" wrote in message
... On 2013-07-29, Jim Wilkins wrote: He didn't stay long, the rumor was that he touched a large exposed electrolytic with 480VAC while putzing with the three phase connections to a power supply. I was working on a machine next to it but out sick that day, and came in to find the floor and the side of my machine blackened from the explosion. Ouch! Good day to be out sick or otherwise out of range. Touched it with *what*? Something metal to vaporize -- or was the black from carbonized employee? The story I heard was that he and another newbie engineer were attempting to find the proper phase rotation by touching the live 480V cables to the input terminals while squatting on the floor, and one lost his balance. I don't remember who said that or may have seen it happen. Luckily it wasn't me, though I probably would have found a reason to be on the far side of my machine or taken a break. Another time a tech was checking a faulty SCR trigger circuit on the machine beside mine, grounded the scope probe to the SCR cathode and turned on power. The probe cable exploded in midair before the breaker could trip. Fortunately I wasn't injured and his weren't serious. jsw |
#36
Posted to rec.crafts.metalworking
|
|||
|
|||
Learning industrial robotics, any favorite robots?
On 2013-07-30, Jim Wilkins wrote:
"DoN. Nichols" wrote in message ... On 2013-07-29, Jim Wilkins wrote: He didn't stay long, the rumor was that he touched a large exposed [ ... ] my machine blackened from the explosion. Ouch! Good day to be out sick or otherwise out of range. Touched it with *what*? Something metal to vaporize -- or was the black from carbonized employee? The story I heard was that he and another newbie engineer were attempting to find the proper phase rotation by touching the live 480V cables to the input terminals while squatting on the floor, and one lost his balance. Ouch! Really asking for trouble. I don't remember who said that or may have seen it happen. Luckily it wasn't me, though I probably would have found a reason to be on the far side of my machine or taken a break. Another time a tech was checking a faulty SCR trigger circuit on the machine beside mine, grounded the scope probe to the SCR cathode and turned on power. The probe cable exploded in midair before the breaker could trip. Fortunately I wasn't injured and his weren't serious. An argument for a differential plugin for the 'scope -- and the intelligence to know that it was needed. :-) Enjoy, DoN. -- Remove oil spill source from e-mail Email: | (KV4PH) Voice (all times): (703) 938-4564 (too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html --- Black Holes are where God is dividing by zero --- |
Reply |
Thread Tools | Search this Thread |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Forum | |||
US Robotics 28.8 Sportster | Electronic Schematics | |||
33 robots | Metalworking | |||
Japan Robotics Problem | Metalworking | |||
robots | Woodworking | |||
SF Bay Area Combat Robotics Building Course | Metalworking |