For this year Science olympiad, we have to build a robot that picks
stuff and places it into a jar. It has to reach about 5 feet and lift
objects up to 2-3 ounces.

I plan on making it fully automated, unlike last year one that won
the Illinois State Olympiad.

I want to make it's arms to be as lightweight as possible, from some
super thin material. But it has to be easy to work with. Something
like thin aluminum extruded square tubing or some such. Any
suggestions?

Again the arms only need to reach 5 ft and lift 2-3 ounces.

Thanks

i

On Sat, 24 Oct 2015 22:39:37 -0500, Ignoramus23308
wrote:

For this year Science olympiad, we have to build a robot that picks
stuff and places it into a jar. It has to reach about 5 feet and lift
objects up to 2-3 ounces.

I plan on making it fully automated, unlike last year one that won
the Illinois State Olympiad.

I want to make it's arms to be as lightweight as possible, from some
super thin material. But it has to be easy to work with. Something
like thin aluminum extruded square tubing or some such. Any
suggestions?

Again the arms only need to reach 5 ft and lift 2-3 ounces.

Thanks

i
Carbon fiber.

"Ignoramus23308" wrote in message
...

For this year Science olympiad, we have to build a robot that picks
stuff and places it into a jar. It has to reach about 5 feet and lift
objects up to 2-3 ounces.

I plan on making it fully automated, unlike last year one that won
the Illinois State Olympiad.

I want to make it's arms to be as lightweight as possible, from some
super thin material. But it has to be easy to work with. Something
like thin aluminum extruded square tubing or some such. Any
suggestions?

Again the arms only need to reach 5 ft and lift 2-3 ounces.

Thanks

i
================================================== =============

In terms of greatest stiffness per weight of material, round tube is better
than square. I'd start with very thin wall aluminum tubing like you
suggested, in a truss structure. Something like three tubes in a triangle,
connected by smaller short sections angled at 45 degrees to the main tubes
to form a stiff triangulated structure. Something like an antenna mast.

-----
Regards,
Carl Ijames

On Saturday, October 24, 2015 at 8:39:40 PM UTC-7, Ignoramus23308 wrote:
For this year Science olympiad, we have to build a robot ...
I want to make it's arms to be as lightweight as possible, from some
super thin material.

Well, wood iis good, maybe fiberglass tube is better (try Grainger.com, and other
industrial suppliers). Joining by glue is most rigid, and works well
on glue or fiberglass-reinforced-plastic, not so well on aluminum

If money were no object, titanium boiler tubing is a standard stock item... it's light.

On Sat, 24 Oct 2015 22:39:37 -0500, Ignoramus23308
wrote:

For this year Science olympiad, we have to build a robot that picks
stuff and places it into a jar. It has to reach about 5 feet and lift
objects up to 2-3 ounces.

I plan on making it fully automated, unlike last year one that won
the Illinois State Olympiad.

I want to make it's arms to be as lightweight as possible, from some
super thin material. But it has to be easy to work with. Something
like thin aluminum extruded square tubing or some such. Any
suggestions?

Again the arms only need to reach 5 ft and lift 2-3 ounces.

Thanks

i

Fiberglass fish pole sections?
--
cheers,

John B.

On Sat, 24 Oct 2015 22:39:37 -0500, Ignoramus23308
wrote:

For this year Science olympiad, we have to build a robot that picks
stuff and places it into a jar. It has to reach about 5 feet and lift
objects up to 2-3 ounces.

I plan on making it fully automated, unlike last year one that won
the Illinois State Olympiad.

I want to make it's arms to be as lightweight as possible, from some
super thin material. But it has to be easy to work with. Something
like thin aluminum extruded square tubing or some such. Any
suggestions?

Again the arms only need to reach 5 ft and lift 2-3 ounces.

Thanks

i

Carbon-fiber tubes are the high-end solution. There aren't many
materials that are lighter and even fewer that are stiffer, which
probably will be an issue in your design.

It comes in all kinds of grades. You don't need the fancy or expensive
ones. Try Googling "carbon fiber tube" and you'll see what's
available.

Practically all of it is epoxy-resin-based, or compatible with epoxy,
so assembling pieces with it won't be difficult.

--
Ed Huntress

"Ignoramus23308" wrote in
message ...
For this year Science olympiad, we have to build a robot that picks
stuff and places it into a jar. It has to reach about 5 feet and
lift
objects up to 2-3 ounces.

I plan on making it fully automated, unlike last year one that won
the Illinois State Olympiad.

I want to make it's arms to be as lightweight as possible, from some
super thin material. But it has to be easy to work with. Something
like thin aluminum extruded square tubing or some such. Any
suggestions?

Again the arms only need to reach 5 ft and lift 2-3 ounces.

Thanks

i

http://warmlite.com/warmlite-two-person-tent/

http://warmlite.com/tents/tents-technical/

The front pole of my 1970's 2R is ~16mm (5/8") in diameter with a wall
thickness of 0.4mm and weighs 65g per meter including the elastic
cord. The rear pole is 10mm. Jack Stephenson showed me that I could
stand on the middle of a slightly short (~1') scrap section of front
pole supported at the ends by 2x4 blocks.

IIRC it's alloy 7005. This is the current pole material:
http://www.makeitfrom.com/material-p...8-T6-Aluminum/

-jsw

"Ignoramus23308" wrote in
message ...
For this year Science olympiad, we have to build a robot that picks
stuff and places it into a jar. It has to reach about 5 feet and
lift
objects up to 2-3 ounces.

I plan on making it fully automated, unlike last year one that won
the Illinois State Olympiad.

I want to make it's arms to be as lightweight as possible, from some
super thin material. But it has to be easy to work with. Something
like thin aluminum extruded square tubing or some such. Any
suggestions?

Again the arms only need to reach 5 ft and lift 2-3 ounces.

Thanks

i

Maybe you could buy one piece of long enough arrow shaft tubing from a
custom arrow maker, then brace it with struts and stays like a
sailboat mast. You might need a box or drainpipe to protect it in
transport.

-jsw

On Sat, 24 Oct 2015 22:39:37 -0500, Ignoramus23308
wrote:

For this year Science olympiad, we have to build a robot that picks
stuff and places it into a jar. It has to reach about 5 feet and lift
objects up to 2-3 ounces.

I plan on making it fully automated, unlike last year one that won
the Illinois State Olympiad.

"I"? Be careful that you don't get too involved and get your son
disqualified.

Full automation is a very lofty goal, it would seem. How will you
train it to find the object, then place it in a row with others it has
picked up? University teams are still having trouble with this.
G'luck!


I want to make it's arms to be as lightweight as possible, from some
super thin material. But it has to be easy to work with. Something
like thin aluminum extruded square tubing or some such. Any
suggestions?

Are you thinking "enclosed robotic arm" or "automated crane" here?
Hook end or fingers which clamp the object? Where are the rules?
https://www.soinc.org/robot_arm_c Thain't much here.


Again the arms only need to reach 5 ft and lift 2-3 ounces.

Long distance, light weight. For crane style, how about an aluminum
I-beam for the arm? (best pic I could find)
http://www.jneaircraft.com/wp-conten...olesedited.jpg
Rotate the tower, run the arm back and forth on the tower for distance
and have a triangulated pivot point

=====000=======0000==========================?
0 ||
\ ||
\ ||
\ ||
\ ||
0||

-
To change one's self is sufficient. It's the idiots who want
to change the world who are causing all the trouble.
--Anonymous

On Saturday, October 24, 2015 at 11:39:40 PM UTC-4, Ignoramus23308 wrote:
For this year Science olympiad, we have to build a robot that picks
stuff and places it into a jar. It has to reach about 5 feet and lift
objects up to 2-3 ounces.


Thanks

i

I looked at some sites and found http://fiberglasssupply.com/

They have several types of fiber glass as well as kevlar and carbon fiber.

But my advice is to discuss this with your son. You can give him some idea of how to come up with the best material and design. Lots to consider. Cost, ease of working, etc. You might also consider a piece that is tapered. The stress will not be the same close to the robot and at the end doing the pickup. Could also be prestressed with some kevlar or Spectra doing the prestresing.

Dan

On Sat, 24 Oct 2015 22:39:37 -0500, Ignoramus23308 wrote:

For this year Science olympiad, we have to build a robot that picks
stuff and places it into a jar. It has to reach about 5 feet and lift
objects up to 2-3 ounces.

I plan on making it fully automated, unlike last year one that won the
Illinois State Olympiad.

I want to make it's arms to be as lightweight as possible, from some
super thin material. But it has to be easy to work with. Something like
thin aluminum extruded square tubing or some such. Any suggestions?

Again the arms only need to reach 5 ft and lift 2-3 ounces.

Thanks

i

Google "kite" "carbon fiber" "tube". You'll get lots of results.

If you get the extruded tube remember that it tends to split -- I'd
connect to it with ferrules or other things that fully surround it, or
back up the longitudinal fibers with a layer of roving wound crossways.

Lots of stiffness for the weight...

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

On Sun, 25 Oct 2015 08:46:10 -0400, "Jim Wilkins"
wrote:

"Ignoramus23308" wrote in
message ...
For this year Science olympiad, we have to build a robot that picks
stuff and places it into a jar. It has to reach about 5 feet and
lift
objects up to 2-3 ounces.

I plan on making it fully automated, unlike last year one that won
the Illinois State Olympiad.

I want to make it's arms to be as lightweight as possible, from some
super thin material. But it has to be easy to work with. Something
like thin aluminum extruded square tubing or some such. Any
suggestions?

Again the arms only need to reach 5 ft and lift 2-3 ounces.

Thanks

i

http://warmlite.com/warmlite-two-person-tent/

You spend $500 on a wee tent? Wow!


http://warmlite.com/tents/tents-technical/

The front pole of my 1970's 2R is ~16mm (5/8") in diameter with a wall
thickness of 0.4mm and weighs 65g per meter including the elastic
cord. The rear pole is 10mm. Jack Stephenson showed me that I could
stand on the middle of a slightly short (~1') scrap section of front
pole supported at the ends by 2x4 blocks.

IIRC it's alloy 7005. This is the current pole material:
http://www.makeitfrom.com/material-p...8-T6-Aluminum/

Strong stuff, Maynard.

-
To change one's self is sufficient. It's the idiots who want
to change the world who are causing all the trouble.
--Anonymous

On 2015-10-25, Ignoramus23308 wrote:
For this year Science olympiad, we have to build a robot that picks
stuff and places it into a jar. It has to reach about 5 feet and lift
objects up to 2-3 ounces.

[ ... ]

I want to make it's arms to be as lightweight as possible, from some
super thin material. But it has to be easy to work with. Something
like thin aluminum extruded square tubing or some such. Any
suggestions?

Hmm ... one possible source if round would do is from "Texas
Towers" -- telescoping aluminum tubing, 1/16" wall thickness in 1/8"
diameter size steps. Each tube is 6' long. I used some of their
product in making an antenna recently. Not sure whether this will be
light-weight enough for you. They're on the web, so you can see what
they have.

Good Luck,
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 ---

"Ignoramus23308" wrote in message
...
For this year Science olympiad, we have to build a robot that picks
stuff and places it into a jar. It has to reach about 5 feet and lift
objects up to 2-3 ounces.

I plan on making it fully automated, unlike last year one that won
the Illinois State Olympiad.

I want to make it's arms to be as lightweight as possible, from some
super thin material. But it has to be easy to work with. Something
like thin aluminum extruded square tubing or some such. Any
suggestions?

Again the arms only need to reach 5 ft and lift 2-3 ounces.

Thanks

i

Carbone fiber tube. 7075 aluminum for mounting and reinforcing stress
points.

On 25/10/2015 11:39 AM, Ignoramus23308 wrote:
For this year Science olympiad, we have to build a robot that picks
stuff and places it into a jar. It has to reach about 5 feet and lift
objects up to 2-3 ounces.

I plan on making it fully automated, unlike last year one that won
the Illinois State Olympiad.

I want to make it's arms to be as lightweight as possible, from some
super thin material. But it has to be easy to work with. Something
like thin aluminum extruded square tubing or some such. Any
suggestions?

Again the arms only need to reach 5 ft and lift 2-3 ounces.

Thanks

i



Carbon fiber tube from hobby shop. Epoxies well.

Don't demonstrate boastfully how strong it is to your kids - don't ask
how I know this..

On Sat, 24 Oct 2015 22:39:37 -0500, Ignoramus23308 wrote:
For this year Science olympiad, we have to build a robot that picks
stuff and places it into a jar. It has to reach about 5 feet and lift
objects up to 2-3 ounces.
....
I want to make its arms to be as lightweight as possible, from some
super thin material. But it has to be easy to work with. Something
like thin aluminum extruded square tubing or some such. Any
suggestions?

Again the arms only need to reach 5 ft and lift 2-3 ounces.

"Arms as lightweight as possible" might be the wrong focus; I imagine
what you actually want is fast and accurate positioning. A central
tower can be heavy and still have a low moment of inertia as it
rotates with a lightweight boom supported by Kevlar strands. (The tower
could be fixed in place instead of rotating, but that might complicate
things.) A pickup unit would slide back and forth on the boom. Have a
motor and pulley at the tower; another pulley at the end of the boom;
and a loop of Kevlar around the pulleys to drag the slider back and forth.

--
jiw

Gunner, I just received four 10mm square carbon fiber tubes (with a
round hole inside).

They are clearly stronger than steel by far, and so much lighter.

Really amazing material.

Liebherr is now experimenting with carbon fiber as material to make
crane booms. That would greatly increase lifting capacity of cranes
because it would eliminate a lot of weight placed at great radius.

i

On Wednesday, October 28, 2015 at 5:07:53 PM UTC-4, Ignoramus13886 wrote:
Gunner, I just received four 10mm square carbon fiber tubes (with a
round hole inside).


Should be no problem for you. But in long term usages it is important to insulate electrically between the carbon fiber and metals. Carbon is at the very end of the electrochemical series.

Dan

On Wed, 28 Oct 2015 16:07:50 -0500, Ignoramus13886
wrote:

Gunner, I just received four 10mm square carbon fiber tubes (with a
round hole inside).

They are clearly stronger than steel by far, and so much lighter.

Really amazing material.

Liebherr is now experimenting with carbon fiber as material to make
crane booms. That would greatly increase lifting capacity of cranes
because it would eliminate a lot of weight placed at great radius.

i

Its truely some fascinating stuff and strong like you wouldnt believe.
However..when it fails..it seldom bends before failure..it simply
crumples and often unexpectedly depending on design and overload. So
keep it under the load limit and have fun!!