Sorry about the OT, but, you guys know everything.

I'm new to RV'ing and bought a new 5th wheel. Put in new brake linings (two
axles, 4 wheels) and bought a brake controller (Tekonsha Voyager) for my
2000 Chev Silverado truck (truck came with the tow package).

I think I have finally optimized the settings on the brake controller but
still has problems. Upon braking, the 5th wheel electric brakes grab
smoothly and decelerate both vehicles very nicely. However, prior to coming
to a complete stop, as soon as I slightly let up on the brake pedal (say, to
coast a few more feet) the 5th wheel brakes completely release thereby
giving my truck a nice kick in the butt. As I approach the stopped vehicle
in front of me (by now I am down to, say, 1 mph) I am forced to apply the
brakes again, and this process repeats over and over. Very uncomfortable
for me and SWMBO.

IN OTHER WORDS it seems that with electric brakes the deceleration is quite
smooth, but, when you EASE your foot off the brake pedal, the electric
brakes release instantly instead of easing off like conventional brakes.

Can this be adjusted any further? Is this the nature of the beast? Would a
more expensive brake controller actually vary the voltage to the trailer
wheels, or is it a simple "either on or off" issue.

All advice appreciated.

Ivan Vegvary

"Ivan Vegvary" wrote in news:2iCek.162$av4.7@trnddc04:

Can this be adjusted any further? Is this the nature of the beast?
Would a more expensive brake controller actually vary the voltage to
the trailer wheels, or is it a simple "either on or off" issue.

The type of brake controller that you have is pendulum-based and depends
upon its sensing of decelleration of the truck to initiate braking of the
trailer.

You'd be a lot better off with either a Jordan (if they're still in
business) or a BrakeSmart. (I have a Jordan and my Montana never "pushes"
my truck. grin)

"Ivan Vegvary" wrote in message
news:2iCek.162$av4.7@trnddc04...
Sorry about the OT, but, you guys know everything.

I'm new to RV'ing and bought a new 5th wheel. Put in new brake linings
(two axles, 4 wheels) and bought a brake controller (Tekonsha Voyager) for
my 2000 Chev Silverado truck (truck came with the tow package).

I think I have finally optimized the settings on the brake controller but
still has problems. Upon braking, the 5th wheel electric brakes grab
smoothly and decelerate both vehicles very nicely. However, prior to
coming to a complete stop, as soon as I slightly let up on the brake pedal
(say, to coast a few more feet) the 5th wheel brakes completely release
thereby giving my truck a nice kick in the butt. As I approach the
stopped vehicle in front of me (by now I am down to, say, 1 mph) I am
forced to apply the brakes again, and this process repeats over and over.
Very uncomfortable for me and SWMBO.

IN OTHER WORDS it seems that with electric brakes the deceleration is
quite smooth, but, when you EASE your foot off the brake pedal, the
electric brakes release instantly instead of easing off like conventional
brakes.

Can this be adjusted any further? Is this the nature of the beast? Would
a more expensive brake controller actually vary the voltage to the trailer
wheels, or is it a simple "either on or off" issue.

All advice appreciated.

Ivan Vegvary


I think that your truck's brake switch is out of adjustment. When you are
just "easing" into the brakes, check and see if the brake lights are on.
IIRC, that controller will not apply brakes without an input from the pedal
switch. Make sure the pendulum is adjusted properly (straight up and down).
It sounds like you have the gain set properly.

Shawn

Ivan Vegvary wrote:
Sorry about the OT, but, you guys know everything.

I'm new to RV'ing and bought a new 5th wheel. Put in new brake linings (two
axles, 4 wheels) and bought a brake controller (Tekonsha Voyager) for my
2000 Chev Silverado truck (truck came with the tow package).

I think I have finally optimized the settings on the brake controller but
still has problems. Upon braking, the 5th wheel electric brakes grab
smoothly and decelerate both vehicles very nicely. However, prior to coming
to a complete stop, as soon as I slightly let up on the brake pedal (say, to
coast a few more feet) the 5th wheel brakes completely release thereby
giving my truck a nice kick in the butt. As I approach the stopped vehicle
in front of me (by now I am down to, say, 1 mph) I am forced to apply the
brakes again, and this process repeats over and over. Very uncomfortable
for me and SWMBO.

IN OTHER WORDS it seems that with electric brakes the deceleration is quite
smooth, but, when you EASE your foot off the brake pedal, the electric
brakes release instantly instead of easing off like conventional brakes.

Can this be adjusted any further? Is this the nature of the beast? Would a
more expensive brake controller actually vary the voltage to the trailer
wheels, or is it a simple "either on or off" issue.

All advice appreciated.

Ivan Vegvary


My truck/trailer behaves the same, and it does _not_ have a pendulum
type controller.

Electric brakes are aggressively regenerative -- there's an
electromagnet on a puck that works on the inside face of the drum (kinda
like a disk brake), on a long lever arm that actuates the 'real' brakes.
The electromagnet's attraction is inversely proportional to distance
squared, so once it's sticking to that drum face it wants to stay there
-- until you let off the brakes all the way.

It's a pain in the rear, but it's not nearly as bad as brake fade on a
downhill, or jacknifing truck, trailer, and cargo. It's also something
that you get used to; you just have to allow a bit of extra distance for
a smooth stop, and accept the fact that you'll be lighting up one or
more trailer tires every once in a while.

(Hey, I do automatic control systems -- I'll bet there's a product in
there someplace, to make it all smoother. You'd need to find a cheap
way to sense the degree of braking you're getting at any moment, then
figure out how you're going to get product liability insurance for a
high-tech braking system that's installed in an aftermarket environment.)

--

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

Do you need to implement control loops in software?
"Applied Control Theory for Embedded Systems" gives you just what it says.
See details at http://www.wescottdesign.com/actfes/actfes.html

Tim Wescott wrote in news:SbudnbD_-
:

You'd need to find a cheap
way to sense the degree of braking you're getting at any moment, then
figure out how you're going to get product liability insurance for a
high-tech braking system that's installed in an aftermarket environment.

How cheap do you want?

Would ~$120 be about right?

The Jordan Ultima 2020 uses a steel cable that clamps to the brake pedal to
sense braking effort and applies current proportionately.

I've been using one for 6 years. I chose it because it would apply the
trailer's brakes even in the event of total hydraulic failure in the truck.
grin

The BrakeSmart uses a transducer mounted in the Master Cylinder to achieve
the same function as the Jordan's cable. This unit runs ~$350, IIRC.

Proportional braking isn't Rocket Science. grin

On Jul 14, 11:04 pm, "RAM³" wrote:
Tim Wescott wrote in news:SbudnbD_-
:

You'd need to find a cheap
way to sense the degree of braking you're getting at any moment, then
figure out how you're going to get product liability insurance for a
high-tech braking system that's installed in an aftermarket environment..

How cheap do you want?

Would ~$120 be about right?

The Jordan Ultima 2020 uses a steel cable that clamps to the brake pedal to
sense braking effort and applies current proportionately.

I've been using one for 6 years. I chose it because it would apply the
trailer's brakes even in the event of total hydraulic failure in the truck.
grin

The BrakeSmart uses a transducer mounted in the Master Cylinder to achieve
the same function as the Jordan's cable. This unit runs ~$350, IIRC.

Proportional braking isn't Rocket Science. grin

I kinda agree, and I miss the old line pressure based brake controller
I used to have. I think Tim is talking about closing the loop on the
electric brakes to prevent lockup, ie. antilock or ABS type control
with individual wheel speed feedback. This would be a great feature
if the basic archaic magnet/brake architecture could respond fast
enough. Probably could even figure a way to have the brake drum act
as a tone wheel modulating the DC brake current to provide the
feedback control signal without dedicated speed pickups.

On Tue, 15 Jul 2008 03:04:06 GMT, "RAM³"
wrote:

Tim Wescott wrote in news:SbudnbD_-
:

You'd need to find a cheap
way to sense the degree of braking you're getting at any moment, then
figure out how you're going to get product liability insurance for a
high-tech braking system that's installed in an aftermarket environment.

How cheap do you want?

Would ~$120 be about right?

The Jordan Ultima 2020 uses a steel cable that clamps to the brake pedal to
sense braking effort and applies current proportionately.

I've been using one for 6 years. I chose it because it would apply the
trailer's brakes even in the event of total hydraulic failure in the truck.
grin

The BrakeSmart uses a transducer mounted in the Master Cylinder to achieve
the same function as the Jordan's cable. This unit runs ~$350, IIRC.

Proportional braking isn't Rocket Science. grin

Problem with a pressure sensor in the brake line is that the car
makers will pass a brick if you propose tapping *anything* into the
hydraulics.

Like the good old controllers from 40 years ago that actually had a
little slave cylinder inside, that moved the actuating lever over and
progressively shorted out a wirewound resistor to increase braking
current - they were brain-dead simple, perfectly responsive, and
worked forever.

Why can't they build things using the KISS Principle anymore? Or at
least as much as you can in the age of electronics, using tried and
true components and intelligent design that has few points of failure.

I suppose they could put a strain gauge on the pedal arm, or a
pressure sense pad on the pedal, but that's getting involved.

-- Bruce --

RAM³ wrote:
Tim Wescott wrote in news:SbudnbD_-
:

You'd need to find a cheap
way to sense the degree of braking you're getting at any moment, then
figure out how you're going to get product liability insurance for a
high-tech braking system that's installed in an aftermarket environment.

How cheap do you want?

Would ~$120 be about right?

The Jordan Ultima 2020 uses a steel cable that clamps to the brake pedal to
sense braking effort and applies current proportionately.

I've been using one for 6 years. I chose it because it would apply the
trailer's brakes even in the event of total hydraulic failure in the truck.
grin

The BrakeSmart uses a transducer mounted in the Master Cylinder to achieve
the same function as the Jordan's cable. This unit runs ~$350, IIRC.

Proportional braking isn't Rocket Science. grin

Proportional current to the highly nonlinear electric brakes doesn't
give proportional braking.

My controller runs off of the hydraulics, it gives nicely proportional
drive to the trailer, and my brakes still 'stick' just like Ivan's.

So maybe it ain't rocket science, but it ain't as easy as you say.

--

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

Do you need to implement control loops in software?
"Applied Control Theory for Embedded Systems" gives you just what it says.
See details at http://www.wescottdesign.com/actfes/actfes.html

oldjag wrote:
On Jul 14, 11:04 pm, "RAM³" wrote:
Tim Wescott wrote in news:SbudnbD_-
:

You'd need to find a cheap
way to sense the degree of braking you're getting at any moment, then
figure out how you're going to get product liability insurance for a
high-tech braking system that's installed in an aftermarket environment.
How cheap do you want?

Would ~$120 be about right?

The Jordan Ultima 2020 uses a steel cable that clamps to the brake pedal to
sense braking effort and applies current proportionately.

I've been using one for 6 years. I chose it because it would apply the
trailer's brakes even in the event of total hydraulic failure in the truck.
grin

The BrakeSmart uses a transducer mounted in the Master Cylinder to achieve
the same function as the Jordan's cable. This unit runs ~$350, IIRC.

Proportional braking isn't Rocket Science. grin

I kinda agree, and I miss the old line pressure based brake controller
I used to have. I think Tim is talking about closing the loop on the
electric brakes to prevent lockup, ie. antilock or ABS type control
with individual wheel speed feedback. This would be a great feature
if the basic archaic magnet/brake architecture could respond fast
enough. Probably could even figure a way to have the brake drum act
as a tone wheel modulating the DC brake current to provide the
feedback control signal without dedicated speed pickups.

Well, feedback on the electric brakes so they don't have so much
hysteresis -- they should apply quick, not slowly wind up, and let go
_proportionally_ as you ease up off the pedal. I hadn't considered
anti-lock brakes.

I _think_ the magnet/brake architecture could be made to respond fast
enough, but you'd have to have some pretty severe gyrations of the
current to the magnet to effect smooth control at the shoes; with some
systems (particularly ones with sticky magnets or rust spots on the
friction surfaces) you may get some 'pumping' of the brakes.

Anti-lock brakes would be a nice plus to that, although the basic
magnetic brake actuator may not respond at all quickly enough for that.

--

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

Do you need to implement control loops in software?
"Applied Control Theory for Embedded Systems" gives you just what it says.
See details at http://www.wescottdesign.com/actfes/actfes.html

Tim Wescott wrote in
:

RAM³ wrote:
Tim Wescott wrote in news:SbudnbD_-
:

You'd need to find a cheap
way to sense the degree of braking you're getting at any moment,
then figure out how you're going to get product liability insurance
for a high-tech braking system that's installed in an aftermarket
environment.

How cheap do you want?

Would ~$120 be about right?

The Jordan Ultima 2020 uses a steel cable that clamps to the brake
pedal to sense braking effort and applies current proportionately.

I've been using one for 6 years. I chose it because it would apply
the trailer's brakes even in the event of total hydraulic failure in
the truck. grin

The BrakeSmart uses a transducer mounted in the Master Cylinder to
achieve the same function as the Jordan's cable. This unit runs
~$350, IIRC.

Proportional braking isn't Rocket Science. grin

Proportional current to the highly nonlinear electric brakes doesn't
give proportional braking.

My controller runs off of the hydraulics, it gives nicely proportional
drive to the trailer, and my brakes still 'stick' just like Ivan's.

So maybe it ain't rocket science, but it ain't as easy as you say.


Sounds like you need to check your adjustment on the BC.

On Tue, 15 Jul 2008 08:49:23 -0700, Tim Wescott
wrote:

RAM³ wrote:
Tim Wescott wrote in news:SbudnbD_-
:

You'd need to find a cheap
way to sense the degree of braking you're getting at any moment, then
figure out how you're going to get product liability insurance for a
high-tech braking system that's installed in an aftermarket environment.

How cheap do you want?

Would ~$120 be about right?

The Jordan Ultima 2020 uses a steel cable that clamps to the brake pedal to
sense braking effort and applies current proportionately.

I've been using one for 6 years. I chose it because it would apply the
trailer's brakes even in the event of total hydraulic failure in the truck.
grin

The BrakeSmart uses a transducer mounted in the Master Cylinder to achieve
the same function as the Jordan's cable. This unit runs ~$350, IIRC.

Proportional braking isn't Rocket Science. grin

Proportional current to the highly nonlinear electric brakes doesn't
give proportional braking.

My controller runs off of the hydraulics, it gives nicely proportional
drive to the trailer, and my brakes still 'stick' just like Ivan's.

So maybe it ain't rocket science, but it ain't as easy as you say.


If I was designing a proportional trailer brake, there are two things
that would be design "givens". No magnet applicator - hydraulic all
the way - and disc, not drum. Actually, using disc brakes it could be
electromechanical (servo motor) instead of hydraulic. Hydraulic would
be servo motor driven. Servo motor drives a drive screw to apply
master cyl pressure, with motor current monitored for feedback.
For direct servo brake, the servo motor would apply the piston
directly by drive screw.

Better yet, a "rotary solenoid" or "voice coil" type application
device operating an eccentric or "cam" applicator, again with current
sensing feedback to the controller.
** Posted from http://www.teranews.com **

clare at snyder dot ontario dot canada wrote in
:

On Tue, 15 Jul 2008 08:49:23 -0700, Tim Wescott
wrote:

RAM³ wrote:
Tim Wescott wrote in news:SbudnbD_-
:

You'd need to find a cheap
way to sense the degree of braking you're getting at any moment,
then figure out how you're going to get product liability insurance
for a high-tech braking system that's installed in an aftermarket
environment.

How cheap do you want?

Would ~$120 be about right?

The Jordan Ultima 2020 uses a steel cable that clamps to the brake
pedal to sense braking effort and applies current proportionately.

I've been using one for 6 years. I chose it because it would apply
the trailer's brakes even in the event of total hydraulic failure in
the truck. grin

The BrakeSmart uses a transducer mounted in the Master Cylinder to
achieve the same function as the Jordan's cable. This unit runs
~$350, IIRC.

Proportional braking isn't Rocket Science. grin

Proportional current to the highly nonlinear electric brakes doesn't
give proportional braking.

My controller runs off of the hydraulics, it gives nicely proportional
drive to the trailer, and my brakes still 'stick' just like Ivan's.

So maybe it ain't rocket science, but it ain't as easy as you say.


If I was designing a proportional trailer brake, there are two things
that would be design "givens". No magnet applicator - hydraulic all
the way - and disc, not drum. Actually, using disc brakes it could be
electromechanical (servo motor) instead of hydraulic. Hydraulic would
be servo motor driven. Servo motor drives a drive screw to apply
master cyl pressure, with motor current monitored for feedback.
For direct servo brake, the servo motor would apply the piston
directly by drive screw.

Better yet, a "rotary solenoid" or "voice coil" type application
device operating an eccentric or "cam" applicator, again with current
sensing feedback to the controller.
** Posted from http://www.teranews.com **


Electric-over-Hydraulic brakes are already on the market.

They're available now and have been for many years. Most, however, are
drums rather than disks due to the cost of calipers capable of handling
the braking for 10,000 or more pounds/axle.

Consider the surface area needed to supply that much friction.

On Wed, 16 Jul 2008 14:54:57 GMT, "RAM³"
wrote:


Electric-over-Hydraulic brakes are already on the market.

They're available now and have been for many years. Most, however, are
drums rather than disks due to the cost of calipers capable of handling
the braking for 10,000 or more pounds/axle.

Consider the surface area needed to supply that much friction.

Yet disc brakes are being used on many medium to light-heavy trucks.
Less fade problems. Easier service, and easier inspection.
Work better when wet too.
** Posted from http://www.teranews.com **

clare at snyder dot ontario dot canada wrote in
:

On Wed, 16 Jul 2008 14:54:57 GMT, "RAM³"
wrote:


Electric-over-Hydraulic brakes are already on the market.

They're available now and have been for many years. Most, however, are
drums rather than disks due to the cost of calipers capable of handling
the braking for 10,000 or more pounds/axle.

Consider the surface area needed to supply that much friction.

Yet disc brakes are being used on many medium to light-heavy trucks.
Less fade problems. Easier service, and easier inspection.
Work better when wet too.
** Posted from http://www.teranews.com **


Try looking at the trailers - those are the brakes that stop the load.