programmable ESC's

[romac]

Hi guys
I am looking for a different type of programable ESC. I use motor controllers in the Industrial Automation Industry and they are fully programable.

I am looking for an RC ESC that will give me the ability to set up Torque Control or Speed Control or a combination of both. I wish to build a RC with independent 4 wheel drive. This means 4 ESC controllers controlled by a master controller. The possition of the steering would then be able to be relayed to each motor independentlly, this means that the inner wheels could be slowed down or the outer wheels spedup when cornering. This would eliminate the dreaded difflock 'go straight' when turning a corner, allowing much tighter corners with much less tyre wear. The idea of Torque control would mean any wheel without traction would not spin wildly but rather turn slowly until traction is avaliable and would only supply enough power to prevent wheel spin. If speed control is used you could have all the wheel spin you would like.
There are other advantages as well but I think this is enough to get the idea I have accross.

[SMR 510RR]

Holmes would probably be the guy to talk to about this, he has the most experience with stuff like this.

I have read about people trying this a couple times and I dont think I have seen anyone successfully complete their project so I wish you good luck. I believe the part that kills the idea is all the extra weight and the lack of gear reduction possible in the confined area between the motor and wheel.

[Docwolf]

the brushlesshobbies ESC has a lot the settings you want, i assume you are then going to use a micro controller of some sort to manage control between the 4 ESC? very cool man, I can't wait see how this works out.

[romac]

I have done this on a full scale car, the only problem I was faced with there was the cost of the LiFePO4 battery pack - way beyond my piggy banks limits so I had to abandon the project.
My idea was to build about a 1/5 model, there should be enough space for all the bits and pieces.
I want to use planetry gear boxes on the motors, this may require special engineering but that is ok as it is one of the privelages of running and Industrial Automation and Industrial Electronics business is I have access to the right equiptment.
The suspention I have in mind will be a radical change from the conventional, I know there will be some experementing before I woulf be happy and I also want to include 4 wheel steering.
I am not sure if I will use a micro controller or mini PLC as the master controller, I will decide later as I let my ideas grow/change as things progress. The programming is usually the easyest and most flexable part of a project.

[Docwolf]

This needs be based on a warthog as that how the rig was originally designed.

[romac]

hmm what is a Warthog, my project is not a copy of anyone elses work but a continuation of what I had started with my full scale car. The 4 wheel drive system works, tested. The trick is to now make it fit the RC world.

[ik632]

I'd think you could use some sort of mixing in the radio to handle the regular drive. Take a 2 esc system for example. You could set it up like the systems for tracked vehicles. When you pull the trigger both go forward. Then turn the wheel and it slows one side until it eventually brakes, and then reverses. This would handle the inner and outer wheels going a different speed and you could also have the steering channel mapped to a servo as well. This would give you regular servo steering and you'd get the independent wheel speed control.

For torque control I don't know that any of the hobby stuff we use has that.

[YJ_Driver]

Originally Posted by ik632

I'd think you could use some sort of mixing in the radio to handle the regular drive. Take a 2 esc system for example. You could set it up like the systems for tracked vehicles. When you pull the trigger both go forward. Then turn the wheel and it slows one side until it eventually brakes, and then reverses. This would handle the inner and outer wheels going a different speed and you could also have the steering channel mapped to a servo as well. This would give you regular servo steering and you'd get the independent wheel speed control.

For torque control I don't know that any of the hobby stuff we use has that.

He's trying to do a lot more than control the speed of each side. If the front left wheel has traction he doesn't want the rear left to spin super fast. He wants individual wheel RPM control based on what the other wheels are doing.

I've often dreamed of doing something like this in RC, but I just don't have the time to make any attempt.

Romac, I don't think the RC hobby has what you're looking for. At best some ESCs, like the Castle Creations Mamba Max Pro, has a programmable torque limit, but that's a set maximum meant to avoid wheel spin on a race car or driveline breakage. As mentioned above JohnRobHolmes here on the board might be a good first contact, or may even do something custom.

Good luck, and if you do start this build please post it on this forum

[romac]

Thanks for the encouragement YJ, I like the 'pebble pounder' bit. I must admit of late I have been trying slightly larger 'pebbels', ones tha a normal car would not be able to get over.
I am going to approach Novak as I have a Balistic 13.5T motor combo for my Wraith, just maybe they would produce such an ESC.
What may not be clear is that I am also working on a suspention and stearing system. I hope I get it right because if I do it will mean way better ground clearence. I am looking for second hand, even broken shocks, diffs, axels etc from 10th and 16th scale. I find it easer to work with parts even if broken as this gives a better perspective of size and shape. Living in South Africa sometimes has its down side, there are not too many in my area that do Crawlers so finding bits and pieces may not happen. That means I will probably have to do with wood carvings of the parts of my Wraith.