Microcontroller for Manipulator Robot

[hendrachubby]

Hi all,
I got a problem to control a manipulator robot ( Mitsubishi RV-M1 ) with serial communication, the robot it self has 5 DOF, 6 (24 Volt) DC Motor, 5 Encoder (200ppr 5Volt) and 2 (12 Volt) Electric brake. I got a problem to choose the suitable microcontroller, driver circuit for the motor and for the elecric brake. Can u suggest me, i prefer atmel microcontroller.
Thx for the help..

[ArcMan]

Are you looking for "hobby" type control, or is this for a "no kidding" industrial installation?

[hendrachubby]

The robot itself actually is a small sized industrial robot, i want it to control it like the manipulator robot in the video of robot arm tutorial. But the drive unit for this robot has been damaged and i need to rebuild a new controller, but i stuck when choosing the right microcontroller and driver for the motor. So i can say it's a "no kidding" industrial installation.

[Admin]

Whats your budget? Whats the motor current draw? What information do you plan to process on the mcu?

With 6 motors, that'll require 6 drivers . . .

[hendrachubby]

My budget is about $500, the motor current draw is 4Amps and in the MCU will process 5 incremental encoder and PWM for the motor simultaneously..it's for PID control of the robot...

[Admin]

Quadrature encoders or regular types?

If you want something quick and simple, use my Axon and control several Sabertooth motor drivers in RC mode. Its within your budget and super quick to hook up.

[Half Shell]

Quadrature encoders or regular types?

If you want something quick and simple, use my Axon and control several Sabertooth motor drivers in RC mode. Its within your budget and super quick to hook up.

I have no experience with the Axon, but it looks like an excellent micro controller that will help you get up and running quickly. My real experience, however, is with Dimension Engineering's Sabertooth motor drivers. I can not recommend them enough. If I'm not building my own motor driver I trust theirs first and foremost and have had, over many problems, exactly 1 of the drivers fail. Even then, it was only one channel on a dual channel driver AND they replaced it for free in a week.

[mbateman]

My experience with the Sabertooth in R/C mode was that it was very sensitive to the base period of the PWM. The only way I could get it to work reliably was with the timer-based PWM built-in to atMega. You can do this with the Axon, but it only pins out some of the PWM capable pins. You may not have enough if you use the Sabertooth for the brakes as well.  You can get 6 PWM outputs easily with E3-5 and H3-5. You have to burn another timer to get the one remaining on H6.

If you use a raw atMega640, you can have access to more, but then you would have to build your own board around it.

[Admin]

mbateman:
There is a trick to get an additional PWM pin. The green LED pin can do PWM, so just solder a wire to the top right of the 221 resistor right next to it. Unfortunately you'd lose control of the green LED as the trade off . . .

If I design a new Axon version, I'll definitely do a better job at pinning out all the PWM channels.