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Controller modul for servo motors


#1

Hi community,
i want control a robot arm with 5 servo Motors (24V/2A). I want to use a spider or raptor board to do this. Wich is the best way or modul?
Thx for each tip
René


#2

DC or Stepper?

https://www.ghielectronics.com/catalog/product/315 --DC

https://www.ghielectronics.com/catalog/product/418 --Stepper


#3

Hi Bill,
I thought i need a special modul to control servo motors?
Thx


#4

Servo motors are PWM controlled. Don’t need a special module for that just some break out modules.


#5

@ Architect - Not strictly true. Standard RC servo’s are generally PWM but others can be serial.

@ dutzend - do you have a datasheet as 24v servo’s aint hobby jobs…


#6

Hi Architect,
thx for answer. I love this community. I MUST order tomorrow the moduls for 10 Robot arms with each 5 servos. I read in this Forum, some People try use the pulse in out modul to control the servos. I dont know how can i use only breakout moduls.
Thx René


#7

@ Bill: I want to build new Controllers for 10 Mitsubishi RV-M1 Robot arms. It is real no Hobby Job… I try to get a data sheet for the Motors…


#8

@ Bill Gates - I agree, datasheet should clarify that.


#9

From a very brief scan of the manual it looks like dc motors, quadrature encoders and some photo cells…

will be a fun project :slight_smile:


#10

@ dutzend - Is this a hobby project? I have a background in industrial robotics, so I have a pretty good idea of the challenges that lie ahead when designing a controller for these arms. You’ll have to deal with forward and inverse kinematics, motor dynamics, inductive spikes, brake actuation, calibration, homing (if incremental encoders are involved) or memory backup (if pseudo-absolute encoders are used), safety features (emergency stop, etc.). You’ll probably even have to create your own parser if you want the robot motions to be user-programmable.

If it’s for a hobby, you’ve got an exciting voyage of discovery ahead! :slight_smile:

If it’s for a serious purpose, perhaps you should look at the industrial controllers intended for these arms? They would be more reliable and should already meet various safety requirements. Plus, these industrial controllers should already have advanced features built-in like continuous-path trajectory control, which would be a real pain to program from scratch. We’re talking multiple nested PIDs, starting from the inner motor torque PID, to the motor velocity PID, to the motor position PID. Then you’ll have to deal with end-effector offsets, various orthogonal transforms and other kinematic operations. Hundreds of man-hours of work will likely be involved.