Society of Robots - Robot Forum

Electronics => Electronics => Topic started by: nadvee on May 11, 2014, 03:31:59 PM

Title: Picking Processors and Controllers
Post by: nadvee on May 11, 2014, 03:31:59 PM
My friend and I are currently working on building a robot which incorporates a lot of DC motors, as well as sensors and 3d mapping of surroundings.
What the robot is going to use is
- DC motors with torque output of 50lbs+, voltage is 12VDC, Quantity: 10
- Sensors are rotary encoders and gyroscopes (as many as the motor)
- 3d mapping (not sure how, as of now)
- Hydraulic Cylinder, Rotary and linear actuators.

So, right now the question comes down to, what kind of processors/ controllers can we use for the robot? We want a processors and controllers that are fast and is capable to meet our requirements. Currently, we are looking at PIC microcontrollers (still didn't decide or rather can't find the correct one) and Intel atom motherboards. If you have any information onto what we can do, please help. Thank you.
Title: Re: Picking Processors and Controllers
Post by: jwatte on May 12, 2014, 10:05:55 AM
A microcontroller and an Atom are very different things. The microcontroller is great at electrical interfacing, but terrible at anything processing heavy. The Atom is the opposite. Successful high-level system typically combine microcontrollers for the electrical signals, with high-power CPUs for the heavy signal processing lifting.

Regarding controllers "50 lbs+" says nothing, because torque is measured in force-times-distance, and you're just specifying weight (or, perhaps, force.) The thing that matters for a motor controller is the maximum current draw of the motor, which should be specified in the motor data sheet. You should size the controller for twice the maximum current, and twice the control voltage, because when turning around the power to the motor, you may temporarily see spikes that are twice your supply. Examples of high-power motor controllers include the Sabretooth line from Dimension Engineering, and the Roboclaw line from Orion Robotics. Both of those can be controlled from a PC or a microcontroller using USB or TTL serial. The Roboclaws also have encoder inputs and a closed-loop PID controller.