Cal Poly Engineering Project Assistance Needed


I am currently working on adaptive feeding device for my mechanical engineering senior project. The device will feed people at the touch of a button. My team needs to control 2 servo motors and 1 linear actuator for our project. We need basic help just getting the code started. The linear actuator needs 12 volts and 1 amp, and the servos need 5-6 volts and 1 amp. The arduino and the linear actuator are connected to the 12v battery, and the servos are connected to the 5v output of the arduino uno board. Is this correct or do the servos need a power supply independent of the arduino?

Any basic code help or general tips would be GREATLY APPRECIATED!!!

Thanks very much, look forward to talking with you!

John Cal Poly Mechanical Engineering

I would use a separate supply for the servos. Make sure it has a good heatsink. Running one amp through a 7805 chip without a heatsink will burn it up. You also want at least that much isolation to keep current transients from interfering with the Arduino. I would put a choke on both power supply lines. Radio Shack has some small toroids in a bag for a decent price. In general you want the power supply to your microcontroller board to be very, very clean. The easiest way to do that is to use a separate regulator for trouble-making devices.

You should also put at least a thousand microfarads of capacitance before the regulator for the servos. This will help a lot to quiet the 12 volt line.