On/Off Control pf motor with ev3 while using pf battery for power

[knotian]

The solutions for using pf motors with ev3 that I've seen use the power from the ev3 battery to power the pf motors.

Is there a way to use the ev3 to control the on/off function of the pf motor while having the pf power still come from the pf battery?

[zux]

Well, the only thing I can think of is using Polarity Switch between BB and PF motor, but you would need to use use motor for the polarity switch... Or simply motorize BB switch.

Edited October 10, 2015 by zux

[knotian]

Thanks - The same thing can be accomplished by attaching a linear actuator to the battery switch. That still requires another motor.

I was hoping for something directly from the port of the EV3.

[Gonkius]

All PF motors, except the servo, doesn't have any electronics or switches internally. So there are no control signals available, only the middle 2 of the 4 wires are used. The servo motor however might be used as you suggest if a special wiring is done as this uses the power lines which are different from the control wires.

At least this is how I understand how things works in the PF world.

[MajorAlvega]

I was hoping for something directly from the port of the EV3.

Define «directly» :)

If you have a Power Functions IR receiver you can control it a 3rd party IR emitter connected to the EV3. Works with the default EV3 firmware.

If you have a SBrick you can control it with a USB Bluetooth 4.0 dongle connected to the EV3 but doesn't work with native EV3 firmware, you will need to run ev3dev (a Linux version made for the EV3).