Designing Brake Circuit for Motor w/ 24V Battery & 0-5V Joystick

[opmal7]

I am working on a project that uses two electric motors to control an elevation/traverse system. A problem with the motor that controls the traverse system is that it is able to be back-driven. To eliminate the back-driving, I will be adding an electric motor brake to mount on the the shaft that sticks out of the back end of the motor (typically where an encoder would mount).

The motor brake will be engaged when no voltage is supplied, and will disengage when 24VDC is applied. The motor itself also runs on 24VDC. I need to be able to supply voltage to the motor brake slightly before (~100-200 ms) applying it to the motor. The circuit includes a 24V battery, which feeds into a motor controller, and I am using a 0-5V analog joystick to control the speed of the motor. Ideally, when I move the joystick a signal would be sent to the motor brake to disengage, and then motor and joystick would operate as normal.

My background is more mechanical than electrical, and I'm hoping maybe one of you electrical buffs can give me some ideas or point me in the right direction. If any more details about the system are needed, let me know and I'll be happy to elaborate. Thanks!

 

[Tom.G]

The usual practice is that the brake winding is low impedance (large wire) and in series with the motor. That way the motor inrush current releases the brake quickly at startup. The other obvious advantage is that no extra circuitry or wiring is needed.