My Stingray Look a Like Plywood Robotics Platform - Update 8 Real Brakes

Duane Degn

Cool brakes!

Thanks for the update. It's always fun to see others' robots.

Do your brakes still work well with the Banshee in motion? I'd think the momentum of the robot would make stopping the wheels harder with the robot in motion than when it's on the bench.

Did you consider using relays to short the power lines momentarily. I think erco is a fan of this approach (I haven't tried it myself). I haven't built a robot that so large it needs brakes,

If you get a chance, I'd love to see a video of your robot in action (using the brakes while driving around).

Thanks for taking time to document your work.

erco

Yes, I'm a staunch advocate (though some would say avocatus diaboli) of low-geared motors and dynamic braking, achieved on a DC motor by shorting the motor leads together (after disconnecting power!).

If you like your friction brake method, you can dramatically improve your braking/clamping force by pivot geometry and carefully shaping the contact patch shape to make your brakes "self-energizing". The brake is more like a cam which gets "sucked in" harder by the brakepad reaction. If you take it to the extreme, you can lock up your brakes violently with the lightest of touch (AKA a micro servo). Not recommended for the faint of heart.

http://en.wikipedia.org/wiki/Drum_brake

Whit

Cool brakes Tony. Does Banshee flip forward when you apply the brakes or do the wheel not stop so quickly if the robot is actually moving?

Martin_H

It's a shame that the HB-25's don't brake on the center pulse, because that's what CR servos do, and they're supposed to make DC motors controllable via servo pulses.