Victor Brakes

[sciguy125]

Originally Posted by Alex698

I figure(correct me if you see errors), put a single-pole, double throw contact switch between motor, victor and leads to diodes then to a battery. By switching to the leads with diodes the motors are turned into generators by the forward motion of the robot. The diodes are so the battery doesn't back into the motors causing them to run at full.

I don't think you need the switch. There's some diodes in the transistors that will do the job. If all of the transistors are off, spinning the motors forces current into the supply.

[Al Skierkiewicz]

Originally Posted by Alex698

I don't know if this thought will help, but what about regenerative braking?

I figure(correct me if you see errors), put a single-pole, double throw contact switch between motor, victor and leads to diodes then to a battery. By switching to the leads with diodes the motors are turned into generators by the forward motion of the robot. The diodes are so the battery doesn't back into the motors causing them to run at full.

Alex,
The speed controllers have this feature built in but using a slightly different method. The current supplied by the motor used as a generator is dumped into the transistors in the controller which are acting as a short. The controller is an "H" bridge design. Imagine the "H" with the motor connected from the center of the left vertical to the center of the right vertical. The top and bottom of each vertical is a set of power MOSFETs. The top of both upper vertical bars are connected to the positive battery connector and the bottom of both lower verticals is connected to the negative battery connector. To turn the motor on in one direction, the transistors in the upper left and lower right corners are turned on. To reverse the direction of the motor, the upper right and lower left transistors are turned on. To vary speed, you add a switching waveform to turn the transistors on and off, with speed determined by the ratio of the ON time to OFF. To provide braking, turn ON both of the bottom sets of transistors. Since they are both connected to the negative battery terminal, they are shorted together and that produces a short across the motor.
By varying the pulse that enables the brake you could vary the braking force. As pointed out by others in this thread, the braking is dependent on rotation. The slower the motor is turning, the less current is being developed in the motor, and the less effective the braking becomes.

[gburlison]

Originally Posted by xtolbert_gators

How do u hook a victor up so that you can reverse the polarity and cause the motors to stop. Could this cause a type of brake?Could there be a way to include it into the programming so that we can control it from the control board?

In the distant past (2000) we used a globe motor to rotate a set of forklift type arms from a stowed position. As the arms passed vertical, gravity would take over and the arms desended quickly. The globe motor was programmed to move foreward fast and then switched to a slow reverse to counteract the effect of gravity. The arms then continued to rotate forward but the action was less stressful on the mechanical parts. We have since learned that it is better to use springs to balance arms.