Motors, Relays, Rules....
 

Well there are no small amount of questions, they have been building up over the past few weeks. We have already searched as best as we all know how on Team 1870 and have been unable to find anything

1) Where would we find the S-class rules...ie <S01>...<S02>....etc, for specific shooter rules....links? We are looking for shooter and pinch guard rules

2)When we hook up our flywheel(larger fisher price motor) to a spike relay, it blows the 20A fuse within 5 sec every time, we thought it might be a fuse manufacturing defect but after the third consistent result we decided against blowing up anymore fuses. I know it says 20A on the spike relay, but can we use any larger fuse without blowing the relay (mmmm...melty) are there any rules we could have missed forbidding it or is it just not such a good idea?
-could we wire the spike relays in parallel instead of using just one? Are there any safety concerns like fire/melty? Is it even possible?

3) Our temporary solution to the above problem was to use the Victor speed controller and that ran just fine with the joystick, but how would we get it to run fun forward or full reverse with the initial start on of the robot, we we did that we noticed that there was more and more drop off as we fed balls in quicker and this problem never happened with the battery/motors direct power. Are there any solutions to this drop off/inertia problem (the flywheel mass is heavy enough and when we used a fully charged battery, the drop off was less but still greater than before)? Also why is it doing this>

Re: Motors, Relays, Rules....
 

1) Rule <S01> through <S05> are "Safety" rules. You will find them "The Game" section of the manual (Section 4.3.1).

2) Don't connect your Fisher Price motor through the Spike relay. You must use a speed controller. This is both smart and required by the rules (according to Rule <R87> "CIM motors and Fisher-Price motors must be connected to Speed Controllers. They may not be connected to Relay Modules.").

3) Using the speed controller is the correct solution. If you are getting less than full performance from the motor/speed controller system, check your software to get sure that a full-power signal (255 for full forward or 0 for full reverse, or the other way around depending on how you have the motor wired) is being sent to the speed controller when the joystick (or other input device) is at the full range of motion.

4) Keep asking questions! We are all here to help.

-dave

Re: Motors, Relays, Rules....
 

Thank You very much for your help. I completely forgot about those rules with the Fischer Price and CIM with the Victors. Dang Thank you, we would have completely missed that one...yikes...that would have messed our robot up...well kinda.

Still the question remains does anyone have any idea how to set with the Victor's so that they turn and run automatically by themselves without any button pushing. I am unsure if our programmers know how to do this, but I thought I would ask just in case as I will not see them until Friday. If anyone has an idea please say so. Thanks

-Cody-

Re: Motors, Relays, Rules....
 

Yes, just have the software send the corresponding maximum value (0 or 255, depending on how you have the speed controllers wired) to the speed controller, and stand back.

-dave

Re: Motors, Relays, Rules....
 

Within the code where you put all the PWM=127 (ie PWM01=127), take the pwm you are using and make it equal either 0 or 255 (ie PWM01=0 or PWM01=255), also besure that it is remmed out when it says something like p1_x=pwm01

Sorry, I am about to sit down to work on more code and dont remember the numbers/letters exactly.

-Mike

Re: Motors, Relays, Rules....
 

You are running into a problem all of us will face this year. Some of your wheel is giving energy to the ball. In general terms you may need to rethink the design as you shoot more balls and the battery voltage gets lower during the match, this problem will get worse. You may want to design for a lower power setting to achieve the correct trajectory and then be able to bump it up as the battery voltage sags.
As to the original problem with the FP, current draw on those motor can be significantly higher than 20 amps with a stall current twice that amount. Breaker choice and wire size won't modify those numbers. Hence the rule where you must use a speed controller for this motor. All things being equal, with a speed controller and 20 amp breaker you will likely trip the breaker as well.