Jaguars not functioning with CIM motors

[vraimondi94]

My team decided to go with a two motor drive train using tankdrive. However, every time we try to run our robot the robot moves only a little bit and then the jaguars reset themselves. After the 3 secs the robot moves sluggish and will only move forward when you gently tilt the joystick forward. I am not too sure if this is an electrical problem or programming problem. I also saw that the jaguars resetting might be due to the CIM motor taking on too much or the jaguars drawing too much current. Any advice would help.

[kevin.li.rit]

Can you provide more details or a picture of how the drive is set up?

Also check to see if it is a dead battery issue...

[RyanN]

Originally Posted by vraimondi94

My team decided to go with a two motor drive train using tankdrive. However, every time we try to run our robot the robot moves only a little bit and then the jaguars reset themselves. After the 3 secs the robot moves sluggish and will only move forward when you gently tilt the joystick forward. I am not too sure if this is an electrical problem or programming problem. I also saw that the jaguars resetting might be due to the CIM motor taking on too much or the jaguars drawing too much current. Any advice would help.

It's definitely electrical from the sounds of it.

Tug on all the connections leading to the Jaguar, and also do a load test on your battery, or try a different battery. There is excessive resistance somewhere in the electrical path.

[slijin]

It sounds more like an engineering problem to me. Your CIMs are likely tripping the Jaguars' over current switches and causing them to shut off. Most teams have 4-CIM drivetrains precisely because it's difficult for 2 to continuously output enough power at 40A to drive the robot. You'll need to either 1) reduce the power needed to drive your robot or 2) add power to the drivetrain

Observe and describe the action of the Jaguars' LEDs to confirm; they should turn to slowly blinking red when the Jaguars "reset".

[billbo911]

Are you using CAN or PWM to control the Jags?
Jags resetting is rare. It could be the breakers tripping then resetting.

Either way, taking a good look at the drive train is well worth the effort. Is it binding? Try running the CIMs without the chains, that might give you a good way to determine where the trouble might be. If it is still tripping off, the transmissions might be binding. Maybe reduce to just the CIMs without any load at all. Somewhere along the way, you should be able to find your problem

[robokiller]

I recently had a similar problem in the past when I tried to run the electronics board off of a power supply that couldn't take the load.

when I tried to power the cims over 20% the jags would flash a red light and every five seconds the cims would give a pulse of light.

I had to replace the power supply with a regular battery. Im guessing you need to try another battery or charge the one you have .

[vraimondi94]

The battery we used were fully charged and we are using PWM cables also our other jaguars we are using to shoot the ball are experiencing this problem. The robot is using 6 wheel drive with chains.

[vraimondi94]

Also we ran the robot without chains and tipped it to one side then the other and it runs fine but when on the floor it's terrible. The lights on the jaguars turn green going forward but then turn yellow mid drive and stops

[FrankJ]

Sounds like your CIMs do not have enough power for your drive train. Tank drive is very power hungry which is one of the reasons you do not see it much in First competitions. Assuming you do not have excessive friction from misalignment, etc: you will have to increase the gear reduction.

The jag LED will flash slow red/yellow on current fault. Solid yellow is a zero command

[Al Skierkiewicz]

Vin,
Tank drive will put the CIM motors into near stall when you try to turn. Since you describe using other CIMs for your ball shooter, we expect that you are using only two CIMs for drive. If the CIMs run fine when you remove the chain connecting the components you may have some serious bearing issues. Either the chains are not aligned or the weight of the robot cause significant friction when the robot is one the floor. However, what you describe also occurs when the Crio senses that the power supply is falling to below 5.5 volts. There are a few possibilities for this.
1. You have a loose connection or poor crimp on the #6 wiring from the battery to the PD. Check all connections to be sure the hardware is tight.
2. On rare occasions the 120 amp breaker is defective. If you tap on the red button very lightly and the lights blink, you have a bad breaker.
3. Use an voltmeter to measure the voltage at the input to the PD. (the two lugs connected to the battery and breaker) You should see somewhere in the range of 7-12 volts when you try to drive. If this value jumps down to 5 volts or lower, something is wrong. It might be that the charger is not working. If you are using the First charger, make sure that the buttons are pressed for 12 volts and 6 amp charge.
4.. Check for the +24 volt LED on the end of the PD where the Crio is connected. Does it blink off when you have a problem?

[Marc P.]

You mentioned you were using chains to drive the wheels. Do you know what kind of gearbox and/or what sprocket sizes you're using on the motor side and on the wheel side? It's possible your drive train is geared too fast, and the CIM motors can't pull enough current to accelerate before the jaguars enter the over-current protection mode.