OUR SABERTOOTH WIRES SMOKE! I WILL GIVE DETAILS BELLOW. PLEASE COMMENT IF YOU HAVE ANY IDEAS ON WHAT IS WRONG.*
I am designing and building a custom claw for my MATE rov team, and we need a linear actuator for it, so we chose a cheap one off amazon: Amazon.com
We have waterproofed it and now we ran into the problem of controlling it. We bought this Sabertooth motor controller for it: https://www.robotshop.com/products/sabertooth-dual-12a-regenerative-motor-driver
We wired it as follows: Power:
We have the power coming from a stacked port inside the enclosure to the Sabertooth’s B+ and B- ports. Connection:
We have the S2 signal and ground wires on the Sabertooth going to the Navigator flight controller. Actuator:
We have the actuator plugged into the M2A and M2B ports on the Sabertooth.
PROBLEM:
Whenever we plug in the rov to a 12v battery, what we have always used and what is required for our competition, the Navigator does not turn on and beep like it should, but the Sabertooth ground (black) wire going to the Navigator starts MELTING and SMOKING!
We tried unplugging the Sabertooth S2 from the Navigator and when we turned back on power, the RED power wire started SMOKING and the Navigator did not turn on.
Once we unplugged the Sabertooth completely (from the power and the Navigator), and we plugged the rov back into the battery, the Navigator turned on and beeped and started working like normal.
WHAT IS GOING ON??? Please comment if you have any ideas or need any details.
Are you sure that you’ve got the correct polarity hookups at the Sabertooth power B+ and B-? It sounds like you have either a reversed power connection or a ground loop issue here. I don’t know what you mean when you say the Sabertooth power is coming from a “stacked port”. Sabertooth B- should be at the same potential as ground on the Navigator board. I would check the power supply you’re using for the Sabertooth with a voltmeter, paying particular attention to the polarity. If it looks right, then measure between the negative terminal of that power supply (which will go to the Sabertooth B-) and the ground of the Navigator board. That should be zero.
I am pretty sure that we have it wired up right b+ b-. Could you post what the correct way is? I am going to a robotics meeting tomorrow so I can check then. By a stacked port I mean we ran out of power “ports” (places that the power splits to all 6 t200 thrusters and an m200 motor) we had no more “ports” left on the power splitter inside the enclosure, so we stacked the power wires on the wires for the m200 motor. It is somewhat hard to explain, so I could take pictures of it tomorrow and put them in a comment.
Please help if you can! My robotics team has 2 weeks until competition and we need your help! The most helpful thing right now is any ideas you have of what is going wrong.
Hi @GradyJS -
Have you reviewed the vendor’s documentation? How did you waterproof the actuator, and does it work if directly connected to the battery?
I’d guess that your dip switches may not be configured correctly, or something is off in your wiring. Pictures are always helpful when troubleshooting! I assume you’re connecting the ESCs of t200/m200 motors to power all on the same bus, and not connecitng the 3 phase motor wires together…
Yes, I have read the vendor’s documentation multiple times, and we used the actuator last year for a vertical profiling float. It was connected to an ESP32 and a reversing relay that would control power to it. I will get some pictures today and put them in a comment. For the ESCs, they all work fine as well as the motors, but yes, they are all powered on the same bus, and we ran out of ports on the bus, so we stacked the crimped Sabertooth power wires on top of some other wires. (I will get pictures of this) We built and competed with this ROV last year and had no problems because we were not using the actuator to move our gripper in and out, so the navigator, all 6 thrusters, and the m200 motor have all worked for over a year. All that is messing up is the sabertooth. I will get plenty of pictures and put them in the comments later (around 5 to 6).
If you have any ideas on what is wrong before or after I put the pictures in, please comment. That is the most helpful thing for my team right now.