Sudden turn in the opposite direction

I made a boat with 2 thruster t200 connected and selected the boat frame in pixhawk, I assigned the value 73 to the servo1 function and 74 to the servo3 function. In my tests, when I make a left or right turn while on the last throttle, one of the engines suddenly tries to turn in the opposite direction in order to perform the left or right movement, and I guess that’s why the battery is protecting itself and resetting itself. For example, when the last throttle is going forward, I move slightly to the left and the battery cuts the power. What is the cause of this problem and how can I solve it, is there a parameter in Pixhawk that will prevent the motors from suddenly stopping and running in the opposite direction?

what motor controllers are you using and what battery are you using, I assume it has a BMS if its cutting off?

Bluerobotics basic esc, there is bms in the battery, what I was wondering is that the two motors draw 60 amps at full throttle, there are no power cuts when making sudden forward and backward movements at half power. but I’m experiencing these at the last throttle, I solved this problem by lowering the pwm values ​​of the engines. I need to use a battery with a higher current output to be able to use full throttle, right?
Also, is there a parameter in pixhawk that will prevent sudden movements in the opposite direction?
an inexperienced user can make such moves, so if I can’t do this easily with pixhawk, I need to write a code to check it

What mode are you using? If you are using MANUAL mode, there are few protections against sudden motion, and the mixing can indeed cause some sudden opposing motion when transitioning between reverse and forward throttle if any steering input is present on a skid steered vehicle.

I use manual mode, there are two motors, bms protects itself as one of the motors suddenly reverses when going right or left in forward or reverse gas, what protections do you suggest?

Use more care when driving in manual mode, and do not input any steering commands when switching between reverse and forward throttle.

Tune your vehicle such that you can avoid the use of manual mode.

If you continue to run into situations where the BMS goes into protection mode, I’d suggest that you have a poorly designed electrical system rather than blaming the firmware.

what size battery and BMS specifically are you using.

We use a 250Ah battery, I don’t know about BMS, but we told the manufacturer to increase the protection current in software. I’ll post back here when our issue is resolved. Also, when I drive the boat in ACRO Mode, I experience less power cuts, but there are still cuts, as a last resort, I will increase the current level that the BMS protects itself and test it.

they should be able to tell you what the battery is specified to handle. another option would be to put a small capacitor bank between the escs and battery to soak up the surge, I assume your battery is 12v?

battery max 25.2V, I will apply your advice, if I get a remarkable result, I will inform you again, thank you

You would need 2 of those capacitor banks in series to run in a 24v system.

I wonder if you are experiencing the same problem I had… But I’m not sure as your description is a little bit confusing to me… But it sounds similar…

Here’s the link to my thread:

The fix for me was to reverse chanel 3 in servo output and set pilot steer to 3

I’m not an expert but maybe it’ll help :slight_smile:

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