I was able to set up this ESC (HGLRC Zeus 60A ESC BL32) to make it work with the M200 motors. The ESC was set to allow for Bidirectional3D motion to allow for CW and CCW rotation, but I noticed that the M200 is asymmetric with regards to the RPM, in one direction vs the other (The motor would move faster in one direction vs the opposite direction). I looked into the M200 Performance Chart and that aligned with my observation. Is there a way to overcome this asymmetry?
I am currently testing a custom built ROV (with the blueROV2 heavy configuration) using 8 T200 thrusters with the BlueRobotics Basic ESCs. I looked into the T200 performance chart too and noticed it also has a bias (in terms of RPM). How did you guys overcome this bias so that the ROV moves backward and forward at the same speed? I am planning to replace the BlueRobotics Basic ESC with this ESC (HGLRC Zeus 60A ESC BL32) due to spatial constraints.
It would be really helpful to have a discussion about this! Thank you in advance.
The asymmetry you’re referring to is due to the propeller used, and not the motor itself! The M200 test data was collected with the weedless prop, which is optimized for forward thrust for usage on the BlueBoat. T200s have a different, 3 blade design that does try to be more symmetrical, but it still has a bias in one direction.
The BlueROV2 goes as fast forward as it does in reverse, because it has two thrusters facing each direction - canceling out the bias!
That ESC is quite small - I hope you can remove the heat from it efficiently! It defintely won’t have the cooling that is typical for its application in small quadcopters - and will be outputting a lot more power!
Thank you so much for your insights on the T200s and how the biases are cancelled out. In theory, swapping over to the ESC (HGLRC one) from the BlueRobotics Basic should be plug and play, a point to note is that the HGLRC esc is configured the same way the Basic is configured.
As for the M200s. I am using the M200 as a rotational actuator, not as a thruster.
I was testing my M200 motor connected to a 3D printed wheel to see the difference between the directional rotations, that’s when I found out one direction was quicker than the other.
It is quite important (for my use case) that the “forward” and “backward” rotation is similar.
That’s unusual enough that I’d suspect your test setup - how are you measuring RPM, and is the M200 running in air or water for the test? Can you share pictures and a more in depth description of both your test setup and target application? What difference in RPM are you quantifying? If you run the test in the opposite order, do the results stay consistent?