Three-wheeled rover with skid steering and servo controlled tailwheel

ArduRover Rover 3.3 / 3.4
21

Hello Sebastian,

sorry to bother you.

Did you had chance to see my e-mail?

Many thanks. Best regards.

Andrea

22

Hi Andrea,

you wrote me an email?

23

Hello Sebastian,

Yes, this below. Best regards.

Andrea

Ciao Sebastian,

It is true. TX was mixed up.

I cleaned it, switched off and configured the VESC like two indipendent VESCs (is the Pixhawk controlling both wheels speed in order to avoid motor damages?).

Now rover is working in manual mode and with servo output in PassTru.

Still not working in Throttle right (or left). I still do not see green bars moving at Servo output.

Are there other reasons behind not working of Throttle output?

Could the rover be used in Auto mode and make a mission with the PassTru output (even if it is not the proper setup)?

Many thanks. Regards.

Andrea

24

Hi Andrea,

I answered this 2 days ago here in the forum:

25

Hey Sebastian,

Iā€™m currently working on a 3 wheeled rover similar to your own with the rear tail wheel. Iā€™ve spent the last few days trying to find some methods for calculating the rear wheel angle based on the skid steer differentials, with limited success. Would you be willing to share some insights or snippets/code for the Arduino that does these calculations?

Thanks in advance,
Ryan

26

@megatr0nxx0rz Sure, no problem, here is the link:

https://drive.google.com/drive/folders/1L3o9hxNcE0uGqgJtVdrNTTBiOHdgMApT?usp=sharing

I am no programmer, so the code may be a bit ugly, but it works.
I am now using a Lua script running on the flightcontroller to control the tailwheel. The script is there, too.
Since the Lua script takes all the values directly from the firmware, it avoids the noise in the PWM signal going to the arduino. This results in a much smoother control and less jitter/jerking. If you have a flightcontroller able to run Lua scripts, I would use this.

1 Like
27

Wow, thanks a lot mate! I really appreciate it, while I have dabbled in coding and have been able to write some functional programs, I certainly wouldnā€™t consider myself a programmer either.
Iā€™ve got a good starting point now!

Thanks again, and cheers for the tips

28

Nice project. Are original motor drivers from hoverboard usable?

Thanks.

29

I can not help you with that question. I bought the motors seperatly. I use them with VESCs.

30

Thank you for your quick reply.