APM 2.6 Sabertooth and Kangaroo

I am brand new here, so if I am in the wrong place, let me know. I will start with the APM is amazing. It is everything I hoped it would be. I will fly it eventually but for now I will drive it.I have an Electric wheelchair with a 2x 60 amp Sabertooth controller with the Kangaroo motion control module and a APM 2.6. I am unable to find anyone using his configuration. So can someone point me in the right direction on how to get this working?
Connections to the APM how to configure APM to utilize the DE Arduino libraries are the first issues.
Thanx in advance

The APM2.6 can control the Sabertooth ESC through either its R/C mixing input (steering & throttle) or using the APM skid steering function and have the Sabertooth function as two independent motor controllers. Wiki: http://rover.ardupilot.com/wiki/apmrover-setup/
If you want to use the Kangaroo motion controller, you are going to have to tell us more about how it works to be able to help you out.
TCIII Developer

I really do want to use the Kangaroo as it handles all of the encoder inputs. Below is the blurb from the Diminsion Engineering web site. My goal is to have 4 modes :
1 R/C control
2 Local Joystick control (on the Bot)
3 Auto (arduopilot)
4 Laptop (running Higher level software thru arduopilot or other microcontroller if necessary)

[quote]Kangaroo x2 adds self-tuning feedback motion control to your Sabertooth or SyRen motor driver. It can be used with quadrature encoders or potentiometers to provide position or speed control. It supports one or two feedback channels.

Feedback control has always been highly desirable for mechanical systems. Being able to tell your device to move an exact amount, at a specific speed or to a certain position, and have it reliably and repeatably do so, regardless of the load or disturbances, has obvious benefits. However, PID and other controllers have to be carefully tuned to get acceptable results. Feedback tuning is difficult, time consuming and requires advanced math and physics knowledge.

Kangaroo x2 is the first self-tuning controller in its class. Instead of requiring you to measure, model and calculate the system, the controller itself will figure everything out after a few switch settings and button presses. In the time it takes to get a tasty snack, you can come back to a perfectly tuned system ready to accept your commands.

Instead of requiring you to use a microcontroller to do closed loop control, Kangaroo x2 works from analog and radio control sources as well as microcontrollers and computers. You can, for example, use it to build that two horsepower R/C servo you’ve always needed as the final piece of your doomsday device. Just remember who helped when the vaporizing starts.

During operation, you can command speeds, positions or combined commands like “move to 37 inches at a speed of 4 inches per second.” You can also have the Kangaroo x2 report back speeds and positions while it is running. A mixed mode allows for unstoppable mobile robots with differential drive or tank style steering.



I had an APM 2.5 going directly in to Sabertooth without Kangaroo module. I would be interested to see how you get on with your plans though as the Kangaroo sounds good.

Blog post & video here:

I am now using my APM in my UAV so it is not operational at the moment.

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We plan to add self tuning to the ArduRover2 code in the near future. I suspect that it will be on the agenda for early 2014.
TCIII Developer

Ah good good :slight_smile:. I am also interested in ability for rover to follow an AB line similar to agricultural tractor autopilots but I won’t put in feature requests until I have time to contribute to testing or docs or similar.

What are you trying to do with the Sabertooth / Kangaroo, and how is your system configured?

If you want speed control of a single motor, you can drive the Sabertooth in RC mode directly from the APM throttle channel. If you’re skid steering, you can either set up the APM for skid steer, and use the Sabertooth in standard mode, or run throttle and steering into the ST, and configure the ST to do the mixing.

The APM can do vehicle speed control (i.e. travel at 5 m/s) based on GPS. The Kangaroo will give you more precise speed control, but you need an encoder to feed back speed to the kangaroo.

If you give some more info, we may be able to help more.

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