Hi,
simple question.
How can I disarm not only Throttle but also Steering?
In my current setup everything works fine except that when I will disarm my Rover, it is still possible to TURN. Rover is tank like construction but not skid steering (I am using ESC that can handle that).
Ok, solved…
Seems the simplest approach is to change to ThrottleLeft and THrottleRight and reconfigure ESC;)
Yes the steering output is not disabled by disarming, i assume you were using a dual ESC with a mixer built in?
I’m wondering if there is actually a way to do this that doesn’t involve a change to the steering approach. I’m using a mid-wheel wheelchair base which is pretty dangerous when “steering” only.
Would be nice if I could disable steering while disarmed, or even disable all servo outputs while disarmed.
Use a safety switch. Use the following parameters to suit your needs:
BRD_SAFETY_DEFLT
BRD_SAFETY_MASK
BRD_SAFETYOPTION
I assume the safety switch must be physically located on the vehicle. Is there a way to configure this behavior from the remote? Essentially a servo output kill switch.
Thanks for the prompt response.
Exactly what dangerous behavior are you observing? If it’s a skid steered vehicle (which it appears to be), all drive motor output is disabled while disarmed.
I suppose you could create a Steering channel mix that disables (fixes at 1500us) the output when the Arming Switch is off. Assuming you are using an Arming switch. Not a very elegant solution though.
I can also envision a scripted solution, but that’s very inelegant. I suspect it’s a case of motor driver config that we can overcome.
To give some context as to what I’m trying to do, I’m a teacher introducing robotics into my engineering classroom so student safety is a priority (as is predicting how a student might create a problem).
I’m using a RadioMaster Zorro, Cube Orange + and Sabertooth 2x32 motor controller. Currently, the aileron and throttle channels (zorro) are being used as the ground steering and throttle servo outputs from the cube. The Sabertooth is then mixing the channels to drive the motors.
The safety issue is that the vehicle is quite heavy and can “steer” (aka spin around) at high speed even when disarmed.
Perhaps the best solution is to drive it tank style if I can’t easily disable the steering.
This is actually the answer I was hoping to hear. Your vehicle is set up incorrectly for skid steering.
First, set your Sabretooth driver to independent mode via the DIP switches.
Next, set ArduPilot to use ThrottleLeft and ThrottleRight outputs. Ensure you have motor direction set correctly by using Mission Planner’s motor test page. See here.
Lastly, see this link for the steering mix. PILOT_STEER_TYPE=0 should result in the same RC steering behavior as you have now.
Superb. Exactly what I needed. Much appreciated.