I hope this message finds you all keeping well. I have just purchased the Lynxmotion A4WD1, managed to transfer over my setup from the previous rover & it’s working well. Only problem right now is it’s not turning 360 degrees on the spot. On my kitchen floor it can do it but not on carpet or grass.
I have provided some links I recorded. The first is someone else’s who has the same rover. It rotates just fine on carpet:
The following two links are my rover:
As you can see on the second link when I pick it up the wheels can turn in skid steer but not when it’s on the floor:
I was originally using a NiMH 7.2v 5000mAh battery which wasn’t enough for the rover. I then upgraded to a 14.8v 1300mAh battery and the rover managed to turn a couple of times in 360 degrees but the power depleted within minutes & couldn’t turn anymore. I would really appreciate your help in what I need to do. I would like to use this ideally on grass so that’s my target.
Thank you so much for your time & I look forward to your advice.
I would suggest you to take a look at the Switch #6. It could be caused by a misconfiguration.
Switch 6: R/C Mode/Microcontroller mode select If switch 6 is in the UP position, then the Sabertooth is in standard R/C mode. This mode is designed to be used with a hobby-style transmitter and receiver. It automatically calibrates the control center and endpoints to maximize stick usage. It also enables a Timeout Failsafe, which will shut down the motors if the Sabertooth stops receiving correct signals from the receiver. If switch 6 is set in the DOWN position, then Microcontroller mode is enabled. This disables the Timeout Failsafe and auto-calibration. This means that the Sabertooth will continue to drive the motor according to the last command until another command is given. If the control link is possible unreliable – like a radio - then this can be dangerous due to the robot not stopping. However, it is extremely convenient if you are controlling the Sabertooth from a microcontroller. In this case, commanding the controller can be done with as little as three lines of code. Output_High(Pin connected to S1) Delay(1000us to 2000us) Output_Low(Pin connected to S1)
Thank you very much for your reply. I have realised that the power supply from my Lipo was too low to support the 12v Motors on the rover. I have now upgraded to 11.1v Lipo & all is working much better. I will try the sixth switch still once I’m at my rover and report back with the results. Might make it even better🤞🏼
I also wanted to ask if you have any advice/experience in setting up the A4WD1 with the Sabertooth on Mission Planner?
On Mission Planner there are parameters & tuning configurations but I need to understand how to tune the A4WD1 to work with a Pixhawk on Auto Missions. So far I have been unsuccessful in doing so.
Here is an example of the tuning page on MP so I need to find the right parameters to input into this to make the A4WD1 work properly:
