Hello all,
I was thinking I would make a thread for showing my build process on my skid-steer all-electric robot mower.
I have done quite a lot of reading up on stuff, so maybe some other people can benefit from it. I know I was searching for threads like this, when I began my journey.
So Iām from Denmark, and all units will be metric - sorry 'bout that!
I have about 5000 m2 that need cutting divided on 3 lawns. There are quite a lot of obstacles, so thatās actually what Iām most concerned about with ArduPilot. Iāll have to see how difficult that is going to be to set up.
My plan right now is to make a 50-60cm dual blade mowing deck. The drive wheels will be the center point of the mower and the mowing deck will be placed in the front of the vehicle. The third wheel will be a standard castor wheel placed on the rear.
The setup will be as follows:
Pixhawk 6C Mini
UM982 for moving base line
F9P for ground station
Ć200 wheels (3D printed)
188W brushed DC motors (salvaged from old MiR robot) (gearing isnāt optimal, but theyāre way oversized, so I reckon I will be fine) (encoders will be connected to FC)
1kWh 24V/7S battery
30A RC PWM ESCs (cheap, chinese ESCs) https://www.aliexpress.com/item/1005001833856858.html
The idea is to have a bumper in the front that should register stuff or animals lying in the grass. Besides that, I plan to use 2-3 ultrasonic sensors to registers anything bigger in its way.
I also want to monitor the wheel current to check for a stuck robot. And monitor the cutting motors currents for a stuck blade or high grass (lower speed).
I am thinking of using an Arduino to control the āsafetyā features such as these above and tilting etc., and then it will send a stop command to the FC, if anything is wrong. Then it will require manual resuming before continuing.
So as of now, I havenāt gotten that far, but I am waiting for the FC and ESCs to arrive at my place, so I can test the motors and current build in manual control. I havenāt ordered GPS equipment yet. The grass doesnāt need cutting before May or something, so I should have time to get it running before that.
Hereās a video of how far Iāve gotten up until now:
Video: https://photos.app.goo.gl/qnsmzcFETCKLonCC6
So a few quick questions, if anyone has gotten this far:
- I have a Roboteq SDC2130 from a MiR robot, as well. The firmware is outdated though, and I canāt get my hands on a working update or the correct PC software. Does anybody have Roborun+ v1.6 on their computer they could send me? Then I will definitely use this instead of the cheap ESCs.
- Do I actually need an Arduino for controlling sensors? Is it possible to program such things in the FC?
- Can I also connect current sensors to the FC and program lowering of the driving speed, if the blade motors encounter tall grass? I have seen other people do this at least, but I am not sure how itās accomplished.
- I will have quite a lot of waypoints, as I see it with ājustā 50cm of mowing width. How does the limit of ~700 work? Can I raise it? Or is it possible to just send a single waypoint at a time from the base station?
If anybody has got some constructive feedback, then it is highly appreciated.