Building a lawn mower rover. It’s wheelbase is about 1 meter wide, 1.3 long. There are two driven wheels at the back, and a pair of caster wheels at the front. The cutting deck will be mounted in the middle.
Question is, should it go forward, or backward? I’ve noticed if it goes caster wheels first, a bump can cause the caster to steer the rover slight off course, where I think if the casters were at the rear, it would have less authority ( and a longer wheel base ). Also, if it goes backwards the drive wheels are on uncut grass, so maybe better traction?
What would be the pro’s con’s on either direction.
Second question, how do I tell the rover when end is which? I mean, its going casters forward by default, is there a simple variable I can change to say the other end if the front of the vehicle, or it is more involved.
I live in Central Florida and have very thick St. Augustine grass in my front yard that does not mat down easily. Due to the fact that the grass is very thick with long runners I have found that the smaller front wheels (casters) would bog down in the grass as the larger back drive wheels pushed them forward. Therefore, I have the back drive wheels pulling the lawnmower forward with the smaller front wheels in the back supporting the cutting head deck.
On the other hand, if you have fine bladed grass that mats down easily, you can probably have the rear drive wheels easily push the front caster wheels through the grass without any effort.
I think the only thing you need to change is the FC orientation (AHRS yaw /180) and the front becomes the back so probably easy to try both and see what works best. Im guessing driving wheels first may be best.
Push or pull makes little difference to the software. A front drive with castering rear wheels might perform very slightly better coming out of tight/pivoted turns.
Be aware that many mower decks are a bit directional, so you may see decreased cut quality if you drive it backwards from the expected direction of travel.
Since it’s a new build, just mount the autopilot with the arrow in the direction of intended travel, and don’t worry about the orientation parameters.