3 ml metal support brackets and beefer compression springs. Works great!
Also where it is positioned it doesn’t affect the camera view.
You’re halfway to making a rear bumper for collision detection!
Any suggestions on moles? Traps, bait, and pellets don’t work.
Back to designing a motion activated thermite surprise.
great idea for a lawn striper
Care to share materials involved or how you attached it to the core?
Hello 
There are two bolts on either side of the back of the core. Likely for the blower. I used those to affix the two support plates.
The 2 short and center roller are 1 1/2 inch ABS? Tubing. I 3d printed filler tubes with an interior diameter of the threaded rod. I also had some bearings but they might be optional. Then I put a nut on either end.
You might want to refer to the previous pictures 
The roller seems to work pretty well at flattening the bumps.
If this makes no sense, feel free to inquire further 
Oh happy day would that be if we actually could rear mount the leaf blower…. I seem to recall that was a feature…
I’m telling you, I think it could be done with a custom job
How are the support plates connected to the compression springs and the roller itself? another mounting plate? is everything welded together?
There is a nob cut into the mount for the top of the spring and a small sliding plate with a spring nob on top. The sliding plate is held in place by the spring and the rollers on either side. I also put large washers on either end of each roller.
I hope this makes sense.
Ah, so it’s one solid piece with notches cut out on the top and bottom for the spring? Are you worried about metal fatigue and fracturing of the uncut side which is toward the front of Yarbo?
I used 3 mm plate steel and most of the stress seems to be upward since the rollers roll and the spring absorbs the impacts.
I can post a picture of the steel template I used.
I can tell you the moles are annoyed by the roller. 12 hours after I rolled a big population, they had aggressively reopened the area. Continued annoyance, might get them to move on to the neighbors
So I see the roller fits in the bottom notch.
What holds the small slider piece in, that seems to be held in by…nothing?
It’s magic
The sliders are held in place by the rollers and washers on either side, the metal of the mount and the downward pressure of the spring.
There is nowhere for the slider to go.
I hope this makes sense.
Actually the threaded bar fits in the bottom of the notch.