Conversation

Replying to
And FINALLY, the full assembly is sorta done with all major linkages and joints represented. It was a bitch to get this right... there's like 6 ball joints, and 5 pin joints here.
Image
1
8
The thing is, attaching the 2 turnbuckles would immediately mangle the assembly into a weird train wreck. Since the geometry is coarse, all lengths are rough approximations, and OnShape doesn't allow ball joints to be constrained, the constraint solver creates pretzels.
1
1
And initially I had the turnbuckles set too long, so the thing would really contort. So I suppressed one end of each turnbuckle, rearranged the whole thing to look right, then manually adjusted the turnbuckle lengths and positions to be approximately right...
1
Then I unsuppressed end connections and the solver "found" the nearby solution and didn't pretzelize the design. Then I used the measuring tool to measure the turnbuckle length, and went back to the part subassembly and constrained cylindrical joint to be a few mm around that.
1
1
Effectively, instead of solving a hard 3d geometry problem to compute the right nominal length, I found it "experimentally" in the 3d CAD design. Now I have everything close enough that I can do projections and back out final actual geometry. 😎 🥳
2
9
Back to rover after 2 months. Finally got beaglebone blue to drive a motor. Result of a half day of work that should have been 20 minutes. 🤬
Embedded video
0:03
316 views
1
3
This Tweet was deleted by the Tweet author. Learn more
This Tweet was deleted by the Tweet author. Learn more