The crawler kit was a big pain to build, but it looks cool! It is essential to use the correct screws and nuts exactly as described in the instructions. Long screws and lock nuts are at the "knees," tapping screws in the pivots, and a nice comfortable drilled hole for the servo horn.
CODE! The robot is functionally identical to the standard "navigation with whiskers" bot but the whiskers are higher from the ground and bounce up and down. In general - it is far less reliable. Any code included for turns should have durations about four to six times longer to allow for the added turning time of the crawler.
- If you break your servo horn while cutting/drilling the extra space for the bolt, don't worry too much: The other three spokes will do just fine. If you completely break your servo horn, the horns that came with the original BOE Shield kit work fine.
- Don't let the diagram on the middle legs confuse you - they're both assembled the same way.
- Double check your washers before tightening the bolts on the middle legs. The one closest to the servo horn is a 1/8" spacer and looks twice as thick as the other nylon washers.
- Needle-nose pliers are very useful in tightening those lock nuts - but don't over-tighten them!A good measure its to tighten them just enough to allow the friction of a leg to keep it from spinning downward with gravity, then slightly loosen it from there.
- My crawler kit was four washers short. I easily found matching nylon washers at Lowes (Hillman #6 nylon flat washers)