for Laurel (and QuadraRiSE as "Louie") -MRC

Penetrating Spines

One possible way to climb a surface is to dig spines into it and use them to pull yourself up. The penetrating spines need to be able to dig into the climbing surface and grab on without gouging or crumbling it.

RiSE Spines

Penetrating spines for climbing wood were developed for the RiSE robot. These spines were made out of heat-treated W1 and D2 steel (see SteelSelectionandTreatment). Generally it was found that the best spines were those that had cross sectional areas with flat bottoms. The flat bottom prevented the spine from gouging trenches into the wood while the robot climbed.

Z-man Spines

The Z-man project is also interested in penetrating spines for climbing. The most daunting material they want to try spines in is adobe since it tends to crumble when loaded.

A quick look through home improvement websites indicates that pre-drilling is important when trying to nail into adobe. Because of this, I wonder if it might be better to have a spine that removes material as it penetrates (like a saw blade) rather than simply wedging in (like a nail). I also want to look into drywall nails and figure out if/how they are better than normal nails for climbing adobe. Draper Labs is supposedly sending us a mini wall of DARPA-approved adobe...no idea if/when it’s going to arrive.
-- LaurelFullerton - 01 Aug 2008

I went to the hardware store on August 4th in search of adobe bricks and interesting nails. I tried two stores (Home Depot off the 101 and Ace Hardware in downtown Palo Alto. I did not find any adobe bricks. Home Depot had a variety of bricks in the landscaping/gardening section, but I don't think any of them were actual adobe. Hopefully the Darpa-approved test wall will arrive soon.

I did find a wide variety of nails at Ace Hardware. In addition to standard drywall nails, I found some nails with flutes cut into the length (similar to a screw with very shallow threads) as well as tack-like nails with a triangular cross section. When I get my hands on some adobe I plan to drive these in and see if any of them manage better than the others.
-- LaurelFullerton - 05 Aug 2008