Another, we are building a big flipper featherweight (low pressure) and we tested just the flipper at the weekend. First test was at 20 psi with nothing connected to the arm. With the ram not connected to the arm it flew over 180 degrees and hit the bench. We then fitted a bungee teather (needed anyway), We put a 5kg weight on the arm and put 20psi in it again and it went about 1 foot higher than the arm. After playing with the piviot point position we went upto 100 psi in small steps and got it to hit the roof, about 8 feet. The difference between 50 and 100 psi was not all that great (probably due to flow rate limitations) but found that adjusting the position of the pivot for less power but more speed was better up to a point. The whole thing was clamped to the bench but I would not like to test anymore until a drive system is sorted and we can test in the arena.

By the sounds of it this will not be anywhere near the power of some of the others but put a small piece of shrapnel on the arm weighting only a few hundard gramms and it will go very far. If theres not a top on the arena then even a few hundard grams will do serious harm landing on someones head. The problem is how will organisers ensure that arenas without tops will be safe without testing all filppers, disc etc.. to test their effectiveness. They will have to put alot of trust in the roboteers and limit the type of robots that can compete. RR arena has a top suffient for feathers with all weapon types that exsist at the moment and as most events use this arena then there is not a problem yet.