Beefing up the Hip Suspension


dsc03364Once I started to traverse over obstacles with a fully loaded torso and the robot was being shaken I noticed that the gas shocks were not keeping the torso/hip level. At first I thought I had sheared the cross bolt to the hip motor cam on the Dewert motor but upon careful examination that was not the case. The gas shocks were not strong enough so I  replaced the 4420 gas shocks (which were only giving approximately 25lbs of lift support each) with the Mightly lift model numbers E 95859 (4048)  which yielded approximately 60 lbs of lift for each shock. (remember there are 2 shocks used for the hip)However this was too much for the dewert motor to move but it did flex the aluminum sub waist plate! So I tried 40 lbs shocks. Those work good but they are not the best. I need to review the physics books to figure out the optimal strut strength for a 100 lb load.  There has to be a math equation to figure this out. In the mean time I lengthened the long arm of the hip rotation assembly and shortened the cam to decrease the fulcrum effect on the motor so the downward weight of the torso would not have as great of an affect on the motor (so the motor would be more effective as a brake when not in use). It still may be necessary to find a motor that has a brake but time will tell……


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