Bionic Arm Might Go Into Clinical Trials 107
prostoalex writes "The bionic arm project sponsored by DARPA is nearing completion, and might undergo clinical trials. 'The arm has motor control fine enough for test subjects to pluck chocolate-covered coffee beans one by one, pick up a power drill, unlock a door, and shake a hand. Six preconfigured grip settings make this possible, with names like chuck grip, key grip, and power grip. The different grips are shortcuts for the main operations humans perform daily.'"
Re:Power grip (Score:4, Insightful)
There are a couple reasons. (Score:5, Insightful)
The power of the arm is limited by the amount of power the motors in the arm can generate, which in turn is limited by the size of the battery in the arm. Since the power is limited, the amount of force that can be applied by the arm is also limited, as the arm will need to be able move at a reasonable speed. When you see a hydraulic arm performing tasks of immense strength, it is important to note the motor attached to it. In most cases an internal combustion engine would be too heavy to use in a bionic arm (and too noisy).
More importantly, the "core strength" of the person is unaffected by the arm, so the force applied in most tasks (tasks requiring the muscles in the back and legs) would be limited by the person's other muscles in the event that the arm were significantly stronger. Of course if the arm is not able to apply as much force as the rest of the body, the arm becomes the limiting factor.
Also, the connection of the arm to the person could be the limiting factor, depending on how it attached.
Re:Kung fu grip (Score:2, Insightful)