Muscle Synergies Heavily Influence the Neural Control of Arm Endpoint Stiffness and Energy Consumption
Fig 9
Some arm postures compromise the ability to minimize energy.
Black regions indicate locations in the workspace (i.e, limb postures) where meeting the desired endpoint stiffness leaves no room to minimize energy. These regions are also heavily influenced by the desired stiffness ellipse shape (i.e., eccentricity). Even when minimizing energy is possible, that ability seldom reaches a reduction of 50% and is typically < 10–30%.