What are the advantages of variable stiffness control?

Summary form only given. The role of stiffness modulation in limb movement control is discussed in light of recent measurements of the stiffness of the human elbow joint during free movement. The stiffness is found to be low during movement, in comparison to the stiffness measured under isometric conditions. Since reflexes and muscle co-activation determine the total stiffness, utilizing a low stiffness minimizes the danger of instability arising from feedback delays and the energy required for co-activation.<
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