We introduce new compliance models for LADD transmissions which reduce inelastic model errors by an order of magnitude. These errors are due to fiber bending, as opposed to the traditionally assumed fiber elasticity. The new LADD models are experimentally verified and applied to the modeling of concentric LADD devices. The new models are essential for the design of LADD based systems, the online estimation of LADD forces, and accurate control. Details of the design, manufacture and break-in phenomena are given, as well as the first experimental measurement of LADD efficiency, which is better than 90%.

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