Dexterous actuation

• We address the actuation problem in compact multi-degree-of-freedom systems.
• We define Actuation Dexterity to evaluate the total actuation solution.
• Using artificial hands as a context we base our study on 36 different projects.
• We extract 48 evaluation criteria and test them on five case studies.
• We discuss the impact of this approach on the device design process.

Methods that have been developed for actuation system evaluation are normally generic, and primarily intended to facilitate actuator selection. Here, we address specifically those engineering devices that exhibit multiple-degree-of-freedom motions under space and weight constraints, and focus on the evaluation of the total actuation solution. We suggest a new measure that we provisionally call ‘Actuation Dexterity’, which interrogates the effectiveness of this total solution and serves as a design support tool. The new concept is developed in the context of artificial hands, and the approach is based on the review and analysis of thirty-six different artificial hand projects described in the literature. We have identified forty-eight unique evaluation criteria that are relevant to the actuation of devices of this type, and have devised a scoring method that permits the quantification of the actuation dexterity of a given device. We have tested this approach by evaluating and quantifying the actuation dexterity of five different artificial hands from the literature. Finally, we discuss the implications of this approach to the design process, and the portability of the approach between different device types.