Dr.-Ing. Christian Krämer, Dipl.-Ing. (2014)
Title of the Dissertation:
Ergonomic optimisation of the handbike drive concept
In order to optimise the performance of the system athlete-handbike, aerodynamic properties in a wind tunnel, gross efficiency for three different propulsive movements, maximal power with respect to crank length and –width and the effect of the handle angle were examined. Aerodynamic drag was crucial regarding performance and was decreased by lowering the crankcase, the sitting position of the handbiker, the backrest and by using a narrow crank width. Concerning aerodynamics optimal crank length must be adopted to the athlete`s arm length. A higher gross efficiency for the round motion was found compared to other propulsive movements. Contrary to crank width, the crank length showed a significant effect to maximum handcycling power. Highest power was reached with a crank length of 26% of forward reach and a crank width of 85% of shoulder breadth. The +30° pronated handle angle was optimal with respect to performed work.
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