title: Development and validity of an instrumented handbike: initial results of propulsion kinetics.
abstract: OBJECTIVE
  To develop an instrumented handbike system to measure the forces applied to the handgrip during handbiking.
  
  
  METHODS
  A 6 degrees of freedom force sensor was built into the handgrip of an attach-unit handbike, together with two optical encoders to measure the orientation of the handgrip and crank in space. Linearity, precision, and percent error were determined for static and dynamic tests.
  
  
  RESULTS
  High linearity was demonstrated for both the static and the dynamic condition (r=1.01). Precision was high under the static condition (standard deviation of 0.2N), however the precision decreased with higher loads during the dynamic condition. Percent error values were between 0.3 and 5.1%.
  
  
  CONCLUSIONS
  This is the first instrumented handbike system that can register 3-dimensional forces. It can be concluded that the instrumented handbike system allows for an accurate force analysis based on forces registered at the handle bars.
authors.affiliation: Swiss Paraplegic Research, Guido A. Zächstrasse 4, Nottwil, Switzerland. stefan.vandrongelen@paranet.ch
authors.forename: Stefan
authors.initials: S
authors.lastname: van Drongelen
authors.forename: Jos
authors.initials: J
authors.lastname: van den Berg
authors.forename: Ursina
authors.initials: U
authors.lastname: Arnet
authors.forename: Dirkjan H E J
authors.initials: DH
authors.lastname: Veeger
authors.forename: Lucas H V
authors.initials: LH
authors.lastname: van der Woude
mesh_terms: D001642:Bicycling; D004867:Equipment Design; D006225:Hand; D006801:Humans; D007700:Kinetics; D055595:Mechanical Phenomena; D015203:Reproducibility of Results