Evaluation of the Leap Motion Controller during the performance of visually-guided upper limb movements


E. Niechwiej-Szwedo, Gonzalez, D. , Nouredanesh, M. , and Tung, J. , “Evaluation of the Leap Motion Controller during the performance of visually-guided upper limb movements”, PloS one, 2018.


Kinematic analysis of upper limb reaching provides insight into the central nervous
system control of movements. Until recently, kinematic examination of motor control
has been limited to studies conducted in traditional research laboratories because
motion capture equipment used for data collection is not easily portable and expensive.
A recently developed markerless system, the Leap Motion Controller (LMC), is a
portable and inexpensive tracking device that allows recording of 3D hand and finger
position. The main goal of this study was to assess the concurrent reliability and
validity of the LMC as compared to the Optotrak, a criterion-standard motion capture
system, for measures of temporal accuracy and peak velocity during the performance
of upper limb, visually-guided movements. In experiment 1, 14 participants executed
aiming movements to visual targets presented on a computer monitor. Bland-Altman
analysis was conducted to assess the validity and limits of agreement for measures of
temporal accuracy (movement time, duration of deceleration interval), peak velocity,
and spatial accuracy (endpoint accuracy). In experiment 2, 15 participants performed a
Fitts' type aiming task in order to assess whether the LMC is capable of assessing a
well-known speed-accuracy trade-off relationship. Experiment 3 assessed the temporal
coordination pattern during the performance of a sequence consisting of a reaching,
grasping, and placement task in 15 participants. Based on the results from the 3
experiments, the average temporal error in movement time was 40±44 ms, and the
error in peak velocity was 0.024±0.103 m/s. The limits of agreement between the LMC
and Optotrak for spatial accuracy measures ranged between 2-5 cm. The LMC system
is a low-cost, highly portable system, which could facilitate collection of temporal, but
not spatial kinematic data outside of the traditional laboratory settings.


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Last updated on 05/14/2018