Accuracy of force and center of pressure measures of the Wii Balance Board

Abstract

The Nintendo Wii Balance Board (WBB) is increasingly used as an inexpensive force plate for assessment of postural control; however, no documentation of force and COP accuracy and reliability is publicly available. Therefore, we performed a standard measurement uncertainty analysis on 3 lightly and 6 heavily used WBBs to provide future users with information about the repeatability and accuracy of the WBB force and COP measurements. Across WBBs, we found the total uncertainty of force measurements to be within ±9.1 N, and of COP location within ±4.1 mm. However, repeatability of a single measurement within a board was better (4.5 N, 1.5 mm), suggesting that the WBB is best used for relative measures using the same device, rather than absolute measurement across devices. Internally stored calibration values were comparable to those determined experimentally. Further, heavy wear did not significantly degrade performance. In combination with prior evaluation of WBB performance and published standards for measuring human balance, our study provides necessary information to evaluate the use of the WBB for analysis of human balance control. We suggest the WBB may be useful for low-resolution measurements, but should not be considered as a replacement for laboratory-grade force plates.

Dynamic Single-Leg Postural Control Is Impaired Bilaterally Following Anterior Cruciate Ligament Reconstruction: Implications for Reinjury Risk

“…For example, WBB measurements may be associated with greater uncertainty than laboratorygrade equipment. 6 However, the greatest variability has been observed across different WBBs, and the use of a single WBB, as was the case in the current study, optimized repeatability. 6 Importantly, the accuracy of CoP measurements does not appear to diminish with repeated use of a single WBB over time.…”

“…6 However, the greatest variability has been observed across different WBBs, and the use of a single WBB, as was the case in the current study, optimized repeatability. 6 Importantly, the accuracy of CoP measurements does not appear to diminish with repeated use of a single WBB over time. 6 While other issues such as sampling-rate irregularity via the Bluetooth protocol are inherent in the system, excellent validity and reliability results using an identical protocol support its use.…”

“…26 The same WBB was used for all participants in the current study to optimize certainty of force measurements. 6 The longitudinal axis of the board was aligned to the longitudinal axis of the foot (second toe to midcalcaneus). A heightadjustable plinth was positioned behind each participant so that the edge of the plinth was vertically aligned with the heel of the test foot.…”

Posturography using the Wii Balance Board™

“…A sample of healthy subjects and individuals with stroke were assessed with the system and compared, as a proof of the clinical utility of the assessment tool. In spite of the fact that the WBB seems to not be as accurate as laboratory grade force platforms [30], it appears sufficient for detecting postural reactions during posturography tests. However, the particular hardware architecture of each posturography system can lead to different measurements [30], therefore the WBB-based posturography system should be used for relative rather than for absolute measurements.…”

Calibration procedure and uncertainty analysis of an electronic scale based on two-current source supplied circuit

“…Such devices are used in the measurements of ground reaction forces [11,12]. The system will be integrated with a PC with the use of the LabVIEW software.…”