Validation of an ergonomic assessment method using Kinect data in real workplace conditions

- This paper proposes a RULA ergonomic assessment based on correct Kinect skeleton data.
- RULA scores provided by this method are evaluated in laboratory and real work conditions.
- In laboratory condition, Kinect-based joint angles were similar to grand truth data.
- In real work conditions, Kinect-based RULA assessment were in agreement with those of experts.
- Toward new continuous postural assessment thanks to 30 Hz Kinect measurements.

Evaluating potential musculoskeletal disorders risks in real workstations is challenging as the environment is cluttered, which makes it difficult to accurately assess workers' postures. Being marker-free and calibration-free, Microsoft Kinect is a promising device although it may be sensitive to occlusions. We propose and evaluate a RULA ergonomic assessment in real work conditions using recently published occlusion-resistant Kinect skeleton data correction. First, we compared postures estimated with this method to ground-truth data, in standardized laboratory conditions. Second, we compared RULA scores to those provided by two professional experts, in a non-laboratory cluttered workplace condition. The results show that the corrected Kinect data can provide more accurate RULA grand scores, even under sub-optimal conditions induced by the workplace environment. This study opens new perspectives in musculoskeletal risk assessment as it provides the ergonomists with 30 Hz continuous information that could be analyzed offline and in a real-time framework.