Standard Performance Test of Wearable Robots for Lumbar Support

Wearable robots for lumbar support (hereafter, WRLS) can reduce the users’ lumbar stress and the risk of their back injuries. Although several products have already been put on the market, consumers and distributors have difficulty comparing their performance during assistance because they are currently not measured in a standardized manner. To solve this problem, this letter designs a standard performance test for WRLS. In the test, a testing machine makes reference movements imitating trunk movements with knee and hip joints during manual handling such as lowering down, holding, and raising up. Then, two performance metrics: Assistive Torque Index (ATI) and Lumbar Compression Reduction (LCR) are evaluated. The human experiments show that the reference movements are ergonomically plausible to mimic the actual motion of humans. The robot experiments indicate the feasibility of the test itself. The performance test has already become a part of JIS B 8456-1:2017 (a Japanese product standard for WRLS) and is to be a part of ISO 18646-4.

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