Abstract
In the industry 4.0 scenario, Human-Robot Collaboration (HRC) plays a key role in factories to reduce cost, increase production and help aged and/or sick workers maintain their job. The approaches of the ISO 11228 series commonly used for biomechanical risk assessment cannot be applied in Industry 4.0 as they do not involve interaction between workers and HRC technologies. The use of wearable sensor networks and software for biomechanical risk assessment could help us have a more reliable idea on the e^ectiveness of collaborative robot (coBots) in reducing biomechanical load for workers. The aim of the present study was to investigate some biomechanical parameters with 3D Static Strenght Prediction Program (3DSSPP) software, on workers executing a practical manual material handling task, by comparing a dual arm cobot assisted scenario with a no cobot scenario. The parameters investigated were percent of Maximum Voluntary Contraction, Maximum static (continuous) allowed exertion time, Low back spine orthogonal compression forces at L4/L5 level and Strength Percent Capable. In this study, we calculated mean and the standard deviation (SD) values from eleven participants for some 3DSSPP parameters. We considered the following parameters: Percent of Maximum Voluntary Contraction (%MVC), Maximum static allowed exertion time (MaxST), Low back spine compression forces (L4Ort) and Strength Percent Capable (SPC). The advantages in introducing the cobot, ac-cording to our statistics, concern trunk flexion (SPC from 85.8% without cobot to 95.2%; %MVC from 63.5% without cobot Vs. 43.4%; MaxST from 33.9s without cobot to 86.2s), left shoulder abdo-adduction (%MVC from 46.1% without cobot Vs. 32.6%; MaxST from 32.7s without cobot to 65s) and right shoulder abdo-adduction (%MVC from 43.9% without cobot Vs. 30.0%; MaxST from 37.2s without cobot to 70.7s) in Phase 1; right shoulder humeral rotation (%MVC from 68.4% without cobot Vs. 7.4%; MaxST from 873.0s without cobot to 125.2s), right shoulder abdo-adduction (%MVC from 31.0% without cobot Vs. 18.3%; MaxST from 60.3s without cobot to 183.6s)and right wrist flex/extension rotation (%MVC from 50.2% without cobot Vs. 3.0%; MaxST from 58.8s without cobot to 1200.0s) in Phase 2. Moreover, Phase 3, consisting of another manual handling, would be removed by using the cobot. In summary using the cobot in this industrial scenario, would reduce the biomechanical risk for workers particularly for trunk, both shoulders and right wrist. Finally, 3DSSPP software could be an easy, fast and costless tools for biomechanical risk assessment in industry 4.0 scenario where ISO 11228 series can't be applied for occupational medicine physicians and health and safety technicians and helping employers to justify a long-term investment.