A Systematic Review on Lower-Limb Industrial Exoskeletons: Evaluation Methods, Evidence, and Future Directions

• Published in: Annals of biomedical engineering Vol. 51; no. 8; pp. 1665 - 1682
• Main Authors: Kuber, Pranav Madhav, Alemi, Mohammad Mehdi, Rashedi, Ehsan
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 01.08.2023; Springer Nature B.V
• Subjects: Biochemistry; Biological and Medical Physics; Biomechanics; Biomedical and Life Sciences; Biomedical engineering; Biomedical Engineering and Bioengineering; Biomedicine; Biophysics; Classical Mechanics; Design; Design improvements; Devices; Engineering; Evaluation; Exoskeleton; Exoskeleton Device; Exoskeletons; Fatigue; Human subjects; Humans; Industry; Injuries; Limbs; Lower Extremity; Metabolic rate; Metabolism; Muscular fatigue; Plantar pressure; Posture; Product development; Review; Stability analysis; Standing Position; Systematic review; Thigh; Wearable technology; Biomechanics; Wearable Chair; Ergonomics; Squatting; Assistive Devices; Lower Body; Assessment; Workplace Injury; Physical Demand; Technology Acceptance
• DOI: 10.1007/s10439-023-03242-w
• ISSN: 0090-6964; 1573-9686

Industrial tasks that involve frequent sitting/standing transitions and squatting activities can benefit from lower-limb industrial exoskeletons; however, their use is not as widespread as their upper-body counterparts. In this review, we examined 23 articles that evaluated the effects of using Wearable Chair (WC) and Squat-assist (SA) exoskeletons. Evaluations mainly included assessment of muscular demands in the thigh, shank, and upper/lower back regions. Both types of devices were found to lessen muscular demands in the lower body by 30–90%. WCs also reduced low-back demands (~ 37%) and plantar pressure (54–80%) but caused discomfort/unsafe feeling in participants. To generalize outcomes, we suggest standardizing approaches used for evaluating the devices. Along with addressing low adoption through design upgrades (e.g., ground and body supports/attachments), we recommend that researchers thoroughly evaluate temporal effects on muscle fatigue, metabolic rate, and stability of wearers. Although lower-limb exoskeletons were found to be beneficial, discrepancies in experimental protocols (posture/task/measures) were discovered. We also suggest simulating more realistic conditions, such as walking/sitting interchangeability for WCs and lifting loads for SA devices. The presented outcomes could help improve the design/evaluation approaches, and implementation of lower limb wearable devices across industries.