# Evaluating the Efficacy of a Passive Exoskeleton for Enhancing Ergonomics in Manufacturing
## 2 Methods
### Experiment, Apparatus, and Tasks  
We utilized the Ottobock BackX (Figure 1), a passive back-support exoskeleton designed for industrial applications, to perform simulated manual material handling (MMH) tasks. It was selected for its relevance and availability in our laboratory settings and based on its suitability for our study objectives. According to the device guidelines, this BExo is designed to alleviate gravity-induced forces on the lower back and reduces exertion during tasks involving stooping, lifting, and reaching by providing supportive force to user's chest and thighs. We followed the guidelines to adjust the exoskeleton based on each participant's physical characteristics, and all procedures of donning and doffing the exoskeleton were strictly adhered to during the experiments. Prior to the start of the experiment, the participants received an orientation session to become acquainted with the study protocol and equipment. They were provided with a consent form which detailed the study's scope and allowed them ample time to read and consent to their participation. All participants voluntarily agreed to participate and completed the consent forms before beginning the tasks. They were informed that they could withdraw from the study at any time without any consequences. However, all participants completed the tasks as planned. Upon concluding the experimental tasks, the participants were asked to fill out a survey to gather their feedback on the experience.  
The study involved the participants performing these tasks both with and without the exoskeleton support. The experiment comprised several distinct activities (Table 1). Breaks of an average of 3-5 min were provided throughout the session to prevent fatigue and ensure the participants' well-being. Initially, each participant performed a sequence that included walking for two minutes and then carrying and lifting a 7 kg (15.6 pound) box. These tasks were completed without the aid of the exoskeleton. The walking task consisted in the participants walking in the lab an 8 ft distance, back and forth, at their preferred walking speed. The carrying task involved moving the box between two points that were 2.6 m (8 ft) apart within the laboratory setting. Each task of carrying and lifting the box was repeated in two sets of three repetitions. The height at which the box was to be placed during the lifting tasks was fixed at 90 cm (2 ft). The scenarios and task execution are shown below in Figure 2 (photos published with participants' consent).  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Task** & **Repetitions** & **Duration** & **Specifications** \\ \hline Walking & 2 Trials (one with; one without BExo) & 2 min & Walk in the lab \\ \hline \multirow{2}{*}{Carrying a Box} & 2 Trials; 2 sets of 3 (one with; one without BExo) & Distance of 2.6 m (8 ft) & Box weight: 7 kg (15.6 lbs.) \\ \hline Lifting a Box & 2 Trials; 2 sets of 3 (one with; one without BExo) & At comfort pace & Box height placement: 90 cm (2 ft) \\ \hline \hline \end{tabular}
\end{table}
Table 1: Task specifications in the study.  
Figure 1: BExo used in the study; (**a**) back of the exoskeleton; (**b**) front of the exoskeleton.