Objective and Subjective Evaluation of a Passive Exoskeleton for Upper Limbs

The aim of this study was to evaluate the Hapo ms, a passive upper limbs exoskeleton developed to assist workers for tasks with arms in front of the body. Twelve participants had to perform a static task, a manual handling task and a load carrying task two times: with and without the exoskeleton. In all cases subjective (perceived effort in arm and back areas, comfort) and objective (muscular activity, postural balance) criteria were evaluated. Results have shown a decrease in anterior deltoid (-12 to -18% depending of the task) and in biceps brachii (-19% to -33% depending of the task) muscular activity. No significant difference was pointed out in back muscle and postural balance was not significantly perturbed due to the wear of the exoskeleton. Finally, perceived effort reduction was observed during the three tasks (except in back area for task 1). To conclude, the Hapo ms seems well adapted to assist upper arms during tasks with arms in front of the body.

Prototype for Knee-load Relief through Ischiatic Support

Objective: The objective of this work was to develop a passive exoskeleton prototype for the relief of knee-load employing ischiatic body weight support. Methods and materials: A functional prototype was developed and tested with three volunteers to analyze its potential effectiveness and effects on gait kinematics. The performance of the prototype was assessed using motion capture and pressure mapping systems, and a testing bench for the study of ischiatic body weight. Results and discussion: The results of the tests indicate that the prototype allows reducing the load supported by the knees and does not have a significant effect on the kinematics of the hip and knee joints. The process allowed the designers to identify possibilities of improvement mainly on reducing the restrictions imposed by the prototype to the motion of the ankles, especially on the midstance of the support phase. Conclusions: The passive exoskeleton prototype developed for ischiatic body weight support allows setting different percentages of knee-load relief. The prototype does not have a significant effect on the kinematics of the hip and knee joints. Nevertheless, improvements must be performed to reduce the restrictions to the motion of the ankles.

Suggestions for the order of military exoskeletons classification

The article defines the role and place of exoskeletal structures for military purposes in the military equipment of military personnel, and provides a brief analysis of the functional tasks assigned to them. Based on the results of the analysis, a new formulation of the concept of «military exoskeletons» is proposed, and the order of their classification is recommended. Based on the practical experience of creating and using exoskeletons for military purposes, a general description of all the proposed classification groups and their features is given. Key words Military exoskeleton, military combat equipment, classification groups, active assault-type exoskeleton, passive exoskeleton, explosive exoskeleton, rigging exoskeleton, medical exoskeleton.

Introducing Exoskeletons into the Operating Room: A pilot study with vascular surgeons

The main goal of this pilot study was to create, implement and evaluate a strategy for introducing exoskeletons in the operating room (OR) at a quaternary care academic hospital. The strategy consisted of operating-room-specific considerations, introducing exoskeletons to surgeons, and a post-surgery survey. Three male attending vascular surgeons participated in eleven data collections to date. Low interference with surgeon’s ability to perform surgery was found for all surgical procedures, except for two open abdominal aortic procedures. The surgeons reported little to no limit on range of motion, except for one open abdominal aortic procedure. Lower than expected perceived improvement of ability to perform surgery and increase of physical comfort was self-reported. The responses indicate that the surgeons are willing to keep trying an exoskeleton intervention. In conclusion, a feasible process was created to introduce passive exoskeleton as an ergonomic intervention to vascular surgeons in their ORs.

Model-Based Design and Optimization of Passive Shoulder Exoskeletons

To physically assist workers in reducing musculoskeletal strain or to develop motor skills for patients with neuromuscular disabilities, recent research has focused on Exoskeletons (Exos). Designing active Exos is challenging due to the complex human geometric structure, the human-Exoskeleton wrench interaction, the kinematic constraints, and the selection of power source characteristics. Because of the portable advantages of passive Exos, designing a passive shoulder mechanism has been studied here. The study concentrates on modeling a 3D multibody upper-limb human-Exoskeleton, developing a procedure of analyzing optimal assistive torque profiles, and optimizing the passive mechanism features for desired tasks. The optimization objective is minimizing the human joint torques. For simulating the complex closed-loop multibody dynamics, differential-algebraic equations (DAE)s of motion have been generated and solved. Three different tasks have been considered, which are common in industrial environments: object manipulation, over-head work, and static pointing. The resulting assistive Exoskeleton’s elevation joint torque profile could decrease the specific task’s human shoulder torque. Since the passive mechanism produces a specific torque for a given elevation angle, the Exoskeleton is not versatile or optimal for different dynamic tasks. We concluded that designing a passive Exoskeleton for a wide range of dynamic applications is impossible. We hypothesize that augmenting an actuator to the mechanism can provide the necessary adjustment torque and versatility for multiple tasks.