Mechanical and Control Design of an Industrial Exoskeleton for Advanced Human Empowering in Heavy Parts Manipulation Tasks

Abstract

Exoskeleton robots are a rising technology in industrial contexts to assist humans in onerous applications. Mechanical and control design solutions are intensively investigated to achieve a high performance human-robot collaboration (e.g., transparency, ergonomics, safety, etc.). However, the most of the investigated solutions involve high-cost hardware, complex design solutions and standard actuation. Moreover, state-of-the-art empowering controllers do not allow for online assistance regulation and do not embed advanced safety rules. In the presented work, an industrial exoskeleton with high payload ratio for lifting and transportation of heavy parts is proposed. A low-cost mechanical design solution is described, exploiting compliant actuation at the shoulder joint to increase safety in human-robot cooperation. A hierarchic model-based controller with embedded safety rules is then proposed (including the modeling of the compliant actuator) to actively assist the human while executing the task. An inner optimal controller is proposed for trajectory tracking, while an outer safety-based fuzzy logic controller is proposed to online deform the task trajectory on the basis of the human’s intention of motion. A gain scheduler is also designed to calculate the inner optimal control gains on the basis of the performed trajectory. Simulations have been performed in order to validate the performance of the proposed device, showing promising results. The prototype is under realization.

Advances in Mechanical Systems Dynamics

“…Namely, the development of adaptive behavioral models, the design of cognitive architectures, and the ability to establish empathy with the user. Another emerging technology for assistive robotics is reported in [16]. In particular, this paper addresses a low-cost mechanical design solution exploiting compliant actuation at the shoulder joint to increase safety in human-robot cooperation of an Industrial Exoskeleton for Advanced Human Empowering in Heavy Parts Manipulation Tasks.…”

Sensors and Actuation Technologies in Exoskeletons: A Review

“…Similarly, different technologies are used for sensing purposes in exoskeletons, such as measures relating to the movement of specific limbs [ 18 ], forces or torques exchanged between device and user, bio-signals, such as electromyography signals (EMGs) [ 19 ], electroencephalography signals (EEGs) and mechanomyography signals (MMG) to be used for device control or validation [ 20 , 21 , 22 ], etc.…”

Human Stiffness Perception and Learning in Interacting With Compliant Environments

“…Although there are a few studies investigating human haptic perception using linear and nonlinear materials ( Hartman et al, 2016 ; Wu and Klatzky, 2018 ; Guang et al, 2019 ), it is still unclear whether the brain understands the profile itself or not. Understanding the brain mechanism is important for designing systems optimally in human-machine interaction, for example, in virtual reality rehabilitation ( Levac et al, 2019 ), robot-assisted rehabilitation ( Gasperina et al, 2021 ), and human-robot collaborative tasks ( Mauri et al, 2019 ; Roveda et al, 2019 ).…”