A Focused Review on Soft Robotic Exosuits for Sitting to Standing Transfers

摘要

Sit-to-stand (STS) and sit-to-walk (STW) are vital daily tasks that affect mobility, independence, fall risk, and quality of life. Therefore, it is important to aid older adults or movement impaired individuals in performing sitting to standing transitions. As such, wearable soft robotic exosuits hold potential in assisting these movements as they can overcome the limitations posed by traditional mechanical exoskeletons. Soft exosuits work in parallel with user’s muscles, are lightweight, compliant, comfortable, and can provide variable stiffness and torque actuation. This reduces the metabolic cost of movement along with the risk of joint misalignment and musculoskeletal injury, as commonly experienced with exoskeletons. Hence, this review aims to provide an overview of the existing and recent soft robotic exosuits that aid STS and STW transitions. A general description of each device is presented while categorizing the exosuits as active and passive, and subdividing as expansive, tensile, and hybrid based on their actuation technology. The core technologies governing soft exosuits are discussed with focus on the physical human–robot interface (HRI), actuation methods, sensors, movement intention detection, and control architecture. The benefits and limitations of each type of exosuit are presented along with future prospectives and areas of improvement for these core technologies. This includes maximizing HRI stiffness while maintaining comfort and designing high hip and knee torque actuators to meet the requirements of STS and STW. Additionally, early and autonomous intention detection should be explored with advanced mid-level control architectures for estimating user-targeted joint torques, based on movement phases, execution strategies, anthropometry, and biomechanics.