In recent years, more and more research has begun to focus on the flexible and lightweight design of wearable robots. During this process, many novel concepts and achievements have been continuously made and shown to the public, while new problems have emerged at the same time, which need to be solved. In this paper, we give an overview of the development status of soft wearable robots for human movement assistance. On the basis of a clear definition, we perform a system classification according to the target assisted joint and attempt to describe the overall prototype design level in related fields. Additionally, it is necessary to sort out the latest research progress of key technologies such as structure, actuation, control and evaluation, thereby analyzing the design ideas and basic characteristics of them. Finally, we discuss the possible application fields, and propose the main challenges of this valuable research direction.

The laryngeal tissue is sensitive to the operating force of the surgical instrument in the tissue resection. A large operating force may cause rupture of the vocal cords and surrounding tissues, which affect the patients’ normal voice. However, a small operating force cannot achieve tissue resection. Based on experience, surgeons can estimate the operating force in the process of using a surgical robot. The estimated operating force is usually inaccurate, which may increase the failure rate of surgery. Therefore, a fiber Bragg gratings (FBGs)-based 3-D force sensing sensor for the surgical robot, which consists of two flexible hinges in series is designed. And the force sensing model is constructed through mechanical modeling and temperature decoupling algorithm. The experimental results show that the designed sensor has a resolution of 14.3, 9.7, and 13.8 mN for external forces ${F_{x}},{F_{y}}$ , and ${F_{z}}$ , respectively. The proposed mechanism has good axial and lateral force sensing capability. In the experiment of simulating diseased tissue with the silicone-steel ball, the designed sensor can accurately determine the position of the steel ball, which verifies the effectiveness and feasibility of the designed FBG sensor in force perception.

To overcome the limitations of conventional bistable mechanisms, this paper proposes a novel type of bistable mechanism with linear negative stiffness and large in-plane lateral stiffness. By connecting the novel negative-stiffness mechanism in parallel with a positive-stiffness mechanism, a novel quasi-zero stiffness compliant mechanism is developed, which has good axial guidance capability and in-plane lateral anti-interference capability. Analytical models based on a comprehensive elliptic integral solution of bistable mechanism are established and then the stiffness curves of both conventional and novel bistable mechanisms are analyzed. The quasi-zero stiffness characteristic and High-Static-Low-Dynamic-Stiffness characteristic of the novel compliant mechanism are investigated and its application in constant-force mechanism and vibration isolator is discussed. A prototype with adjustable load-carrying capacity is designed and fabricated for experimental study. In the two experiments, the effectiveness of the proposed quasi-zero stiffness mechanism used in the field of constant-force output and vibration isolation is tested.

Exoskeletons can track the wearer’s movements in real time, thereby enhancing physical performance or restoring mobility for individuals with gait impairments. These wearable assistive devices have demonstrated significant potential in both rehabilitation and industrial applications. This review focuses on the major advancements in exoskeleton technology published since 2020, with particular emphasis on the development of structural designs for lower-limb exoskeletons employed in locomotion assistance. We employed a systematic literature review methodology, categorizing the included studies into three main types: rigid exoskeleton, soft exoskeleton, and tethered platform. The current development status of robotic exoskeletons is analyzed based on publication year, system weight, target assistive joints, and main effects. Furthermore, we examine the factors driving these advancements and their implications for the field. The key challenges and opportunities that may influence the future development of exoskeleton technologies are also highlighted in this review.