Dongjun Shin

Developing a robotic hand that integrates high fingertip force, rapid response, and multi-degree-of-freedom (DoF) motion to achieve human hand-like capabilities remains a challenge in the field of robotic hands. This study presents the SOFRo Gripper, a soft, high-force robotic gripper designed to combine these capabilities within a compact pneumatic architecture. The finger module of the SOFRo gripper incorporates synergistically arranged chambers together with a multinode tendon routing strategy that distributes actuation forces, enabling both flexion and abduction/adduction motions while enhancing fingertip force. Furthermore, a Force-Enhanced Pleated (FEP) mechanism was applied to the chambers to increase fingertip force, resulting in a 32.41% improvement over conventional chamber designs. The proposed SOFRo gripper achieves a high fingertip force of 68.76 N and dexterous motion capabilities, enabling a maximum lifting force of 400.0 N and in-hand manipulation. To validate its versatility, extensive experiments were conducted across a wide range of tasks, including object grasping, high-force manipulation (e.g., lifting heavy objects, closing a valve), delicate handling (e.g., grasping tofu, inserting a light bulb), and high-speed manipulation (e.g., spinning a top, catching a ball). These results demonstrate the SOFRo Gripper’s ability to combine high force with versatile soft robotic manipulation.

Team BeAGain’s development of the whole-body FES robotic bicycle and triumph at Cybathlon 2024 are presented.

Soft wearable robots have gained widespread interest across various disciplines; however, they remain insufficient in overcoming the physical limitations of the human body. In particular, enhancing vertical jump height, a commonly used indicator of physical capability, requires improved actuator power density, stroke length, and soft structure efficiency. To address these challenges, the Jump‐Enhancing Textile Suit is proposed, which integrates the Pneumatic Energy‐Storing Propulsion Actuator (PESPA) and the Triarticular Kinetic‐Chained Structure (TKiCS) to assist jump performance. PESPA stores elastic energy under pneumatic pressure and releases it during the propulsive phase to augment human movement. TKiCS uses the kinetic chain mechanism to reduce anchoring points and fully harness the high stiffness region, thereby improving force transmission efficiency. Controlled vertical jump experiments with healthy adult participants are conducted. The suit increases jump height by 3.74 cm on average and up to 9.04 cm maximum, while also enhancing hip, knee, and ankle torques. Under isotonic testing, PESPA achieves a power density of 2298.69 W kg ⁻¹ and outperforms conventional pneumatic actuators. A dynamic model enables accurate force prediction and precise timing for effective assistance. These findings establish a practical foundation for pneumatic wearable robotics and suggest applications in jump augmentation, rehabilitation, and athletic performance.

A manual handling task is one of the most common causes of back injuries, accounting for nearly 31.9% of the total work‐related injuries. To promote a safe working environment for workers, wearable robots (wearables) are rapidly emerging to fulfill various needs in human‐robot interactive tasks. Although numerous studies have successfully developed wearables to assist humans, they are often limited to supporting a single degree of freedom (DoF) of the human body with a single actuator. However, as humans tend to use multiple parts of their bodies, additional actuators and mechanisms to transmit force/motion are necessary to realize multi‐DoF, which increases the volume, price, and complexity of the wearables. To address these issues, a multi‐DoF wearable robot (WeaRo) with an adjustable twisted string actuator (ATSA) and a two‐stage transmission mechanism (2TM) is proposed. By introducing the novel ATSA and 2TM, the proposed WeaRo achieves multi‐DoF (lumbar and arm) with only a single electric motor and ATSA. Experimental results demonstrate that the proposed WeaRo effectively reduces the maximal voluntary contraction (%MVC) of lumbar, biceps, and triceps muscles by a maximum of 18.2, 29.1, and 27.0%, respectively without constraining users’ movements. Additionally, the fabric‐based design ensures a lightweight solution weighing 5.2 kg including batteries.

We developed flexible, lightweight, and washable gloves with actuators to assist finger movements and improve ease of wearing. Performance and wearability were measured using standardized tests, triangulation of bending angles, electromyography (EMG), and grip strength. User satisfaction was measured using a survey. EMG sensors were attached to the flexor digitorum superficialis and extensor digitorum communis to capture movement data for grasping and releasing, lifting and putting down, and opening and closing an object with (a) gloves and an actuator, (b) gloves and no actuator, and (c) no gloves. The actuator-equipped glove weighed 31.4 g—lighter than in any earlier studies. In situation (a), the average EMG values for the four participants decreased, ranging from −2.06% to −44.1%, confirming the superior performance of the gloves. Survey results revealed high levels of user satisfaction. Our study offers insights into the development of rehabilitation robotic gloves that assist muscle movements and are easy to wear.

Pneumatic artificial muscles (PAMs) have shown promising potential as actuators for safe human–robot interaction due to their high force density and inherent compliance. However, drawbacks such as force reduction, relatively poor control performance, and low energy efficiency have hindered the practical application of PAMs for robotic systems. Although various approaches were conducted to enhance the applicability of PAMs, there is still a lack of research on effective transmission mechanisms that can fully exploit the actuation characteristics of PAMs. In this article, we propose a patella-inspired linkage joint (PatLink) to address the tradeoff problem between torque and speed in conventional mechanisms with PAMs. The proposed mechanism amplifies the joint rotation angle with respect to the muscle contraction length, thereby increasing the joint angular velocity. Furthermore, the PatLink enables the PAMs’ actuation force to be utilized over a wider range of joint angles, further improving the torque output. Experimental results showed 103% increase in range of motion and 106% enhancement in mean work rate under the same input, thereby validating the effectiveness of the PatLink. The proposed mechanism can be further expanded to various contraction-type soft actuators, such as shape memory alloy actuators and twisted string actuators, which possess similar force characteristics to PAMs.

A lumbar-degenerative flat back is a condition caused by a decline in back muscle strength with aging. The symptoms of this condition include severe lower back pain and spinal disorders, which restrict people from performing activities of daily living (ADL). Recently, various wearable robots have been developed to assist the weakened muscles. However, despite their effectiveness, the wearables require either bulky and rigid structures (active wearables) or tend to constrain users’ motion (passive wearables). In addition, the complex biomechanics of the human spine have not been sufficiently investigated during the design process. To address these issues, we propose a human-inspired spine assistive robot with a routed twisted string actuator (RTSA, active element) and a flat-back alleviation mechanism (FAM, passive element). This innovative RTSA conforms to the complex human spine curvature while minimizing friction and assists the ADL with its unique prioritizing characteristics. The human spine-inspired FAM, on the other hand, was designed to prevent spinal disorder injury while performing ADL. The experimental results showed that the proposed system successfully reduced the electromyography signals while performing ADL. Furthermore, the spinal disorder injury during trunk motion could be prevented by reducing the lumbopelvic ratio of the users.

With the ongoing research on soft robots, the performance of soft actuators needs to be enhanced for more wide robotic applications. Currently, most soft robots based on pneumatic actuation are capable of assisting small systems, but they are not fully suited for supporting joints requiring large force and range of motion. This is due to the actuation characteristics of the pneumatic artificial muscle (PAM); they are relatively slow, inefficient, and experience a significant force reduction when the PAM contracts. Hence, we propose a novel PAM based on a spring-frame collateral compression mechanism. With only a single compressed air source, the external mesh-covered and inner spring-frame actuators of the proposed PAM operate simultaneously to generate considerable force. Additionally, the design of the internal actuator within the void space of PAM reduces the air consumption and consequently improves the actuator’s operating speed and efficiency. We experimentally confirmed that the proposed PAM exhibited 31.2% greater force, was 25.6% faster, and consumed 21.5% lower air compared to the conventional McKibben muscles. The performance enhancement of the proposed PAM improves the performance of soft robots, allowing the development of more compact robots with greater assistive range.