The upper limb exoskeletons is an innovative electromechanical, robotic system wearable dedicated to enhancing user's upper limb physical movement or provide upper body assistance in rehabilitation. Within the United States, an estimation of 17,900 new spinal cord injury (SCI) cases occurs each year. According to the National Spinal Cord Injury Statistical Center (NSCISC), 38.2 percent of SCI is caused by vehicle crashes since 2015. People with SCI often need significant assistance to carry out their daily activities and may severely impact their quality of life. Therefore, the research and developments in upper limb exoskeleton are becoming another important innovation in the field of medical robotics.

The projects presented in this section plays a role in contributing to the field of human-robot interaction and assistive technology, and will serve as a foundation for future innovation. 

A lightweight and adjustable upper limb exoskeleton has been designed and developed to assist individuals with mobility impairments resulting from spinal injuries or strokes. This exoskeleton offers mobility assistance for elbow and shoulder movements, addressing the rehabilitation needs of patients.

The design is focused on being lightweight, adjustable, affordable, and suitable for individuals of varying body types. Each joint is designed as an adjustable revolute joint providing a full range of motion with a single actuated degree of freedom (DOF). The arm of the exoskeleton is designed as a prismatic joint to allow length adjustment of each link. Motors are situated on the body and actuate each joint with Bowden cables and pulleys. The mechatronic system utilizes an ESP32 microcontroller, a T-motor AK80-9 motor, and an MPU 6050 accelerometer sensor. The motors use CAN communication with minimal communication latency that provides efficient real-time movements of the motor. The backpack-style design reduces the device's overall size and weight.

Materials used to manufacture the components were polyethylene terephthalate glycol (PETG) and thermoplastic polyurethane (TPU) with the FDM 3D printing method. Steel and aluminum materials were used for the pulley shafts and outer links. Carbon Fiber and High-density Polyethylene (HDPE) components are utilized in high-stress areas.

The upper limb exoskeleton offers an effective and affordable solution for rehabilitation in cases of spinal cord injuries and post-stroke conditions. It provides mobility assistance across all ranges of motion, accelerating recovery and improving the quality of life for users.

Team members: Nathanael Lacuata, Brandon O'dell, Anthony John

For this lightweight upper limb exoskeleton, a semi-rigid chain has been designed to address the misalignment issue of the body joint movements. The joints were adapted to the motors that are situated on the body, actuating joints with Bowden cables and pulleys. The degrees of freedom (DOFs) are abduction-adduction and flexion-extension of the shoulder and flexion-extension of the elbow. 

Based on the FEA analysis performed, the chosen material used for the semi-rigid chain design was carbon fiber-infused polyethylene terephthalate glycol (PETG-CF) for critical components and thermoplastic polyurethane (TPU) for areas interacting with the user that requires a flexible material for comfort. The parts were manufactured using the FDM 3D printing method.

The cable-driven upper limb exoskeleton provides an alternative actuation method as a proof-of-concept that can be further developed to provide a lighter-weight exoskeleton used for human assistance in various strenuous tasks or for rehabilitation purposes.

Team member: Yu Xian Lim

A new hand exoskeleton prototype is designed and developed in this project, representing an assistive device for post-stroke patients and individuals requiring hand rehabilitation. Flex sensors were integrated into a soft glove, enabling precise and intuitive control of the exoskeleton in response to natural finger movements. This user-friendly and patient-centric mechanism ensures a wide range of motion to mirror the exact movements of the user's opposite hand or the therapist's hand. This has the potential to enhance the effectiveness of assistance and rehabilitation strategies. Current progress is underway to improve the hand exoskeleton with a synergy-based mechanical design to move finger groups with less number of actuators.

Team member: Yoseph Chaka, Perla Portillo, Ezekiel John Saldajeno, Rubin Gonsalves