Unlike earlier generations of medical exoskeletons, which typically require crutches or a walker and rely on pre-programmed, rigid gait patterns, self-balancing designs aim to keep the user upright dynamically, allowing more natural overground movement. That added freedom, however, introduces new engineering challenges: the control system must continuously stabilize the body without the external support of walking aids, and the user must trust that the machine will not tip. Before any device of this kind can move toward clinical deployment, its developers must rigorously assess usability, operational reliability, and safety — which is precisely what this study set out to do.

The evaluation was deliberately structured to capture the experience of both sides of the human-machine partnership: the device users and the trained operators who supervise them. Three adult participants with chronic motor-complete spinal cord injury, with neurological injury levels between T3 and T10 and ASIA Impairment Scale grades A to B, took part in twelve sessions over a four-week period. Six operators, all members of the research team, completed parallel assessments. The protocol unfolded across three distinct phases designed to mirror how a real clinical introduction of the technology might proceed.

In the first phase, participants underwent screening and intake, including anthropometric evaluations and familiarization with the device through a simulator. The second phase focused on physical preparation: fitting the exoskeleton, practicing the donning and doffing procedures, and collecting baseline performance measurements. Only in the third phase did participants begin true intervention exposure, progressing through sit-to-stand movements, overground walking, and tasks drawn from the Functional Gait Assessment, a standardized clinical measure of walking ability. This phased design allowed the researchers to observe how users and operators adapted to the technology incrementally, while documenting every friction point along the way.

Feedback was collected through structured, self-administered questionnaires. Participants rated ease of use, user confidence, and system design, while operators provided their own ratings covering setup workflow, device control, and perceived stability. The results painted a cautiously encouraging picture. Participants reported high usability overall, particularly praising the ease of system setup and expressing strong confidence in the device. Operators rated usability as moderate, reflecting genuine enthusiasm for the device’s rehabilitation potential tempered by real-world difficulties during early familiarization.

Those difficulties are exactly the kind of granular data that beta-stage testing exists to capture. Participants identified several areas needing improvement: the process of transferring onto the device before donning it, the clarity of the device’s messaging on its displays, and the smoothness of movement transitions between different activities. Operators, meanwhile, flagged challenges in device setup, the responsiveness of the joystick controller, and their perception of system stability during early sessions. None of these findings invalidates the technology; rather, they map out the engineering and training priorities that must be resolved before the device can safely leave the laboratory.

The safety findings deserve particular attention, because they illustrate the complexity of deploying powered mobility devices in a population with sensory and motor impairment. Adverse events recorded during the study included skin irritation and bruising — known risks for exoskeleton users, whose insensate skin endures direct mechanical loading from rigid braces and straps. More seriously, one participant sustained a tibial fracture during a sit-to-stand-to-sit transfer. The post-event review concluded that contributing factors were multifactorial and did not identify a confirmed device malfunction. Bone health is a critical concern in chronic spinal cord injury, as prolonged immobilization leads to significant loss of bone mineral density, making even routine transfers a potential fracture risk. This single event underscores why the study’s authors argue that future work must embrace multifactorial risk-mitigation strategies that account for participant-specific factors, training and setup conditions, and device operation as an integrated whole.

The study’s conclusions are measured but optimistic. The Beta 2 investigational prototype demonstrated positive usability from users and showed potential to support rehabilitation-related activities according to operators. The authors recommend that future development focus on improving system responsiveness and operator workflow, alongside the broader risk-mitigation framework. Notably, the manuscript also includes a brief manufacturer commentary contextualizing how the device has evolved, a transparency gesture that reflects the collaborative nature of the project, which was supported by Team I WILL and the UHN Foundation, with equipment and technical support from Human in Motion Robotics under an Innovation Solutions Canada grant.

What makes this pilot study significant beyond its small sample is its methodological honesty. Usability research in rehabilitation robotics often emphasizes performance metrics — walking speed, distance, physiological outcomes — while giving less attention to the lived experience of the humans strapped into the machine. By systematically collecting feedback from both users and operators across a phased protocol, the research team has produced a template for how investigational devices should be evaluated before clinical deployment. The study also acknowledges the people who made it possible: the device users who, as the authors write, bravely participated in this phase I trial and materially contributed to the usability assessment.

The road from investigational prototype to clinically available device remains long, and this study’s findings — from joystick responsiveness to fracture risk during transfers — will feed directly into the next iteration of the technology. But the core message is one of momentum. A self-balancing exoskeleton that users found easy to set up and confidence-inspiring, that operators judged capable of supporting rehabilitation goals, and whose safety profile could be characterized and understood in detail, represents a meaningful step toward a future in which standing and walking are realistic options for people living with paralysis. As self-balancing robotic gait technology continues to mature, studies like this one will define the standards by which the field earns the trust of its users.

Subject of Research: Usability and safety evaluation of a self-balancing overground exoskeleton for adults with chronic motor-complete spinal cord injury

Article Title: Pilot usability and participant experience evaluation with an investigational self-balancing overground exoskeleton in adult users with chronic motor-complete paraplegia

Article References: Tsang, P., Souza, W. H., Walden, T. P., Park, E. J., Arzanpour, S., Dehghani, H., Peykari, B., & Craven, B. C. (2026). Pilot usability and participant experience evaluation with an investigational self-balancing overground exoskeleton in adult users with chronic motor-complete paraplegia. BioMedical Engineering OnLine. https://doi.org/10.1186/s12938-026-01623-5

Image Credits: AI Generated

DOI: 10.1186/s12938-026-01623-5

Keywords: spinal cord injury, exoskeleton, self-balancing robotics, usability, rehabilitation robotics, overground walking, paraplegia, adverse events, functional gait assessment, wearable technology, pilot study, assistive technology