This Study Evaluates the Use of a Data-driven Lower Limb Exoskeleton Controller for Stroke Rehabilitation.

Official title

From Stroke Rehabilitation to Independence: An Impairment-Aware Control Framework for Adaptive Exoskeleton Assistance

Overview

The goal of this clinical trial is to test a new, impairment-aware robotic control software framework to see if its smart adaptation can improve walking recovery in healthy adults and chronic stroke survivors. . The main questions it aims to answer are: Can the new control software safely use sensors and machine learning to predict and instantly adapt to a user's specific walking needs? Does training with a robotic device driven by this new adaptive control framework improve walking speed and overall mobility in stroke survivors? Researchers will compare a lower-limb orthosis operating under the new "smart" control software (which adapts to the user's impairment) to the same device operating under a standard, non-adaptive controller (which uses rigid or fixed assistance) to see if the new control approach leads to greater improvements in walking ability. Participants will: Walk on treadmills, flat walkways, or stairs while wearing a robotic leg orthosis driven by the different control software systems being tested. Wear small tracking tools (like reflective motion-capture markers and muscle activity sensors) so researchers can precisely measure how their movements interact with each control program. Complete standard walking tests to measure their walking speed and overall mobility under each software condition.

Interventions

• Device Unified Control Framework for Lower-Limb Powered Orthosis
  An AI-driven, machine learning-based control software integrated into a wearable lower-limb powered orthosis. The system utilizes a Bayesian Neural Network (BNN) to analyze a user's pathological walking patterns (kinematics) in real-time via onboard sensors. Based on this real-time performance, the device dynamically modulates its physical assistance along a seamless continuum. It automatically transitions between stiff corrective guidance (position-based gait training) when the user struggles,
• Device Conventional Robotic Controller
  A standard control paradigm for lower-limb powered orthoses that provides non-adaptive physical assistance during gait training. Depending on the trial block, the device operates in one of two static modalities: either rigid position-based gait training (GT) that physically guides the patient's limbs through a fixed, predetermined trajectory regardless of effort, or torque-based volitional augmentation (VA) that proportionally amplifies existing muscle output or ground reaction forces. Unlike th

Primary outcome measures

• Walking Speed [Time frame: Baseline (Week 0), Post-Intervention Phase 1 (Week 4), Post-Washout / Pre-Intervention Phase 2 (Week 8), and Post-Intervention Phase 2 (Week 12).]
• Functional Mobility and Balance [Time frame: Baseline (Week 0), Post-Intervention Phase 1 (Week 4), Post-Washout / Pre-Intervention Phase 2 (Week 8), and Post-Intervention Phase 2 (Week 12).]

Secondary outcome measures (3)

• Acute Within-Session Changes in Spatial Gait Symmetry [Time frame: Baseline (Week 0) and weekly during the 12 training sessions across each 4-week intervention period.]
• Acute Within-Session Changes in Ground Reaction Force Symmetry [Time frame: Baseline (Week 0) and weekly during the 12 training sessions across each 4-week intervention period.]
• Acute Within-Session Changes in Joint Range of Motion [Time frame: Baseline (Week 0) and weekly during the 12 training sessions across each 4-week intervention period.]

Eligibility criteria

Inclusion criteria

• Cohort 1: Able-Bodied Participants (Initial Validation)
• Healthy young adults.
• No history of neurological, orthopedic, or cardiovascular impairments affecting gait or balance.
• Able to walk independently without assistive devices.

Cohort 2: Stroke Survivors (Clinical Efficacy Pilot)

• Individuals with a documented history of chronic stroke.
• Persistent unilateral lower-limb motor impairment resulting in a pathological gait pattern (heterogeneous gait deficits).
• Stable medical condition allowing for participation in intensive physical rehabilitation tasks.
• Able to provide informed consent.

Exclusion criteria

• Severe cognitive or communication impairments that prevent the participant from following safety instructions or reporting discomfort.
• Co-existing neurological conditions (other than stroke) that independently impair locomotion (e.g., Parkinson's disease, Multiple Sclerosis).
• Severe lower-limb joint contractures or orthopedic conditions that mechanically restrict the safe range of motion of the robotic orthosis.
• Skin breakdowns, open wounds, or severe unhealed lesions at the contact points where the powered orthosis interfaces with the lower limbs.
• Any medical contraindication to intensive walking exercise or treadmill training (e.g., unstable angina, severe unmanaged cardiovascular disease).

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: Yes

Study design

Allocation

Randomized

Model

Crossover

Masking

Open label

Primary purpose

Treatment

Study locations

United States · 1 center

• Rehabilitation Laboratory in the Ford Robotics Building on the University of Michigan Nort — Ann Arbor

Identifiers

NCT: NCT07616167 · HUM00287262

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗