Real-Time Foot Tracking and Gait Evaluation with Geometric Modeling.

Gait evaluation is important in gait rehabilitation and assistance to monitor patient's balance status and assess recovery performance. Recent technologies leverage on vision-based systems with high portability and low operational complexity. In this paper, we propose a new vision-based foot tracking algorithm specially catering to overground gait assistive devices, which often have limited view of the users. The algorithm models the foot and the shank of the user using simple geometry. Through cost optimization, it then aligns the models to the point cloud, showing the back view of the user's lower limbs. The system outputs the poses of the feet, which are used to compute the spatial-temporal gait parameters. Seven healthy young subjects are recruited to perform overground and treadmill walking trials. The results of the algorithm are compared with the motion capture system and a third-party gait analysis software. The algorithm has a fitting rotational and translational errors of less than 20 degrees and 33 mm, respectively, for 0.4 m/s walking speed. The gait detection F1 score achieves more than 96.8%. The step length and step width errors are around 35 mm, while the cycle time error is less than 38 ms. The proposed algorithm provides a fast, contactless, portable, and cost-effective gait evaluation method without requiring the user to wear any customized footwear.

Development and Evaluation of a Novel Passive Wrist Bilateral Rehabilitation Device paired with Virtual Reality: A Feasibility Study.

This paper introduces a novel passive wrist bilateral rehabilitation device coupled with a new Virtual Reality (VR) platform. This is the first work to have adapted three-link coaxial spherical parallel manipulator (SPM) to wrist rehabilitation. The device comprises a coaxial SPM and cross-connected cable system. The coaxial SPM facilitates 3 degrees of freedom (DOFs) spherical wrist orientation and singularity-free motion within its workspace. The cross-connected cable system enables bilateral symmetrical exercises in passive mode training. A VR platform with activities of daily living (ADL) task was developed and coupled with the device to increase the adherence of the users to the device. Experiments were conducted with fifteen healthy right-handed individuals with no history of wrist or hand injury to evaluate the feasibility of the system for providing passive bilateral training as well as the effectiveness of the VR platform. Subjects were asked to use their right arms to move the left arms passively through the device to perform four wrist movements, flexion, extension, radial deviation, and ulnar deviation. EMG activations on the left arm were observed when the right arm passively moved the left arm. The results showed that the device was capable of inducing the muscle activation of the left arm and the VR platform increased the motivation to continue the exercises. This demonstrates that this study can serve as the fundamental for larger clinical trials.