Gait Analysis Using Wearable Sensors

Gait analysis using wearable sensors is an inexpensive, convenient, and efficient manner of providing useful information for multiple health-related applications. As a clinical tool applied in the rehabilitation and diagnosis of medical conditions and sport activities, gait analysis using wearable sensors shows great prospects. The current paper reviews available wearable sensors and ambulatory gait analysis methods based on the various wearable sensors. After an introduction of the gait phases, the principles and features of wearable sensors used in gait analysis are provided. The gait analysis methods based on wearable sensors is divided into gait kinematics, gait kinetics, and electromyography. Studies on the current methods are reviewed, and applications in sports, rehabilitation, and clinical diagnosis are summarized separately. With the development of sensor technology and the analysis method, gait analysis using wearable sensors is expected to play an increasingly important role in clinical applications

Research on Dynamics and Stability in the Stairs-Climbing of a Tracked Mobile Robot

Aiming at the functional requirement of climbing up the stairs, the dynamics and stability during a tracked mobile robot's climbing of stairs is studied. First, from the analysis of its cross-country performance, the mechanical structure of the tracked mobile robot is designed and the hardware composition of its control system is given. Second, based on the analysis to its stairs-climbing process, the dynamical model of stairs-climbing is established by using the classical mechanics method. Next, the stability conditions for its stairs-climbing are determined and an evaluation method of its stairs-climbing stability is proposed, based on a mechanics analysis on the robot's backwards tumbling during the stairs-climbing process. Through simulation and experiments, the effectiveness of the dynamical model and the stability evaluation method of the tracked mobile robot in stairs-climbing is verified, which can provide design and analysis foundations for the tracked mobile robots' stairs-climbing

Small-Sample Accelerated Life Test Method based on the Inverse Power Law Model

To obtain the characteristic life of a chain tool magazine and automatic tool changer under normal working condition, a small-sample accelerated life test method was developed. The inverse power law model and small-sample virtual augmented theory was applied while taking vibration as the accelerated stress. The accelerated life test of the automatic tool changer was carried out under different stress levels. The results showed that the “Mean Cycles between Failures” of exchanging tool under normal stress was about 28283 times for the chain tool magazine and automatic tool changer. The proposed small-sample accelerated life test method, which based on the inverse power law model, could also be used in other relevant large-scale and complex products

Small-Sample Accelerated Life Test Method based on the Inverse Power Law Model

Abstract: To obtain the characteristic life of a chain tool magazine and automatic tool changer under normal working condition, a small-sample accelerated life test method was developed. The inverse power law model and small-sample virtual augmented theory was applied while taking vibration as the accelerated stress. The accelerated life test of the automatic tool changer was carried out under different stress levels. The results showed that the “Mean Cycles between Failures ” of exchanging tool under normal stress was about 28283 times for the chain tool magazine and automatic tool changer. The proposed small-sample accelerated life test method, which based on the inverse power law model, could also be used in other relevant large-scale and complex products