A Bionic Test-Bed for Sensing and Balance Augmentation in Biological Applications

Abstract

In this research, we are working to develop a wearable device for stabilizing walking in dachshunds with spinal cord injuries. Our approach is to use sensors on the dog to measure the angle of the torso and stimulate leg motion to balance the animal during standing and walking. The first step in this work is to develop a mechanical test-bed in order to replicate the motion and muscle response during the gait of the dog. This testbed will be used for exploring sensor device operation and for developing appropriate leg stimulation to achieve stability. This robotic testbed is a replica of dog’s rear limbs and is programmed to mimic the gait of the dog. Our initial experiments test the automatic stabilization of the robot by mimicking the walking gait of a healthy dog. We use test data from an actual dog walking on a treadmill to develop representative walking gait characteristics for use on our experimental test bed. Our results show that our bionic dog is an acceptable replica for use in testing the stabilization and control algorithms.

A Wearable Body Controlling Device for Application of Functional Electrical Stimulation

“…The trajectory of the normal walking gait for typical dog have been previously studied [ 39 ] in order to identify the hip, knee and hock angles during walking. VICON [ 44 ] video tracking software was used to record the motion of markers attached to the hock, knee, and hip joint of an adult dog while walking normally on a treadmill at a speed of 5 km/h.…”

“…In previous work [ 39 ], an earlier version of the test-bed was developed with a single motorized axis, based of veterinarian experience that the hock joint was used by dogs as the primary balancing joint. This work demonstrated the efficacy of using the bionic test bed for development, but also pointed to the need for a more complete hindquarters model of the dog.…”

A Neuro-Prosthetic Device for Substituting Sensory Functions during Stance Phase of the Gait

“…In our previous work [17], we designed and built a FES-based wearable device using an Arduino Uno board that could be used for stimulation of hindleg muscles of dogs suffering from spinal cord injury. The sensing core of this balancing device includes a single IMU attached to the pelvis of the dog to gain data about pelvis angle of rotation.…”

“…In our previous study [17], we showed VICON software could be used to obtain various data about animal gait including changes in animal joint angles during each step. We used Fourier series to approximate VICON discrete time data about joint angles as continuous time functions.…”

“…The block diagram for each motor-potentiometer joint controlling has been shown in Figure 7. The gait motion for each leg follows the average, representative, open loop gait based on approximated functions of joints angles found in our previous studies [17]. The legs follow the predetermined gait trajectories, but, for mimicking falling, we used the same controlling strategy for the left limb and with a separate Teensy that calculates the desired joints angles based on a modified falling function.…”