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In this study, we present the experimental results demonstrating the functionality of our recently developed "balancing device" for walking restoration in patients with spinal cord injuries. Since we are preparing this device for testing on dogs, we program the analytical core of the device to recognize both stance and swing phases of the dog gait, the direction that the dog is falling, as well as selecting a suitable balancing strategy to prevent falling. The analytical core of the device is a commercial microcontroller, the Teensy, which is able to provide suitable stimulation commands and intensities as a voltage for delivery to the stimulation circuit and target muscles. We show the functional schematic of the device along with experimental results obtained by testing the device in a simulated robotic dog. Results show that the sensory system of the animal lost by spinal cord injury can be replaced by the sensing core of the device and the analytical core can provide appropriate stimulation control to balance the body of a dog. All test results are obtained using our robot test-bed and living animals are not involved in this study. [ABSTRACT FROM AUTHOR]

In this research, we describe a new balancing device used to stabilize the rear quarters of a patient dog with spinal cord injuries. Our approach uses inertial measurement sensing and direct leg actuation to lay a foundation for eventual muscle control by means of direct functional electrical stimulation (FES). During this phase of development, we designed and built a mechanical test-bed to develop the control and stimulation algorithms before we use the device on our animal subjects. We designed the bionic test-bed to mimic the typical walking gait of a dog and use it to develop and test the functionality of the balancing device for stabilization of patient dogs with hindquarter paralysis. We present analysis for various muscle stimulation and balancing strategies, and our device can be used by veterinarians to tailor the stimulation strength and temporal distribution for any individual patient dog. We develop stabilizing muscle stimulation strategies using the robotic test-bed to enhance walking stability. We present experimental results using the bionic test-bed to demonstrate that the balancing device can provide an effective sensing strategy and deliver the required motion control commands for stabilizing an actual dog with a spinal cord injury. [ABSTRACT FROM AUTHOR]

Haptic interactions have become increasingly important as an interface to computer-generated simulations in virtual-reality (VR) applications. Many haptic devices are designed to be used as a force feedback mouse, where the user's hand is in contact with the haptic device while the object contact and force generation occur on a computer screen. In this paper, we present an approach using a “virtual probe” to interact with the environment and introduce a new method to generate impedance-based haptic forces based on the use of a virtual manipulator. The virtual probe is connected directly to the haptic device and is projected from the hand to the environment, much like a scalpel or sword. As the probe comes in contact with the environment, the haptic device generates appropriate forces on the hand. We extend this approach to include underactuated haptic devices, which do not have fully powered joints. We show that the approach compensates for missing joint actuation in the underactuated haptic devices. We show experimental results for a simple case of haptic interaction; we also present an experimental implementation in six degrees of freedom (DOF) using one of the most popular devices: the PHANTOM. [ABSTRACT FROM AUTHOR]