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For individuals with movement impairments due to neurological injuries, rehabilitative therapies such as functional electrical stimulation (FES) and rehabilitation robots hold vast potential to improve their mobility and activities of daily living. Combining FES with rehabilitation robots results in intimately coordinated human–robot interaction. An example of such interaction is FES cycling, where motorized assistance can provide high-intensity and repetitive practice of coordinated limb motion, resulting in physiological and functional benefits. In this paper, the development of multiple FES cycling testbeds and safeguards is described, along with the switched nonlinear dynamics of the cycle–rider system. Closed-loop FES cycling control designs are described for cadence and torque tracking. For each tracking objective, the authors’ past work on robust and adaptive controllers used to compute muscle stimulation and motor current inputs is presented and discussed. Experimental results involving both able-bodied individuals and participants with neurological injuries are provided for each combination of controller and tracking objective. Trade-offs for the control algorithms are discussed based on the requirements for implementation, desired rehabilitation outcomes and resulting rider performance. Lastly, future works and the applicability of the developed methods to additional technologies including teleoperated robotics are outlined. 

Recent advances in robotics have accelerated their widespread use in nontraditional domains such as law enforcement. The inclusion of robotics allows for the introduction of time and space in dangerous situations, and protects law enforcement officers (LEOs) from the many potentially dangerous situations they encounter. In this paper, a teleoperated robot prototype was designed and tested to allow LEOs to remotely and transparently communicate and interact with others. The robot featured near face-to-face interactivity and accuracy across multiple verbal and non-verbal modes using screens, microphones, and speakers. In cooperation with multiple law enforcement agencies, results are presented on this dynamic and integrative teleoperated communicative robot platform in terms of attitudes towards robots, trust in robot operation, and trust in human-robot-human interaction and communication. 

A wide variation in muscle strength and asymmetry exists in people with movement disorders. Functional electrical stimulation (FES) can be used to induce muscle contractions to assist and a motor can be used to both assist and resist a person’s volitional and/or FES-induced pedaling. On a traditional cycle with coupled pedals, people with neuromuscular asymmetries can primarily use their dominant (i.e., stronger) side to successfully pedal at a desired cadence, neglecting the side that would benefit most from rehabilitation. In this paper, a multi-level switched system is applied to a two-sided control objective to maintain a desired range of cadence using FES, an electric motor, and volitional pedaling. The non-dominant leg tracks the cadence range while the dominant leg tracks the position (offset by 180 degrees) and cadence of the first leg. Assistive, uncontrolled, and resistive modes are developed based on cadence and position for the non-dominant and dominant legs, respectively. Lyapunov-based methods for switched systems are used to prove global exponential tracking to the desired cadence range for the combined FES-motor control system.