Multi-Robot Cyber-Physical System For Assisting Young Developmentally-Delayed Children in Learning to Walk

This project is a modular, computationally-distributed multi-robot cyberphysical system (CPS) for assisting young developmentally-delayed children in learning to walk. Three challenges are stabilizing medio-lateral body sway, developing gait that exploits energy exchange, and coordination of multiple degrees of freedom. Adults assisting children learning to walk provide a "scaffold" of postural supports that enables the child to safely explore the forces acting on its body. In order to capture the adaptability of the adult in responding to the child's learning, our CPS consists of 1) a scaffold that modulates and stabilizes center of mass sway, and 2) a soft, wearable exosuit with embedded sensing and actuation to assist walking. The aims are:

• To measure kinematics, kinetics, and center of mass (COM) behavior at hip, knee, and ankle during standing and walking
• Lower body toddler model for bench top testing
• Joint actuator/suit design and testing
• Scaffold design and testing
• Adult-toddler interaction biomechanics
• Gloves, design
• Gloves, data
• Study procedures

We present preliminary data from a typically developing toddler with three months of walking experience. These data are used to inform joint actuation, suit design, and scaffold design in order to provide appropriate kinematic/kinetic inputs to assist with joint motion and center of mass behavior. We also present a toddler leg model designed to be used for benchtop testing of both the actuated exosuit as well as the scaffold design. The model has the same proportions and has the same range of motion as a young toddler's legs. This is critical to ensuring that any system designed and tested on the model will be given accurate feedback. The main task of the exosuit is to actuate the toddler limbs and maintain whole limb behavior in coordination with the scaffold's manipulation of the toddler center of mass. Pneumatic artificial muscles were chosen for the actuators because they are lightweight and generate the correct range of forces. Actuators were mounted on a suit consisting of a two-part sleeve around the trunk-pelvis, as well as around the middle of each thigh. The goal of studying adult-child interactive forces is to measure and analyze the forces adults apply to children who are learning to walk in order to stabilize them and assist with forward movement. To facilitate these studies, we have developed instrumented glove hardware which can be used to measure these