ROCR is an oscillating climbing robot: Dynamically climbing sheer walls with a pendular two-link mass-shifting robot

Driven by the need for lightweight, energy efficient, mission adaptable climbing robots, a new type of vertical wall climbing robot is developed. This thesis presents a novel bio-inspired dynamic climbing robot, with a recursive name: ROCR is an Oscillating Climbing Robot. ROCR is a pendular two-link, serial chain robot that utilizes alternating hand-holds and an actuated tail to propel itself upward in a climbing style based on observation of human climbers and brachiating gibbons. ROCR's bio-inspired oscillating climbing strategy is simple and efficient. ROCR's physical, electrical and software design are flexible and robust, opening up the option of using ROCR in a wide range of environments and enabling ROCR to perform a variety of tasks. This robot is intended for autonomous surveillance and inspection on sheer vertical surfaces. Potential locomotion gait strategies were investigated in simulation using Working Model 2D and Matlab. Climbing gait strategy comparisons were drawn on the basis of climbing rate and energy efficiency. Simulation results show the feasibility and relative merits of these climbing gait strategies and compare them to the potential energy gained while climbing. A first generation ROCR design, having physical parameters based on simulation analysis, that utilizes actuated permanent magnet grippers and a geared-motor actuated tail was fabricated. Several generations of ROCR were subsequently designed, fabricated and tested as the climbing strategy and design parameters were refined through testing and simulation. Magnetic grippers were used for the initial prototypes to facilitate investigating the robot's climbing efficiency. Subsequent prototypes utilized hooks to climb carpeted vertical surfaces. Several climbing gaits which showed promise in simulation were implemented in the prototypes and compared experimentally. ROCR is a lightweight, flexible, self-contained robot with on-board microcontroller, tilt and acceleration sensing, voltage regulator, batteries and wireless communication. This robot shows very promising results in terms of energy efficient dynamic climbing on a variety of vertical surfaces.