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Modeling, Analysis, and Controllability of a Single-Actuator Differentially-Driven Robot


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In this paper, we develop an elaborate three-dimensional dynamical model for a novel single-actuator variable-diameter differentially-driven robot by taking recourse to Lagrangian formulation. Utilizing this model, we were able to analyze the various parameters and develop design tools that could be used in realizing such a robot with certain motion requirements. Given the single actuator design that inherently limits steering, the proposed model is an excellent platform to test optimal path planning techniques such as Dubins curves. We study the effect of dynamical forces on following time-optimal trajectories and finally we analyze the controllability of our system.
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... His design, seen in Fig.1, includes flexible wheels that are passively actuated by transferring the mass concentration of the system along the wheel axis. Alsalman et al. [5] altered Sfeir's design by replacing the pendulum with a rotating disk, and modeled the system for motion over flat terrain, taking into account the dynamics involved in the disk actuation and the effects of the parameters of the system on the flexible design of the wheels. This paper expands on that work by looking into rough terrain mobility and the constraints involved in the process. ...
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