Modular robots have been originally envisioned as a universal, robust, and low cost alternative to a variety of specialized robots with fixed body structure and functions. Unfortunately, even after two decades of studies in this field, most researchers agree that these advantages are yet to be fully realized. One of the serious problems that hinders the progress in this area is the prohibitively high cost of fabrication and operation of known modular robotic systems, which limits the modular robotic community to only few specialized labs at select universities.

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