Hardware architectures of the Self-Reconfiguring Modular Robot

The hardware architectures of the SELF-RECONFIGURING MODULAR ROBOT, as well as the paradigm for categorising robots, are evolving in tandem with technological advancements. CEBOT, a prototype consisting of heterogeneous independent parts capable of binding together, was the first prototype produced in the SELF-RECONFIGURING MODULAR ROBOT study, and since then, the research has been focused to the development of systems capable of forming different structures mimicking biological organisms. Yim et al. [2, 3] proposed two classes for modular robotic systems: one based on the structures generated by the SELF-RECONFIGURING MODULAR ROBOT, and the other based on reconfiguration procedures. Under the structures category, Gilpin and Rus [4] added a few more subclassifications by including research from microelectronic mechanical systems (MEMS) and other recent breakthroughs in  SELF-RECONFIGURING MODULAR ROBOT by the time of publication. SELF-RECONFIGURING MODULAR ROBOT systems were classified by Moubarak and Ben-Tzvi [5] based on mobility of individual modules and coordinated structures, as well as form factors. The categories presented thus far are based on the most up-to-date research in recent SELF-RECONFIGURING MODULAR ROBOT technologies, prototypes, and other materials accessible at the time of publication. Due to current advanced designs and features of robots, contemporary research in SELF-RECONFIGURING MODULAR ROBOT is yielding solutions that fall in the middle of past categories, and identifying a category and subcategory for SELF-RECONFIGURING MODULAR ROBOT robots is becoming challenging.

When independent SELF-RECONFIGURING MODULAR ROBOT are brought together, the widely accepted classification is in the perspective of possible structural formations, and five subcategories are recognised under structures, according to current SELF-RECONFIGURING MODULAR ROBOT research: lattice, chain, hybrid, truss, and free-form.

The SELF-RECONFIGURING MODULAR ROBOT for lattice constructions is inspired by atomic structures such as cubic centred lattices, tetrahedrons, and so on, and is equipped with actuators to create comparable structures. Due to limitations in actuator assemblies, individual robotic units occupy distinct positions in space and lack the ability to achieve random positions/orientations if necessary.. Due to their fixed actuator placements in 2D and 3D space, lattice structures enable simple control mechanisms and rarely require closed loop control. Robotic units in the chain category are usually serially connected and capable of building complicated structures such as snakes, centipedes, and so on.These robots' actuators are set up in such a way that their end effectors can move about in space at random. Chained system control is more difficult, as it frequently necessitates feedback to confirm the position of modules in space when reconfiguring structures. In comparison to lattice and chain robotic structures, hybrid designs offer more benefits due to their ability to quickly adapt to changing environments forming both lattice, chained and mixture of both. Due to the use of telescopic linkages and heterogeneous units for building structures, the SELF-RECONFIGURING MODULAR ROBOT with truss-based designs supports the development of random structures, but requires complex algorithms for handling structure assembly and formation.The category of "free-form" In terms of connecting and detaching from the system, SELF-RECONFIGURING MODULAR ROBOTS are often more adaptable. They have the ability to build random structures and, in most cases, retain weak links between neighbours. In terms of bonding rigidity, chain and hybrid structures differ from free-form structures.

SELF-RECONFIGURING MODULAR ROBOT's complex mobility skills are the result of coordinated activities of many individual units aggregated in various structures. The actuator-sensor assemblies implanted in separate robotic modules are responsible for the aggregation capabilities (autonomous/semiautonomous/manual) in SELF-RECONFIGURING MODULAR ROBOT for allowing complex movements through reconfiguration.Because the SELF-RECONFIGURING MODULAR ROBOT designs with wheels are capable of building lattice or chain structures depending on the design, they can be classified as mobile in Figure 1 under locomotion. The bulk of lattice and chain systems are built without wheels on individual components, hence movement is only achieved through robot cooperation. For nonwheeled systems, the grouping of independent components necessitates some human interaction. These SELF-RECONFIGURING MODULAR ROBOT designs belong to the coordinated subcategory of the locomotion category (see Figure 1). The SELF-RECONFIGURING MODULAR ROBOT designs that rely on environmental stimulus/disturbances are referred to as the external subcategory under locomotion in Figure 1.