Fig. 4: Perception and addressing functions of the MPGA.
a Schematic of a mobile robot integrating two sensing units (A0, A1). When the motion of the robot is not controlled by the sensing units, the two units function solely as sensors; when the motion is controlled by the sensing units, they not only sense the external magnetic field but also control the motion of the robot. b Example of magnetic field sensing functionality. As the mobile robot passes through two unknown magnetic fields, the approximate directions of the fields can be inferred from the state transitions of the two units. The green arrow indicates the direction of two magnetic caps when the initial state of A1A0 is 11. The orange arrow indicates the direction of the external magnetic field. The four slices in the pie chart correspond to the angular ranges of the external magnetic field that cause transitions from the initial state 11 to 00, 01, 10, and those that maintain the initial state, respectively. c Addressing robot with reprogrammable trajectories. When the sensing units serve as an automatic control system for addressing, the motion behavior of the robot is governed by the states of the two units. d For a 3 × 3 address array, the relationship between the set of Desired addresses, the corresponding States set, and the magnetic field layout.
