“…As Tables 1 and 2 show, five types of adhesion technologies (magnetic [13,14], pneumatic [15,16], mechanical [17], electrostatic [1,18,19], and chemical adhesion [20][21][22]) and six types of locomotion mechanisms (legs [23], wheels [24,25], tracks [26], slides [27], wires [7], and multi-linked modules [28][29][30]) were compared. A + or − marker means that the selected type was suitable or unsuitable, respectively, for use in meeting a particular requirement.…”