Modular Self-Reconfigurable Robotic Systems: A Survey on Hardware Architectures

Table 2

Comparison of MSRR designs.

Category				Robot	Shape	DOF	Coupling		Number of Conn. faces		Ref.
Struct.	Reconf.	Form ftr.	Locom.				Interface	Actuator	Activ./M	Passv./F
Lattice	Detrmn.	Mini	Coord.	Microunit I	Square	2D	Latch	SMA	2F	2M	[15]
				Microunit II	Cubical	3D	Latch	SMA	3F	3M	[16]
		Macro	Coord.	Metamorphic I	Hexagon	2D	Lock	DC motor	3M	3F	[6–8]
				Metamorphic II	Square	2D	Lock	DC motor	2M	2F	[7]
				Fracta	Triangular	2D	Elect. mag.	Current	3M	3F	[9]
				Vertical	Cubical	2D	Key lock	—	0	4	[17]
				3D unit	Cubical	3D	Hooks	DC motor	6	0	[11, 12]
				Molecule	Cuboid	3D	Elect. mag.	Current	0	6	[10, 102]
				Crystalline	Cuboid	2D	Key lock	DC motor	2M	2F	[18]
				I-cubes	Cubical	3D	Key lock	Servo motor	2M	6F	[13, 14]
				Telecubes	Cubical	3D	Swtc. mgnts.	SMA	6 Dl. faces		[19]
				ATRON	Octagonal	3D	Hooks	DC motor	4M	4F	[30, 31]
				EM-cube	Cubical	2D	Elect. mag.	Current	2	2	[20]
				M-blocks 2D	Cubical	2D	Perm. mag.	—	0	6	[21]
				M-blocks 3D	Cubical	3D	Perm. mag.	—	0	6	[22]
			Mobile	Petro	Tetrahedral	3D	Latch	Manual	0	4	[32]
	Stocst.	Mini	Extern.	Pebbles	Cubical	2D	El-pm. mag.	Current	4	0	[24]
				Miche	Cubical	3D	Rot. pr. mg.	Motor	3	3	[23]
		Macro	Extern.	Stochastic 2D	Cubical	2D	Elect. mag.	Current	4	0	[25]
				Stochastic 3D	Cubical	3D	Elect. mag.	Current	6	0	[26]
				Prog. parts	Triangular	2D	Perm. mag.	DC motor	3	0	[27]
				X-bot	Cubical	2D	Perm. mag.	SMA	4	0	[28, 29]
Chain	Detrmn.	Macro	Mobile	CEBOT I	Cuboid	3D	Latch	SMA	1M	1F	[33]
				CEBOT II	Cuboid	3D	Latch	DC motor	1M	1F	[34]
				ACM-R1	Rectangle	2D	Latch	Manual	0	2	[35]
				ACM-R2	Rectangle	3D	Latch	Manual	0	2	[36]
				ACM-R3	Rectangle	3D	Latch	Manual	0	2	[37]
				Millibot	Elliptical	2D	Latch	SMA	1M	1F	[38]
				UNI-Rover	Cylind. arm	3D	Latch	Servo motor	1	1	[103]
				Amoeba - I	Cuboid	3D	Latch	Manual	0	2	[39, 40]
				JL-1	Trapezoid	3D	Latch	DC motor	1M	1F	[41]
				JL-2	Trapezoid	3D	Gripper	DC motor	1M	1F	[42]
				Thor	Cuboid. arm	3D	Gripper	DC motor	1	0	[43]
				Steering	Cuboid	2D	Latch	—	1M	1F	[104]
			Co-ord.	Polypod	Cubical	3D	Latch	Manual	0	6	[44]
				CONRO	Cuboid	3D	Latch	SMA	1M	3F	[45–48]
				Polybot I	Cubical	3D	Latch	Manual	1M	1F	[50]
				Polybot II	Cubical	3D	Latch	SMA	1M	1F	[51]
				Polybot III	Cubical	3D	Latch	SMA	1M	1F	[51]
				Yamor	Semicylnd.	3D	Velcros	Manual	0	4	[54]
				GZ-1	Cubic	3D	Latch	Manual	0	4	[53]
				Transmote	Cubic	3D	Key lock	Manual	1M	2F	[52]
				ModRED	Cuboid	3D	Latch	Solenoid	2 Dl. faces		[49]
Hybrid	Determn.	Macro	Mobile	S-BOT	Cylindrical	3D	Gripper	Motor	1	1	[55–59]
				M^3	L shaped	3D	Hooks	DC motor	3 DL. conn.		[63]
				M^3 express	L shaped	3D	Latch	SMA, servo	3 DL. conn.		[64]
				iMobot	Cuboidal	3D	Latch	Manual	0	6	[65]
				SMORES	Cubical	3D	Perm. mag	DC motor	3	1	[67]
				Trimobot	Hexagonal	3D	Hooks	DC motors	1M	6F	[68]
			Co-ord.	M-Tran I	Semicylnd.	3D	Perm. mag	SMA	6	2	[69, 105]
				M-Tran II	Semicylnd.	3D	Perm. mag	SMA	6	2	[71, 72]
				M-Tran III	Semicylnd.	3D	Hooks	DC motor	6	2	[73]
				Superbot	Cuboid	3D	Latch	Manual	0	6	[74, 75]
				Molecubes	Cubical	3D	Elect. mag.	Current	6	0	[77]
				CKBot	Cubical	3D	Perm. magnets	Manual	0	4	[76]
				UBot	Cubical	3D	Hooks	DC motor	2	2	[78–80]
				Roombots	Cuboidal	3D	Latch	Manual	0–10	0–10	[81]
				Neurobot	Cubical	3D	Latch	DC motor	1M	1F	[5]
				Soldercubes	Cubical	3D	Binder mat.	Current	6	0	[83, 84]
Truss	Determn.	Macro	Co-ord.	Tetrobot	Cylindrical	3D	Spherical jnt.	Manual	2M	3F	[85, 86]
				ORTHO-BOT	Linact	3D	Split toroid	Manual	0	2	[87]
				Odin	Cylindrical	3D	CCP jnt.	Manual	2M	12F	[88]
				Morpho	Cubical	3D	Cubic jnt.	Manual	1	6	[89]
				Shape shift.	Amorphous	3D	3-way pipe	Manual	2M	3F	[91]
				Hinge	Cylindrical	3D	18-axis node	Manual	2M	18F	[90]
				Factory Flr.	Cylindrical	3D	Grippers	Couples	6M	2F	[92]
Free Fr.	Determn.	Micro	Coord.	MEMS	L shaped	2D	Alignment	Voltage	—	—	[100, 101]
		Mini	Coord.	Claytronics	Cylindrical	2D	Electr. mag.	Current	24	0	[94–96]
			Coord.	Catom	Cylindrical	2D	Electrodes	Voltage	8	0	[99]
		Macro	Coord.	Slimebot	Cylindrical	2D	Velcros	Pnu. air cyld.	0	6	[97, 98]
			Coord.	Transform.	Cylindrical	2D	Perm. mag.	—	6	2	[93]