Could you suggest me some best motors for robots?

However, one of the most common motor sizes and compatible for hobbyrobotics is in the range of 1.5 volts, and building a simple robot with engines of 1.5 V is simple and fast.

instructions

• Fit the two engines facing each other on the sides of 6 inches of balsa wood base. Make sure they are level and placed at one end of the table or another does not, in the center.
• Place the rubber wheels mounted on the motor shaft and the free wheel turning in the center of the board opposite the two engines mounted. The robot must rest on threewheels evenly when placed.
• Connect motor wires together positive and negative cables to each other.
• Mount the battery in the robot's back too, between the two engines. Connect the positive lead of the pack positive wires attached to the engine.
• Connect the battery negative cable to the negative terminal of the switch. Connect thepositive terminal of the switch to the motor cables "negative together.
• Insert two AA batteries in fully charged battery pack and use the switch. The robot goesaway!