You can make a self-balancing robot using two wheels, or a more stable platform using four or more.Ģ driven wheels + one or two idler wheels Common types of wheeled robots Skid steering (using 2, 4 or 6 wheels) When making a tight turn, or turning on spot, tank treads encounter significantly more resistance than wheels as both halves are pushed against the ground perpendicularly to the turning radius. Most users agree that tank tracks look more intimidating, they are far from being a refined method of transportation and have a tendency to 'tear up' the ground beneath them. Military tank manufacturers around the world produce both wheeled and tracked tank models and both offer comparable performance. Tracks are not necessarily a better choice than using multiple driven wheels. The way around this is to add suspension.Ī track system (or linking all wheels with gears or drive belts) also helps to prevent this from occurring. In the image below, the center wheel, chosen mistakenly as the driven wheel, often loses contact with the ground. Increasing the number of drive motors helps the robot to climb steeper inclines by increasing the torque.Īdding “idle” wheels (wheels not connected to a motor) often has the unfortunate consequence of removing weight from the drive wheels resulting in slip and loss of traction. Individuals who use an R/C car as a basis for their robot use rack and pinion steering where one motor is connected to a drive train and the other (usually a servo motor) is used for steering. Six wheeled robots most commonly have either two, four or six drive motors.

Four wheeled robots have either two or four drive motors and use skid steering. A three wheeled robot’s third (rear) wheel usually prevents the robot from falling over. Hobbyists tend to choose skid steering (like a tank) because of its simplicity to design, incorporate and control.

Mobile wheeled or tracked robots have a minimum of two motors which are used to propel and steer the robot. Designing a mobile robot and wondering what wheels (and how many) you should incorporate? You've come to the right place.

Tank tracks vs wheels for robots