A List of Things You Need to Make a Robot

Tools

• To make a robot, you'll need a set of standard hand tools, such as pliers; an Allen wrench, which is an L-shaped hexagonal thin steel rod, both sides of which fit a socket; and screwdrivers, to assemble a robot's mechanical parts. A hacksaw and utility knife cut and trim parts to size. Tools such as a multimeter, soldering iron and wire strippers work on the robot's electronic parts.

Stepper Motors

• Stepper motors provide precise movement for the robot's arms and wheels. A stepper motor is a direct current electric motor that turns its shaft a discrete number of degrees when it receives pulses from a computer. If the computer sends the motor 50 pulses, for example, that may turn the motor exactly 180 degrees. The computer can change the stepper motor's direction, making it an ideal source of mechanical power.

Microprocessor and Software

• The robot gets its behavior from a computer controller called a microprocessor. The microprocessor serves as the robot's "brain," connecting to the robot's sensors and stepper motors. Programming you write for the microprocessor processes data from the sensors and turns it into actions for the motors to carry out. While it can be challenging and time-consuming, this can also be the most fun part of making a robot. You can continue to improve your robot's programming long after you finish its physical construction.

Sensors

• Most robots now have sophisticated sensors that turn sound and light and other elements into electronic signals. A motion sensor detects obstructions in the robot's path and determines their distance from the robot. Accelerometers and gyroscopes gauge the robot's motion and orientation. Programming in the microprocessor reads electronic signals from the sensors, allowing the robot to perform actions based on its immediate environment.

Battery Pack

• Being an electrical device, your robot needs a source of electric power. Unless you want it to drag a power cord behind it, a rechargeable battery pack makes sense. A small robot can get by on a set of D cell batteries. Larger robots might use lithium-ion or sealed lead-acid batteries. Generally, larger and more expensive batteries provide more power and can handle more charge-discharge cycles.

Wheeled Platform

• A robot needs a platform upon which you can put the motors, computer and other parts. Though a few robot designs use legs to move about, most have wheels. The platform must be big and sturdy enough to carry the battery pack, sensors and motors. It helps if the platform can handle bumps, drops and other mishaps. Plan on a bigger platform if you want your robot to carry a payload.