Parts of a Robotic Arm

By Brenton Shields

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Robotic arms are widely-used tools that are capable of lifting heavy or hazardous materials that human workers could not otherwise handle. They have been used for decades in factories and laboratories and are a staple science project for middle or high school children. Like other robots, robotic arms consist of a variety of different parts that all contribute to making it properly function.


Controllers are the main processors of the robotic arms and act as their brains. They can either act automatically as programmed or allow for manual operation by outputting instructions directly from a technician. They are essentially the control consoles of the robotic arms and come in a variety of styles according to what kind of processing power is needed. Some controllers in large factories are complex computer systems, while other controllers, like the ones found in science project kits, are simple joysticks.


The arm is the main section of the robotic arm and consists of three parts: the shoulder, elbow and wrist. These are all joints, with the shoulder resting at the base of the arm, typically connected to the controller, and it can move forward, backward or spin. The elbow is in the middle and allows the upper section of the arm to move forward or backward independently of the lower section. Finally, the wrist is at the very end of the upper arm and attaches to the end effector.

End Effector

The end effector acts as the hand of the robotic arm. It is often composed of two claws, though sometimes three, that can open or close on command. It can also spin on the wrist, making maneuvering material and equipment easy.


Drives are essentially the motors in between joints that control the movement and maneuvers. They typically use belts similar to what is found in car engines.


Sensors are more often found on advanced robots. Some are riddled with sensors that allow them to sense their environment and react accordingly. For example, they prevent collisions between two robots who may be working in close proximity or allow the robot to adjust its grip on a fragile object to prevent damaging it.