Anatomy of a 6-axis robot (3D)

← Robot list · 6-axis robot page

Turn the robot with the mouse or your finger. Click an axis (a coloured circle or a card) to light up its ring and its axis and to read its description, press X-ray to look inside at the motors, gearboxes, controller and cables, and move each joint with its slider.

Turns the whole robot around its vertical axis. Its motor and gearbox sit in the base.

Tilts the upper arm forward and backward. It carries the weight of the whole arm, so it has the biggest motor.

Extends or folds the forearm.

Rotates the wrist assembly around the forearm axis.

Tilts the tool up and down. When J5 = 0, the axes J4 and J6 line up: a wrist singularity.

Spins the gripper or the tool around its own axis: it sets the final tool orientation.

What is inside each joint?

Servo motor (brushless): turns fast with little torque.
Gearbox (harmonic or cycloidal): slows the motor down by 50 to 200 times and multiplies the torque by the same factor.
Encoder and brake: the encoder measures the angle; the brake holds the arm when the power is off.
Cable harness: power and signals pass through the hollow links to the wrist and the tool.
Controller: the computer and the drives that run the servo loops (in the base or in a cabinet next to the robot).

The angles of this 3D model are those of the drawing, with a zero chosen for display: they differ by a constant from the DH angles of the robot page. The model is simplified: the real inside depends on the make.