Mechanical system
An industrial robot's mechanical system comprises the body, arm, wrist, end effector, and locomotion mechanism, each with several degrees of freedom, thus forming a multi-degree-of-freedom mechanical system. In addition, some robots also possess a locomotion mechanism. If a robot has a locomotion mechanism, it is a walking robot; if it lacks both locomotion and rotation mechanisms, it is a single-arm robot. The end effector is a crucial component directly mounted on the wrist; it can be a two- or multi-finger gripper, or a tool such as a paint gun or welding torch. The mechanical system of an industrial robot functions analogously to the human body (e.g., bones, hands, arms, and legs).
drive system
A drive system primarily refers to the drive device that drives the movement of a mechanical system. Depending on the drive source, drive systems can be divided into three types: electrical, hydraulic, and pneumatic, as well as integrated systems that combine these technologies. This part functions similarly to human muscles.
Electrical drive systems are widely used in industrial robots and can be divided into three types: stepper motors, DC servo motors, and AC servo motors. Early robots primarily used stepper motors, but later DC servo motors were developed, and AC servo motors have also gradually gained application. Some of these drive units directly drive the mechanism's motion, while others use harmonic reducers to slow down the mechanism, resulting in a simple and compact structure.
Hydraulic drive systems offer smooth operation and high load capacity, making them a suitable choice for robots handling heavy loads and machining parts. However, hydraulic drives suffer from drawbacks such as complex piping and difficult cleaning, which limits their application in assembly operations.
Whether electrically or hydraulically driven, robots use pneumatic mechanisms for opening and closing their grippers. Pneumatically driven robots are simple in structure, move quickly, and are inexpensive; however, due to the compressibility of air, their operating speed stability is relatively poor. Nevertheless, the compressibility of air improves the gripper's compliance when grasping or clamping objects, preventing excessive force that could damage the grasped object or the gripper itself. The pressure of a pneumatic system is typically 0.7 MPa, resulting in a small grasping force, ranging from tens to hundreds of Newtons.
control system
The task of the control system is to control the robot's actuators according to the robot's work instructions and the signals fed back from the sensors, so that the robot can complete the prescribed movements and functions.
If the robot lacks feedback capabilities, the control system is called an open-loop control system; if the robot possesses feedback capabilities, the control system is called a closed-loop control system. This part mainly consists of computer hardware and control software. The software primarily comprises a human-machine interface system for communication between humans and the robot, and control algorithms. This part functions similarly to the human brain.
Sensing system
The perception system consists of internal and external sensors. Its function is to acquire information about the robot's internal and external environment and feed this information back to the control system. Internal state sensors detect variables such as the position and velocity of each joint, providing feedback information to the closed-loop servo control system. External state sensors detect state variables between the robot and its surroundings, such as distance, proximity, and contact status, guiding the robot to recognize objects and take appropriate actions. External sensors enable the robot to react flexibly to its environment, endowing it with a degree of intelligence. This part functions similarly to the five senses in a human.
A robot is an automated machine that possesses some intelligent capabilities similar to humans or other living beings, such as perception, planning, movement, and coordination. It is a highly flexible automated machine.
