A robotic manipulator arm is a versatile and reprogrammable mechanical device designed to move materials, parts, objects, or tools through programmed motions to perform a variety of tasks. These devices consist of a series of jointed segments that create an arm-like structure. A robotic manipulator can automatically handle or move objects based on its degrees of freedom, also referred to as axes. The number of axes corresponds to the number of motors within the robot, with configurations ranging from two to ten or more. In industrial applications, most robots typically have between four to six axes. Six-axis robotic manipulators are particularly common, as their range of motion closely resembles that of a human arm, offering the flexibility necessary to automate numerous industrial processes effectively.
The basic structure of a robotic manipulator consists of rigid links connected by joints. One end of the manipulator is fixed to a base, while the other end is free and designed for various robotic applications. The design of the robotic manipulator influences the reach of its end-effector and the overall work envelope.
Robotic manipulators are generally divided into two main components: the arm/body and the wrist. The arm and body control the movement of objects within the robot's work envelope, such as when the manipulator places a part onto a conveyor. In contrast, the wrist governs the movement of the end-effector, enabling the manipulator to execute its programmed tasks effectively.
Types
Robotic manipulators come in various types, each defined by different joint combinations. These include Cartesian, cylindrical, polar, articulated, SCARA, and delta configurations. Among these, articulated manipulators are the most commonly used and recognized in manufacturing settings. Cartesian manipulators consist of prismatic or sliding joints, providing a rectangular work envelope. Cylindrical and polar manipulators both consist of revolute joints; cylindrical robots operate within a cylindrical work envelope, while polar robots function within a spherical envelope. Both SCARA and delta manipulators utilize parallel joint configurations.
The main types of manipulator robots are Cartesian, cylindrical, spherical, and articulated robots. Each type has its advantages and disadvantages, making them suitable for specific applications.
Applications
All robotic manipulators are equipped with a controller and a teach pendant. The teach pendant is used to program the robotic manipulator, while the controller acts as the "brain," enabling the robot to interpret and execute the programmed operations. The manipulator's performance is influenced by its payload capacity, speed, and repeatability.
Robot manipulators can automate a wide range of applications. Some of the most common uses include automated welding, robotic assembly, material removal, material handling, painting, robotic palletizing, and automated pick-and-place operations. Technological advancements have significantly enhanced the accuracy and precision of robotic manipulators, paving the way for new applications such as robotic 3D printing. As manipulators become increasingly sophisticated, the range of robotic applications expands, making manufacturing processes more efficient, reliable, and productive through industrial robot automation.
