I. Commonly Used Kinematic Configurations
1. Descartes manipulator
Advantages: It is easy to implement through computer control and can easily achieve high precision.
Disadvantages: It hinders work, occupies a large area, has a low movement speed, and poor sealing.
①A series of tasks including welding, handling, loading and unloading, packaging, palletizing, depalletizing, testing, flaw detection, sorting, assembly, labeling, inkjet coding, coding, (soft imitation) spraying, target tracking, bomb disposal, etc.
② It is particularly suitable for flexible operations with multiple varieties and convenient batches. It plays a very important role in stabilizing and improving product quality, increasing labor productivity, improving working conditions, and rapidly updating products.
2. Hinge-type manipulator (joint type)
Articulated robots have all rotating joints, similar to a human arm, and represent the most common structure among industrial robots. Their working range is quite complex.
① Rapid testing and product development for automotive parts, molds, sheet metal parts, plastic products, sports equipment, glass products, ceramics, aerospace, etc.
② Coordinate measurement and error detection for manufacturing quality control in areas such as vehicle body assembly and general mechanical assembly.
③ Rapid prototyping of antiques, artworks, sculptures, cartoon character designs, and figurative products.
④ On-site measurement and testing of complete vehicles.
⑤ Human body shape measurement, manufacturing of medical equipment such as skeletons, human body shaping, medical cosmetic surgery, etc.
3. SCARA manipulator arm
SCARA robots are commonly used in assembly operations. Their most notable characteristic is their high flexibility in motion along the xy-plane and high rigidity along the z-axis, thus exhibiting selective flexibility. This type of robot has found successful applications in assembly work.
① Widely used for assembling printed circuit boards and electronic components
② Moving and picking up objects, such as integrated circuit boards.
③ It is widely used in the plastics industry, automotive industry, electronics industry, pharmaceutical industry and food industry.
④ Moving parts and assembling them.
4. Spherical coordinate type manipulator
Features: The working range near the central support is large, the two rotary drive devices are easy to seal, and the coverage area is large. However, the coordinate system is complex and difficult to control, and the linear drive device has sealing issues.
5. Cylindrical coordinate type manipulator
Advantages: Simple to calculate; the linear section can be hydraulically driven, providing significant power output; capable of reaching into cavity-type machines. Disadvantages: Its arm has limited reach, unable to access spaces near columns or the ground.
The linear drive section is difficult to seal and dustproof; when the rear arm is working, the rear end of the arm may come into contact with other objects within the working range.
6. Redundant mechanisms
Spatial positioning typically requires six degrees of freedom, and additional joints can help the mechanism avoid singular configurations. The image below shows the configuration of a 7-DOF manipulator.
7. Closed-loop structure
A closed-loop structure can improve the rigidity of the mechanism, but it will reduce the range of motion of the joints and the working space will be reduced to a certain extent.
① Sports simulator;
② Parallel machine tools;
③ Micro-manipulation robots;
④ Force sensor;
⑤ Cell manipulation robots in biomedical engineering, capable of cell injection and segmentation;
⑥ Microsurgical robots;
⑦ Attitude adjustment device for large radio telescopes;
⑧ Hybrid equipment, such as SMT's Tricept hybrid robot module, is a successful example of modular design based on parallel mechanism units.
II. Main Technical Parameters of the Robot
A robot's technical parameters reflect its capabilities in performing tasks and its maximum operational performance, and are essential considerations in robot design and application. Key technical parameters of a robot include degrees of freedom, resolution, workspace, operating speed, and payload.
1. Degrees of freedom
The number of independent coordinate axes of motion of a robot. The degrees of freedom (DOF) of a robot refer to the number of independent motion parameters required to determine the position and orientation of the robot's hand in space. The opening and closing of the fingers, as well as the degrees of freedom of the finger joints, are generally not included. The number of DEF of a robot is generally equal to the number of joints. The number of DEF commonly used in robots is generally no more than 5 to 6.
2. Joint
A kinematic pair is a mechanism that allows relative movement between the parts of a robot arm.
3. Workspace
The workspace of a robot refers to the entire spatial area accessible by the mounting points of its arm or hand. Its shape depends on the robot's degrees of freedom and the type and configuration of its joints. A robot's workspace is typically represented using both graphical and analytical methods.
4. Working speed
The distance or angle that the center of the mechanical interface or the center of the tool moves per unit time during uniform motion under working load conditions.
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