Mechanical arm, a device widely used in the field of robotic technology.
The mechanical arm is the most widely used automated mechanical device in the field of robotic technology. It can be seen in the fields of industrial manufacturing, medical treatment, entertainment services, military, semiconductor manufacturing, and space exploration.
Although their shapes are different, they all have a common feature, that is, they can accept instructions and accurately locate a point in the three-dimensional (or two-dimensional) space for operations.
Mechanical arm type
Mechanical arm is divided into multi-joint mechanical arm, rectangular coordinate system mechanical arm, spherical coordinate system mechanical arm, polar coordinate mechanical arm, cylindrical coordinate mechanical arm, etc. according to the different structure forms.
Mechanical arm structure
The horizontal multi-joint mechanical arm generally has three main degrees of freedom, Z1 rotation, Z2 rotation, and Z movement. By adding X rotation to the execution terminal, Y rotation can reach any coordinate point in the space.
The rectangular coordinate system Mechanical arm has three main degrees of freedom. X movement, Y movement, and Z movement are composed. By adding X rotation, Y rotation and Z rotation to the execution terminal, any coordinate point in the space can be reached.
Mechanical arm function and composition
Mechanical arm function
The arm generally has 3 movements: telescopic, rotating and lifting. The realization of the rotation and lifting movement is completed by the cross arm and the production column. The basic function of the arm is to move the claw to the required position and bear the maximum weight of the workpiece grasped by the claw, as well as the weight of the arm itself.
Mechanical arm composition
(1) Moving components. Such as oil cylinders, air cylinders, racks, cams, etc. are the components that drive the arm to move.
(2) Guiding device. It is to ensure the correct direction of the arm and bear the bending and torsion moment caused by the weight of the workpiece.
(3) Arm. Play the role of connecting and bearing external forces. Parts on the arm, such as cylinders, guide rods, control parts, etc., are all installed on the arm.
In addition, according to the requirements of manipulator movement and work, such as pipelines, cooling devices, stroke positioning devices and automatic detection devices, they are generally installed on the arm. Therefore, the structure, working range, carrying capacity and movement accuracy of the arm directly affect the working performance of the manipulator.
Mechanical arm design requirements
- The arm should have large bearing capacity, good rigidity and light weight
- The movement speed of the arm should be appropriate and the inertia should be small
- The arm movements should be flexible
- High position accuracy
- Strong versatility, can adapt to a variety of operations; good craftsmanship, easy maintenance