What are the requirements for the position precision design of the manipulator?

What are the requirements for the position precision design of the manipulator?

The position precision of the mechanical hand of the injection molding machine is an important indicator to measure the working quality of the manipulator, which includes the position setting precision and the repetition positioning precision. Generally speaking, positional positioning accuracy refers to repetitive positioning accuracy. The accuracy of general position accuracy depends on the position control mode and the accuracy and stiffness of the moving parts of the manipulator. In addition, it is also related to the weight and speed of the manipulator.

At present, the industrial manipulator used by most of the control points, wherein, the stroke switch and potentiometer as control element to control the position of low precision (more than 1mm), the positioning accuracy of the fixed block control can achieve high (+0.5mm or more), the potential of servo system can obtain location accuracy the control (the control mode is suitable for high speed and heavy load conditions), mechanical hand to get higher position precision, in addition to the use of advanced control method, the structure also pay attention to the following questions:

1. the stiffness of the manipulator, the moment of weight, the inertia force and the buffering effect directly affect the position precision of the arm.

2. add the positioning device and the travel inspection mechanism.

3. the coordinate form of the manipulator is selected reasonably. The position precision of the Cartesian coordinate manipulator is high, and its structure and motion are relatively simple and the error is small. Error and rotary motion is amplified when the size of the error, when the angular position when the arm is longer, the greater the error; joint type manipulator because of its complex structure, positioning the proximal end is determined by the mutual joint angle, the error is accumulated error, and poor accuracy, its position it is more difficult to ensure accuracy.