The 6DOF platform was designed and proposed by British engineer Stewart in 1965, so it is also called the Stewart platform. It was originally mainly used as a flight simulator for training aircraft pilots. Compared with the series mechanism, the parallel mechanism has the characteristics of high structural rigidity, strong bearing capacity, high position accuracy and fast dynamic response. In 1978, Professor Hunt put forward the concept of parallel configuration and applied the Gough-Stewart mechanism to the field of industrial robots in view of the shortcomings of the serial manipulators, such as poor stiffness, weak bearing capacity, accumulated errors, and difficulty in solving inverse solutions. Since then, parallel mechanisms have been more and more widely used in error compensation devices, industrial manipulators, space docking technology, flight simulation cockpits, earthquake simulation experience platforms and other heavy-load and high-acceleration applications.
The simulation platform is divided into three types according to the driving mode: pneumatic platform, hydraulic platform, and electric platform; according to the degree of freedom, it can be divided into a 3DOF and a 6DOF platform.
Air pressure platform
The key components are pneumatic cylinders, pneumatic solenoid valves and air compressors. The utility model has the advantages of simple structure, moderate power consumption, low price, no pollution, fast action response, reliable operation, easy maintenance, long service life and wide temperature range. The disadvantage is that the power is small, the noise is large, and the running speed of the platform is uneven.
The key components are hydraulic cylinder, hydraulic solenoid valve (which can be divided into two types: switch valve and proportional valve) and hydraulic pump station. The power is the largest of the three and is suitable for high-load situations. The price is medium, the action is gentler than that of the pneumatic platform, and the noise is low;
Electric platform The key components are electric cylinder, reducer, servo motor, servo motor driver, motion control card, etc. Generally, there are three degrees of freedom and six degrees of freedom. The power is second only to the hydraulic platform. It has the advantages of fast response speed, high sensitivity, precise control, simple structure, high reliability, low noise, cleanliness, and easy maintenance. The disadvantage is that the control circuit is complicated and the cost is high.