Stewart platform, also called a 6dof platform, research on the Stewart platform began in 1965. German engineer Stewart proposed a six-degree-of-freedom parallel mechanism as a flight simulator. The current mechanism of the classic Stewart motion platform is mainly composed of two upper and lower platforms and six telescopic rods and hinges connecting them to the upper and lower platforms. Among them, the upper platform is a load platform and can be moved; the lower platform is usually a base and is fixed on the ground. The Stewart parallel platform can use the telescopic movement of six struts to enable the load platform to achieve joint movement of six degrees of freedom in space within the working range (i.e., pitch, roll, yaw rotation, and front and rear, left and right, up and down translation), and has It has the advantages of good stiffness, high precision, strong load-bearing capacity and good dynamic characteristics, so it is widely used in industrial, medical, aerospace and other fields.
The inverse solution algorithm is an algorithm used to determine the motion parameters of each actuator (such as a hydraulic cylinder or an electric motor) on the Stewart platform to achieve the desired platform motion. The goal of the inverse solution algorithm is to calculate the length or joint angle of each actuator from a given platform attitude (position and attitude). The core idea of these algorithms is to convert the required platform posture into the motion parameters of the actuator. The following are the general steps of the inverse solution algorithm:
1. Define the coordinate system of the platform and base, as well as the initial parameters of each actuator.
2. According to the required platform posture, calculate the position of each point on the platform relative to the base coordinate system.
3. Using trigonometric geometry or other mathematical methods, calculate the length or joint angle of each actuator to move the point on the platform to the desired position.
4. Optimize the calculated parameters taking into account actual mechanical limitations and motion smoothness.
The uses of inverse solution algorithms include:
1. Motion control: The Stewart platform is widely used in applications that require high-precision, multi-degree-of-freedom motion, such as flight simulators, robot operations, material handling, and assembly.
2. Medical field: In surgical robots and image-guided surgeries, the Stewart platform can provide highly precise motion control to help doctors perform minimally invasive surgeries and precise operations.
3. Aerospace: The Stewart platform can be used to test and simulate the dynamic performance of aircraft, as well as conduct simulated training of manned or unmanned aircraft.
4. Simulation and entertainment: In virtual reality, games and entertainment devices, the Stewart platform can simulate various sports and experiences.
5. Earthquake simulation: In earthquake engineering research, the Stewart platform can simulate earthquake vibrations and be used to test the seismic performance of buildings and structures.
In short, the inverse solution algorithm of the Stewart platform has important applications in many fields. They allow the platform to perform highly precise and complex movements, providing key technical support for applications in industry, medical, aerospace and other fields.