In modern hydraulic control system, electro-hydraulic servo valve, as the core control element, is widely used in industrial equipment with high precision and high response. In order to analyze the dynamic performance of servo valve and its influence on the whole system more accurately, the application of simulation technology is particularly important. Among them, ADAMS (Automatic Dynamic Analysis of Mechanical Systems), as an important tool of multi-body dynamics simulation, can effectively simulate the motion characteristics of mechanical systems. The joint simulation of servo valve model and ADAMS is helpful to realize the integrated analysis of hydraulic system and mechanical system, and improve design efficiency and system performance.
First, the basic principle of servo valve
Electro-hydraulic servo valve is a high-precision control element that converts electrical signals into hydraulic output. Its basic function is to adjust the pressure or flow of hydraulic oil proportionally according to the input electrical signals. It is usually composed of torque motor, nozzle baffle and slide valve, and has the characteristics of fast response, high precision and good reversibility.
In the hydraulic servo system, the working state of the servo valve directly affects the control accuracy and dynamic response of the system. Therefore, it is of great significance to accurately simulate its performance in the design stage.
Second, the introduction of ADAMS and its application advantages
ADAMS is a set of virtual prototype simulation software developed by American MSC company, which is mainly used for kinematics and dynamics modeling and simulation of mechanical systems. Its advantages are:
1. Complex mechanical system model can be built;
2. Support multi-body dynamics analysis;
3. Provide abundant kinematic pairs and constraint types;
4. It can be combined with other simulation tools (such as MATLAB/Simulink, AMESim, etc.).
These characteristics make ADAMS an ideal platform for integrated simulation of hydraulic system and mechanical system.
Third, the realization method of joint simulation of servo valve and ADAMS
To realize the joint simulation of servo valve and ADAMS, the following methods are usually adopted:
# 1. Establish the servo valve model through MATLAB/Simulink.
The dynamic characteristics of servo valves are usually described by differential equations or state space models. Using Simulink, the mathematical model of servo valve can be easily established, and the joint simulation can be carried out with the mechanical system model through the interface provided by ADAMS (such as Adams/Control module).
# 2. Modeling with Hydraulics Library
Some professional hydraulic simulation software such as AMESim can also be coupled with ADAMS. By establishing the servo valve model in AMESim, encapsulating it as S function or FMU(Functional Mock-up Unit), and then importing it into ADAMS, the joint simulation of hydraulic and mechanical systems is realized.
# 3. Modeling directly in ADAMS
For the servo valve system with simple structure, the built-in Hydraulic module can also be directly used in ADAMS for modeling and simulation, but this method has some limitations in complex control logic and nonlinear behavior modeling.
Fourth, the application case of joint simulation
In the design of a hydraulic servo control system, the researchers used ADAMS to establish a three-dimensional model of the mechanical actuator, and combined with the servo valve control model in Simulink, carried out system-level joint simulation. The results show that this method can effectively predict the dynamic response time, steady-state error and vibration characteristics of the system, and significantly improve the reliability and optimization efficiency of the system design.
In addition, this method can also be applied to aircraft steering gear control, robot hydraulic drive system, automatic production line and other fields, and has a wide application prospect.
V. Conclusion
As a key component in hydraulic control system, servo valve’s performance directly affects the control accuracy and response speed of the whole system. As a powerful multi-body dynamics simulation tool, ADAMS can effectively simulate the motion behavior of mechanical systems. Through the joint simulation of servo valve and ADAMS, not only the accuracy of system modeling can be improved, but also the product development cycle can be accelerated and the research and development cost can be reduced.
In the future, with the continuous development of simulation technology, the deep integration of servo valve and ADAMS and other multi-domain simulation platforms will provide more powerful technical support for the optimal design of complex electromechanical systems.