Research On Virtual Prototype Of Hydraulic 6-DOF Parallel Mechanism

Parallel mechanism has many advantages of good rigidity, large bearing capacity, no accumulative error, high precision, fast system dynamic response, etc. Hydraulic drive not only provides accurate rectilinear movement, but also has advantages of high precision, fast response and wide-range speed regulation. Hydraulic parallel mechanism is widely used in fields of industry, ship craft and space flight.With development of science and technology, new ways of design techniques emerge. Virtual prototype has been developing very quickly in recent years. Combining robot study with virtual prototype, research on kinematics, dynamics, tracking, route planning and performance analysis could be carried out in virtual environment. It could enhance reliability and design efficiency.This paper was targeted at the modeling of hydraulic parallel mechanism virtual prototype. In recent researches, parallel mechanism virtual prototype focused on dynamic modeling, driving system modeling was seldom involved, and modeling of hydraulic system was always simplified. This paper was intended to build a hydraulic parallel mechanism virtual prototype including hydraulic system, mechanism and control strategy. Meanwhile, the hydraulic system would be built in an accurate way and with good expandability.This paper focuses on the accurate modeling of the hydraulic system. Researches on technical issues of the hydraulic system modeling were studied. By adjusting parameters of the servo-valve model, characteristic curves of frequency response as required were acquired; Based on friction characteristic of oil cylinder in low speed, a detailed friction model was built; Built a single hydraulic control system based on PID strategy; Completed the AMESim and ADAMS interface with non-mass strategy in AMESim.Accuracy analysis on parameter-setting of the AMESim & ADAMS interface was performed. Some problem in co-simulation was found and solved.Kinematic numerical experiments like step response, slope response, sine response and path tracking were performed on this virtual prototype. Also, some characteristic analysis was performed.The hydraulic parallel mechanism virtual prototype built in this paper provides a good platform for dynamics analysis and control strategy study of hydraulic parallel mechanism.