《液压起重机俯仰运动的动态响应外文文献翻译、中英文翻译、外文翻译》由会员分享，可在线阅读，更多相关《液压起重机俯仰运动的动态响应外文文献翻译、中英文翻译、外文翻译（20页珍藏版）》请在金锄头文库上搜索。
1、外文文献Dynamic responses of hydraulic crane during luffing motionAbstractBased on the complete dynamic calculation method that was developed in our previous work, closed simulations for determining the dynamic responses of hydraulic crane during luffing motion with consideration of the cylinder drive s
2、ystem and luffing angle position control have been realized. Using Lagranges equation and the multi-body theory, the flexible model of crane luffing motion is established. The generalized cylinder driving forces are formulated with the virtual work principle. Coupling the boom structure, hydraulic a
3、ctuator and luffing angle position control system, the total system equations are established. The calculation results show that the dynamic responses of crane are more sensitive to the luffing acceleration, in comparison with the luffing velocity. It is seen that this method is very effective and c
4、onvenient for crane luffing simulation. It is also reasonably to see that the proposed complete dynamic method can be further used for optimal control of crane motion. Keywords: Dynamic response; Crane luffing motion; Multi-body theory; Hydraulic cylinder; Angle position control 1. IntroductionBoom
5、luffing is one of the fundamental motions of rotary cranes. Luffing motion is usually driven by hydraulic motors or cylinders in modern mobile cranes. During start-up or braking of the drive system, the dynamic forces can be produced, which are harmful not only to crane security, but also to health
6、of crane drivers. Because of the payload pendulum during boom motion, the dynamic forces can be very significant. For this reason, many studies on crane dynamics have been reported in the literature. Most of the published articles concentrated on dynamic responses of cranes during rotating and hoist
7、ing motion.Only a few works have payed attention to the luffing motion of crane. In our previous works, we have found that the method of “kinematic forcing” with the assumed profiles of the driving velocity and acceleration could not accurately describe the driving outputs during start-up and brakin
8、g of the system. It is seemed that these assumed start-up and braking velocity profiles are based on experience. Because of the large inertia forces of the crane structure, for start-up and braking of crane system, the driving force and torque generated by the motor or cylinder are time complicated
9、functions. These driving forces pay an important rule in exerting dynamic responses and control effects. To improve this situation, a new method for dynamic calculation of mobile cranes has been proposed in our previous work. In this method, the flexible model of the steel structure is coupled with
10、the model of the drive system. In that way the elastic deformation, the rigid body motion of the structure and the dynamic behavior of the drive system can be determined with one integrated model. We called as “complete dynamic calculation for mechanism”. Using the proposed method, we have presented
11、 complete dynamic models for rotating and hoisting motion of rotary crane. In this paper, the luffing dynamic behavior will be considered. The calculation will be realized for a hydraulic mobile rotary crane. Because the boom structure subjects not only elastic deformation, but also has large rigid
12、rotation, the flexible multi-body dynamic theory will be used to describe the boom luffing motion. The drive system is cylinder, which is described using hydraulic and control theory. The generalized cylinder driving forces will be derived using the virtual work principle. The total system will be d
13、escribed using the system state equations. The simulations of crane luffing motion will be carried out. 2. The method of complete dynamic calculationThe principle of complete dynamic calculation that is proposed in our previous work is based on the integrated model from flexible multi-body model of
14、the mechanism and the mathematical model of the drive system. The inputs are the desired state values of the mechanism, such as position or velocity. The outputs are the dynamic responses of the complete system, which consists of the mechanism system and the drive system with control. See Fig. 1. Fi
15、g. 1.The principle of complete dynamic calculation for mechanism.Using Lagranges equation, the mechanism motion is given by (1)where T is total kinetic energy, q is the vector of the generalized coordinates, Qin is the vector of the internal generalized forces, Qa is the vector of the applied extern
16、al forces, Qd is the vector of the generalized driving forces and are the Lagrange multiplies, which describe the constraint forces between the connecting bodies. The constrained conditions of the bodies can be written in the following vector equation:C(q,t)=0 (2)The drive system has a significant influence on the dynamic responses of the driven mechanism and should be included in the dyna
