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Crc Press Mechatronics Handbook 2002 By Laxxuss Episode 3 Part 13

Tham khảo tài liệu 'crc press mechatronics handbook 2002 by laxxuss episode 3 part 13', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Uref F m vmax - 00 0v FIGURE 33.7 Nonlinear MM of the first stages of the servovalve. resulting force which actuates on the valve spool. 2 XF xv t 2 . Dv. 0 . xv t w0v. Xv t - - m XF Xv t k - 2. Dv. 00v. Xv t - w0v . xv t where k 33.3 m The displacement xv obtained based upon the mentioned equations is implemented in SIMULINK using the scheme from Fig. 33.7. This module of nonlinear MM includes two stages of electrohydraulic axis the electrohydraulic and the hydromechanical one. The corresponding equations for the four flows that go through the servovalve are QpA a p -D . Jr x0 xv t .7pp - pA t xv e -x0 xmax QAT aD . p . Dv . . x0-xv t .7pA t - pT xv e -xmax x0 33.4 QPB aD . p . Dv .Jr . x0-xv t . VpP - pB t xv e -xmax x0 QbT a p . Dv . Jr . x0 xv t .7Pb t - pT xv e -x0 xmax where QPA m3 s the flow to the hydraulic motor from pump to the chamber A of the motor QAT m3 s the flow from the chamber A to reservoir QPB m3 s the flow from pump to the chamber B of the motor Qbt m s the flow from the chamber B to reservoir aD - the discharge coefficient Dv m the spool s diameter x0 m the dimension of the lap of the spool xv m the spool s displacement pA N m the fluid pressure in chamber A pB N m the fluid pressure in chamber B kg m fluids density. The flows which are transmitted to LHM and evacuated from LHM are QA and QB which are computed as following Qa Qpa -qat Qb Qbt- Qpb 33.5 The lap of the spool is considered to be zero x0 0 and therefore the static characteristic is linear around the origin and also in the rest. With Qo aD n Dv - J2 r the flow equations become Qpa Qo . xv Jpp - pA QPB Q0 . -xv .7pP - pB QAT Q0 . -xv .JpA - pT QBT Q0. xv pB - pT 33.6 Nonlinear Mathematical Model of Linear Hydraulic Motor The differential equations based on which the MM of the linear hydraulic motor LHM was achieved are i. the equation of the dynamic equilibrium of the forces reduced to the motor s rod and ii. the equation of movement and flow continuity. 2002 CRC Press LLC Uref F m .