少学时刚体的平面运动白

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2、vAB wsin1 lulvABABBO0ABAABvvv awacoscos0rvvAB awatantan0lrlvA lvBAAB wvAvBAvBavABO0AvAvBAvBavAvCAvCvAC 2tan2520202022 CAACAACvvrrrvvv w ww ww wCAACvvv ABAB)()(ABvv cossinABvv vB BAABvvv ABAABBvv SAvwAvBAvBvAB)(w ABvBA0 w wS AAvAvMAvLL 。ALLv MAAMvvv LL MAAMvvv w AMvAM SAAvwAvMAvMLwPwAvAP 0 wAPvvAPAvM

3、Av SAAvwAvMAvLLMSAAvwAvMAvMLPSww BPvBPBBvACBPPBvvv AvCvBPv ?SPwS Avw AvwAvPA AvBvPAv BvABSAAvwP wAvS PABOw：Av ， 。 rAB3 rOA BvP AvBvABABBABBPvww coswr332 )(wtgABvAPvAAAB ABwABAAPrvww 333ww rrABOwAvBvPABwOBv研究研究连杆连杆AB：Av0 ABwMAAMvvv Av MMvSAAvBvBSAAvBBv 。0wSPwPSAAvBvBOOv Ov解：解：)(P0 PAvvRvO w（）wBvDvCv,

4、2OBvv ,2OCvv ODvv2 ABCDP 五五 rabRvAvBvCE0wrvvBA cossinCBvv wtantan0rvvBC wwtan0RrRvCC 3033030bAOvA1113ww bBOvB222ww CAACvvv CBBCvvv CBBCAAvvvv 30 cosCBAvv CBBCAAvvvv bvvACB1230 cosw 30222121222460cos2wwww bvvvvvCBBCBBC由几何关系可得：由几何关系可得：方向：方向： CACvv xv ,cos3060ABvv 30cos1sm 231.030 cos30 cos wOAvvAB1sm

5、693. 03 BBDvCDCBvvDEvv 30 cos30601sm 8.0 Ev例题例题8 平面机构中平面机构中, 楔块楔块M: a a =30, v=12cm/s ; 盘盘: r = 4cm , 与与 楔块间无楔块间无滑动求圆盘的滑动求圆盘的w w及轴及轴O的速度和的速度和B点速度点速度解：轴解：轴O, 杆杆OC, 楔块楔块M均作平动均作平动, 圆盘作平面运动，圆盘作平面运动，P为速度瞬心为速度瞬心, cm/s 12vvArad/s 32cos/12/ awrPAvA)(cm/s 343230sin4sinwawrPOvocmcosOBPOOBPOPB72214224212022222

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7、vARvBlvlvCAvAAAAB245sin wAABBvCBv waAvARaBaAnBAatBAanBAtBAABaaaa lvlaAABnBA222 wxy45sin45sin45cos45cosAtBABnBAABaaaaaa 2222,22AAtBAAABvlaavlaa 2222AAtBAABvlalla aAO1OB3203wvAvB0ww OAvAAB03wwrOBvABB AO1OB20215wratB nAatAanBatBanAatAanBAatBAanBAtBAtAnABnBaaaaaa t200203,wawrraratAnA 2022wwrABaABnBA 201

8、223wrBOvaBnB nBAnAtAnBtBaaaaa 60cos30cos30cos60cos100200100200PDrDeDvvv 其中：其中：vDe=vF30cos/FDvv 30cos2 BDPD1 -srad12 PDvDADw1sm 08. 2 PAwvADAvAOABEDCvBPwrv2 AwrvvAB2=0 ABwww OBvBOBEvevrvawrvvveaED reavvv 0 rvOABEDCPtaaaaACnAC CA0 Ca0 tACa2wranAC 2wraanACA aAaAnBatBatBAattaaaaaBAnBABnB A0 nBAa22wranB

9、60cos30cos60cosAtBnBaaa 23waatB 223wa OBatBOBABaAOABEDCPEaEaarnEeatEeaCrEenEeEaaaaaa t00 Crav2wranEe 223wratEe 223wraatEeEa 223wraaEaED O1OO2ABCDvCvBEvA0332ww BEvB0332wwaavvAC 02332ww COvCCOEO1OO2ABCDvCvBvA02130coswavvAAr 06330sinwavvAAe 063ww OAvAeODvAevArArAeAvvv O1OO2ABCD20)31 (waatC aBaBnCatCanCBatCBattaaaaaCBnCBCnC B20waaB 202312wwaaaCOnC 20234wwaaanCB nCBBnCtCaaaa 30cos60cos30cos202)31 (2wa COatCCO20332waatCB 60cos30cosnCBtCBnCaaa 20332wa BCatCBtaaaaABnAB BAO1OO2ABCDaB20waaB 20332waaaatAB 20234wwaaanAB nABatABaCrAaaaa