THEORYMECHANICS1902Chapter 8 Composite motion of pointsCollege of Mechanical and Vehicle EngineeringWang Xiaojun
College of Mechanical and Vehicle Engineering Wang Xiaojun THEORY MECHANICS Chapter 8 Composite motion of points
Chapter8 Composite motion of points> 8.1 The concepts of absolute motion, relative motion andinvolving motion> 8.2 The velocity synthesis theorem of point> 8.3 The associated motion is the synthesis theorem ofacceleration at translational time points> 8.4 The involved motion is the synthesis theorem ofacceleration at the point of rotation
➢ 8.1 The concepts of absolute motion, relative motion and involving motion ➢ 8.2 The velocity synthesis theorem of point ➢ 8.3 The associated motion is the synthesis theorem of acceleration at translational time points ➢ 8.4 The involved motion is the synthesis theorem of acceleration at the point of rotation Chapter8 Composite motion of points
8.1 The concept of absolute motion relative motioninvolving motionDecomposition and synthesis of motionThemotionofpointP(complex)synthesisDecompositionVThemotionofpointPrelativetothefuselageMotionof fuselage
Decomposition and synthesis of motion The motion of point P (complex) Decomposition synthesis The motion of point P relative to the fuselage Motion of fuselage 8.1 The concept of absolute motion relative motion involving motion
8.1 The concept of absolute motion relative motioninvolving motion1.Twocoordinate systemsStatic system: Coordinate system that consolidatesthe surface of the earthDynamic system: A frame of reference that consolidates an object movingrelativetothesurfaceoftheEarthNote that the coordinate system can beextended indefinitelymotionof2.ThreekindsofsportspointsAbsolute motion: Motion of the moving point relative to the static systemRelative motion:The motion of a moving point relative to an active systemTranslational motion: Motion in a dynamic system as opposed to a staticsystem→Motion of Rigid Body
1. Two coordinate systems Static system: Coordinate system that consolidates the surface of the earth Dynamic system：A frame of reference that consolidates an object moving relative to the surface of the Earth 2. Three kinds of sports Absolute motion: Motion of the moving point relative to the static system Relative motion: The motion of a moving point relative to an active system Translational motion: Motion in a dynamic system as opposed to a static system 8.1 The concept of absolute motion relative motion involving motion motion of points Motion of Rigid Body Note that the coordinate system can be extended indefinitely
8.1 The concept of absolute motion relative motioninvolving motionA point M on the rim1The motion trajectory of M:Mrouletteabsolutemovement②circlerelativemovementMotionin a dynamic system:horizontaltranslationtranslationalmotionx
x x? y? y M o A point M on the rim The motion trajectory of M: ① roulette—absolute movement ②circle—relative movement Motion in a dynamic system: horizontal translation—translational motion 8.1 The concept of absolute motion relative motion involving motion