Posts: 1
Threads: 1
Joined: Mar 2016
20-03-2016, 04:53 PM
I need kinematics of machinery jayakumar book
Posts: 6,843
Threads: 4
Joined: Mar 2015
kinematics of machinery by jayakumar pdf free download
Mechanics: It is that branch of scientific analysis which deals with motion, time and force.Kinematics is the study of motion, without considering the forces which produce that motion. Kinematics of machines deals with the study of the relative motion of machine parts. It involves the study of position, displacement, velocity and acceleration of machine parts.Dynamics of machines involves the study of forces acting on the machine parts and the
motions resulting from these forces.
Plane motion: A body has plane motion, if all its points move in planes which are parallel to some reference plane. A body with plane motion will have only three degrees of freedom. I.e., linear along two axes parallel to the reference plane and rotational/angular about the axis perpendicular to the reference plane. (eg. linear along X and Z and rotational about Y.)The reference plane is called plane of motion. Plane motion can be of three types. 1) Translation 2) rotation and 3) combination of translation and rotation.
Introduction to Kinematics
Kinematics is the branch of science which deals with motion without considering the forces which causes the motion. On the other hand, kinetics is the branch of science which also takes forces which causes motion as well as weight and inertia effects in study.
Kinematic Link and Kinematic Pair
Link: It is defined as a machine element having relative motion with respect to other parts of machine element.
Kinematic pair is defined as a joint of two links which permits relative motion between elements or links. Kinematic pair is constituted when there is mechanical contact between them and having arrangement of mechanism.
Lower pair is said to be constituted when two elements have surface contact between them.
Higher pair is said to be constituted when two element have point contact between them.
Kinematic Chain
Kinematic chain is one in which number of links are so connected that relative motion of any point on a page link with respect to any other point on the other page link follows a governing law
L = 2/3(J+2) Where, L = Number of links, J = Number of Joints
or
J = 3/2(L)-2, Where, H = Number of Higher pairs
One Higher pair = Two lower pair
The criterion for a chain to be constrained:
J+H/2 = 3/2(L)-2,
Where, H = Number of Higher pairs and J =Number of binary joints in chain
If R.H.S. = L.H.S. , Chain is said to be locked.
Mechanism
If the one of the page link of constrained kinematic chain is fixed, it results into 'Mechanism'
A mechanism with four links is called simple mechanism. Mechanism with single degree of freedom are having only even number of links.
Real life example is automobile propelling system which contains links in form of piston, connecting rod and cranks shaft to which flywheel and rear tire is attached.