Measures of Dispersion and Variability: Range, QD, AD and SD
001 mechanisms and kinematics
1. Mechanisms and Kinematics Lecture Notes Reference: Machines and Mechanisms Applied Kinematics by David H. Myszka
2. Machines and Mechanisms Machinesare devices used to accomplish work. Mechanism is the mechanical portion of a machine that has the function of transffering motion and forces from a power source to an output. Reference: Machines and Mechanisms Applied Kinematics by David H. Myszka
4. Kinematics and Kinematic Analysis Kinematics is the study of the geometry of motion. Kinematic Analysis deals with the determination of position, displacement, rotation, speed, velocity, and acceleration. Reference: Machines and Mechanisms Applied Kinematics by David H. Myszka
5. Terminologies Planar mechanism are mechanisms that exhibit motion such that parts move in parallel plane. Linkages is a mechanism where all parts are connected to form a closed chain. Frame is one part of the closed chain that exhibits no motion and serves as a reference for the motion of all other parts. Reference: Machines and Mechanisms Applied Kinematics by David H. Myszka
6. Terminologies Links are individual parts of the mechanisms. They are rigid bodies and are connected with other links to transmit motion and forces. Joint is a movable connection between links and allows relative motion between links. Reference: Machines and Mechanisms Applied Kinematics by David H. Myszka
7. Two Primary Types of Joints Revolute joint Sliding joint Reference: Machines and Mechanisms Applied Kinematics by David H. Myszka
8. Higher Order Joints Higher order joints are type of joints that allows for both rotation and sliding of the two links that it connects, such as in a cam joint and gear joint. Cam joint Gear joint Reference: Machines and Mechanisms Applied Kinematics by David H. Myszka
9. Simple Link Simple link is a rigid body that contains only two joints, which connects it to other links. Crank is a simple link that is able to complete a full rotation about a fixed center. Rocker is a simple link that oscillates through an angle, reversing its direction at certain intervals. Reference: Machines and Mechanisms Applied Kinematics by David H. Myszka
10. Complex Link Complex link is a rigid body that contains more than two joints. Point of interest is a point on a link where the motion is of special interest. Reference: Machines and Mechanisms Applied Kinematics by David H. Myszka
11. Symbols Used in Kinematic Diagrams Reference: Machines and Mechanisms Applied Kinematics by David H. Myszka Simple Link Slider Joint Simple Link (with point of interest) Cam Joint Complex Line Gear Joint Pin Joint
12. Example 1: Draw the kinematic diagram of a shear shown that is used to cut and trim electronic circuit board laminates. 1. Base 2. Handle 3. Cutting blade 4. Bar that connects the cutter with the handle. 5. X point of interest Reference: Machines and Mechanisms Applied Kinematics by David H. Myszka
13. Example 2: Draw the kinematic diagram of a pair of vice grips shown. 1. Base 2. Bottom handle 3. Bottom jaw 4. Bar that connects the top and bottom handle. 5. X and Y point of interest Reference: Machines and Mechanisms Applied Kinematics by David H. Myszka
14. Degree of Freedom Degree of Freedom or Mobility “F” is the number of independent inputs required to precisely position all links of the mechanism with respect to the ground. It can also be defined as the numbers of drivers required to operate the mechanism. Reference: Machines and Mechanisms Applied Kinematics by David H. Myszka
16. Example 3: Draw a kinematic diagram of a toggle clamp, using the clamping surface and the handle as points of interest. Also compute the degrees of freedom for the clamp. Reference: Machines and Mechanisms Applied Kinematics by David H. Myszka
17. Example 4: Draw a kinematic diagram of a shearing device, using the end of the handle and the cutting edge as point of interest. Also compute the degrees of freedom for the clamp. Reference: Machines and Mechanisms Applied Kinematics by David H. Myszka
