Tom Lab 01-12-2006 Latest Shamsu

INTERNATIONAL ISLAMIC UNIVERSITY MALAYSIA

KULLIYYAH OF ENGINEERINGDEPARTMENT OF MECHATRONICS ENGINEERING

Laboratory Manual

MCT 2110Theory of Machines and Mechanisms

EXPERIMENT 1

Kinematics analysis of SLIDER CRANK mechanism

1.0 Objectives:

1. To obtain input-output relation of Slider-crank mechanism experimentally.2. To calculate input-output relations using analytical and graphical methods 3. To calculate mobility.

2.0 Required Equipment

Slider-crank mechanism

3.0 Procedure

1. Rotate the crank starting from the position corresponding to the left dead center of the slider.2. Record the slider displacement (h), for each 15° of crank rotation angle (φ).3. Using graph paper plot displacement h (φ), versus angle φ.4. Differentiate graphically h (φ) to obtain h'(φ).5. Differentiate graphically h'(φ) to obtain h"(φ).

6. Assuming that the crank rotates with a speed n = 700 RPM, determine the position, velocity and acceleration of the slider corresponding to the time t = 10s after the motion has been started from zero position of the crank.

7. Change the coupler link in the mechanism and repeat-the steps from 1 to 6. Draw all the graphs on the same graph paper. For convenience, use different colors to draw the lines.

8. Compare the results obtained for the mechanisms with different coupler-links with that of the corresponding analytical methods.

Note: Attach this manual together with your lab report.



Laboratory Manual


EXPERIMENT 2

Kinematic analysis of Four-bar linkage

1.0 Objective:1. To obtain input to output relation and analysis of Four-bar linkage.2. To calculate mobility and check Grass-off condition.


Links of different lengths and pins

3.0 Procedure 1. Dimensional synthesis

Using the Grashof conditions select the lengths of the first, second and third links in such a way that you can obtain crank-rocker, double-crank and double-rocker mechanism.

The length of the ground link is constant and equal to ________________mm

LengthMechanism

Link l(Input)

Link 2 (Coupler)

Lmk3 (Output)

Total length S + L

Total length P + Q

Crank-rockerDouble-crankDouble-rocker

2. Kinematics analysisa. Rotate the input link of all obtained mechanisms starting from its zero position.b. Record in the table the angular position φout of the output link for each 15° (or 10°) of input

link's rotation φin.

No. of observations

Input angle φin

Output angleφout

φ ׳out. φ" out.

1.2.3.

c. Using graph paper plot the graph φout =f(φin ) approximately to scale.d. Differentiate graphically φout to obtain φ ׳

out. e. Differentiate graphically φ ' out to obtain φ" out.

f. Only for crank-rocker and double-crank mechanisms assume that crank rotates with speed N = 700.RPM. Determine angular position φout , velocity ωout and acceleration αout of the output link corresponding to the time t = 10s after the motion has been started from the zero position of the crank.

Note: the graphs of the different mechanisms must be drawn on different sheets of graph papers.

g. Change the length of one of the links for the case of only crank-rocker mechanism and repeat the experiment

h. Compare the results of the experiments.




Laboratory Manual


EXPERIMENT 3

Kinematics analysis of Slotted Link mechanism

1.0 Objective:

1. To obtain input-output relation of Slotted link mechanism experimentally.2. To analyze input-output relation of slotted link mechanism using analytical calculations.3. To calculate mobility.


Slotted link mechanism

3.0 Procedure 1. Count the number of moving links N, the number and types of kinematic joints fi and determine the number of DOF of this mechanism using following formula

F = 3(N-1)-2f1 –f2

2. Rotate crank starting from the position corresponding to the left dead center of the slider.

3. Record in the table the position (h) of the slider for each 15° of cranks rotation (φ).

No. of observations

Input angle φ

Output h

h (φ )׳ h" (φ)

1.2.3.

4. Using graph paper plot the graph h(φ) approximately to scale, where h is the displacement of the slider and φ is angular rotation of the crank.

5. Differentiate graphically h(φ) to define the graph h'(φ).

6. Differentiate graphically h'(φ) to define the graph h"( φ).


8. Give an example of a machine that uses the above mechanism.




Laboratory Manual


EXPERIMENT 4

Kinematics analysis of Geneva mechanism

1.0 Objective: 1. To obtain input to output relation of Geneva mechanism experimentally.2. To analyze Geneva mechanism and compare results with experiment. 3.To calculate mobility.


Geneva mechanism

3.0 Procedure

1. Count the number of moving links N, the number and types of kinematic joints fi, and determine the number of DOF of this mechanism using following formula

F = 3(N-1)-2f1 -f2

2. Rotate crank starting from its zero position until it completes one full revolution.

3. Record in the table the positions of Geneva wheel (φout) for each 5° of input crank's rotation (φin) while Geneva wheel is in the state of motion.

4. Using graph paper plot the graph φoutt versus φin approximately to scale.

5. Specify from the graph interval Δφin corresponding to the periods of motion and dwell of the Geneva wheel respectively.

6.What is the total number of motions and dwells during one full revolution of theGeneva wheel? How many revolutions performed by input crank during one full revolution of the Geneva wheel?

7. Differentiate graphically φout to define the graph φ'out

8. Differentiate graphically φ'out to define the graph φ"out

9. Assuming that the crank rotates with a speed n = 700 rpm, determine the position, velocity and acceleration of the slider corresponding to the time t = 2.5 s after the motion has been started from zero position of the input crank.

10. Give an example of a machine that uses the above mechanism.




Laboratory Manual


EXPERIMENT 5

Kinematics analysis of Cam mechanism

1.0 Objective:

1. To obtain input to output relation of Cam mechanism experimentally.2. To analyze Cam mechanism and compare results with experiment.3. To calculate mobility.

2.0 Equipment Required

Different Cam mechanisms

3.0 Procedure

1.Rotate the cam starting from the position corresponding to the bottom dead center of the follower.2. Record in the table the displacement h (mm) of the follower, for each 15° of Cam's rotation (φ).

3.Using graph paper plot displacement h (mm), versus angle φ approximately to scale.4.Differentiate graphically h (φ) to obtain h'(φ).5.Differentiate graphically h'(φ) to obtain h"( φ).

6. Assuming that the crank rotates with a speed n = 700 rpm, determine the position, velocity and acceleration of the slider corresponding to the time t = 10s after the motion has been started from zero position of the follower.

7. Change the cam and follower in the mechanism and repeat the steps 1 to 6. Draw all the graphs on the same sheet of graph paper. For convenience, use different colors to draw graphs of mechanisms with different links.

8. Compare the results obtained for the mechanisms with different links.




Laboratory Manual


EXPERIMENT 6

Kinematics analysis of Gear trains

1.0 Objectives:

1. To obtain input to output relation of gears in Gear trains experimentally.2. To obtain input to output relation of gears in Gear trains theoretically.


Gears of different sizes, gear holders and pins

3.0 Procedure

1 . Count the number of moving links N, the number and types of kinematic joints,fi and determine the number of DOF of compound gear train using following formula

F = 3(N-1)-2f1-f2

2. Draw schematic diagram of the gear train and count number of teeth on each gear.3. Define experimentally drive ratio on the mechanism using formula

Where nin, and nout are number of revolutions of input and output links respectively (for simplicity you can take either nin or nout as unit 1)

4. Determine drive ratio of the mechanism analytically using number of teeth of the gears.

5. Compare result obtained in 3 and 4.6. Reassemble mechanism to obtain epicyclic (planetary) gear train and repeat steps form 1 to 5.

7. Compare drive ratios of compound and epicyclic gear trains. Which one is bigger?




Laboratory Manual


EXPERIMENT 7

Kinematics analysis of SCOTCH YOKE mechanism

1.0 Objectives:1. To obtain input to output relation 2. To analysis of SCOTCH YOKE mechanism3. To calculate mobility.


Crank, Output shaft and slider

3.0 Procedure

1 . Count the number of moving links N, the number and types of kinematics joints fi and determine the number of DOF of compound gear train using following formula

F = 3(N-1)-2f1-f2

2. Draw schematic diagram.

3. Rotate the crank starting from 0°, with an increment of about 15°.

4. Record the horizontal displacement (h) of the slider, for every angle (φ) increment.

5. Plot displacement h (φ), versus angle φ graph on graph paper. • .

6. Differentiate graphically h (φ) to obtain h'(φ).

7. Differentiate graphically h'(φ) to obtain h"(φ).


9. Derive the mathematical relation of h (φ) and φ. Justify your graphical answers of h'(φ) and h"(φ) with mathematical one.




Laboratory Manual


EXPERIMENT 8

Kinematics analysis of

WITHWORTH QUICK RETURN mechanism

1.0 Objective: 1. To obtain input to output relation 2. To analysis of WITHWORTH QUICK RETURN mechanism. 3. To calculate mobility. 4. To calculate Time ratio.

2.0 Equipment Required Crank, Output shaft and slider

3.0 Procedure1. Count the number of moving links N, the number and types of kinetics joint fi and determine the

number of DOF of this mechanism using following formula.

F = 3(N-1)-2f1-f2


3. Rotate crank starting from the position corresponding to the left dead center of the slider.

4. Record in the table the position (h) of the slider for each 15° of cranks rotation (φ).

5. Using graph paper plot the graph h(φ) approximately to scale, where h is the displacement of the slider and cp is angular rotation of the crank.

6. Differentiate graphically h (φ) to define the graph h'(φ).

7. Differentiate graphically h'(φ) to define the graph h"(φ).

8. Assuming that the crank rotates with a speed n = 700 RPM, determine the position, velocity and acceleration of the slider corresponding to the time t= 10s after the motion has been started from zero position of the crank.

9. Give an example of a machine that using the above mechanism.




Laboratory Manual


EXPERIMENT 9

Kinematics analysis of HOOKE'S JOINT mechanism

1.0 Objective:1. To obtain an input to output relation 2. To analysis for the HOOKE'S JOINT at different angular misalignment.3. To calculate mobility.

2.0 Equipment Required Input Crank and Output crank

3.0 Procedure

1. Count the number of moving links N, the number and types of kinetics joint fi and determine the number of DOF of this mechanism using following formula.

F = 3(N-1)-2f1-f2


3. Misalign the shafts by positioning the marker at base plate to angle to 20°.

4. Record the output crank angle (φout) for every input crank angle (φio) increment of about 5 °.

5. Repeat step 2 by increasing the misalignment angle to 40°.

6. Using graph paper plot φout versus φin approximately to scale.

7. Differentiate graphically φout to obtain φ'outt.

8. Differentiate graphically φout to obtain φ''outt.

9. Assuming that the input crank rotates with a speed n = 700 RPM, determine the angular position, velocity and acceleration of the output crank corresponding to the time t = 10s after the motion has been started from zero position of the input crank.

10. Repeat step 4, 5, 6 and 7 for different misalignment angle in step 3.

11. Explain your observation on φ , φ'out, and φ''out, with respect to different angular misalignment.

12. Give an example of machine that using the above mechanism.




Laboratory Manual


EXPERIMENT 10

Kinematics analysis of OLD HAM COUPLING mechanism

1.0 Objective:1. To obtain an input to output relation 2. To analysis for the OLDHAM COUPLING at different parallel misalignment.3. To calculate mobility.

2.0 Equipment Required Input Crank and Output crank

3.0 Procedure

1. Count the number of moving links N, the number and types of kinetics joint fi and determine the number of DOF of this mechanism using following formula.

F = 3(N-1)-2f1-f2


3. Misalign the shafts by positioning the marker at input crank base plate to 10 mm.

4. Record the output crank angle (φout) for different input crank angle φin ) increment of about 5°.

5. Repeat step 2 by increasing parallel misalignment to 2cm and 3cm.

4. Using graph paper plot φout versus φ'in approximately to scale.

5. Differentiate graphically φout to obtain φ'out

6. Differentiate graphically φ'out to obtain φ''out.

7. Assuming that the input crank rotates with a speed n = 700 RPM, determine the angular position, velocity and acceleration of the output crank corresponding to the time 10 s after the motion has been started from zero position of the input crank.

8. Repeat step 4, 5, 6 and 7 for different parallel misalignments in step 3.

9. Explain your observation on φout, φ'out and φ''out with respect to different parallel misalignments.

10. Give an example of machine that using the above mechanism.


Tom Lab 01-12-2006 Latest Shamsu

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