UCM first unit : ME 2026

Do find the link which gives you the material for the first unit which was discussed in the class. Pl go through it and give your comments.

First unit : Click here to download

AJT Technical paper: Just go through it

Electrically activated hydraulic pump gives life to a boy

A 15-year-old Italian boy has undergone a permanent artificial heart implant, which is expected to allow him to lead another 20 to 25 years of 'normal life'. This is made possible with the help of " Electrically activated hydraulic pump".

click here to read the complete news.

Gears an introduction

The topics which we discussed in the class is given in nutshell. Students are here by asked to go through all the terminologies , and understand the concepts in gears.
Gears
Gears are machine elements that transmit motion by means of successively engaging teeth. The gear teeth act like small levers.
1 Gear Classification
Gears may be classified according to the relative position of the axes of revolution. The axes may be
1. parallel,
2. intersecting,
3. neither parallel nor intersecting.
Here is a brief list of the common forms. We will discuss each in more detail later.
• Gears for connecting parallel shafts
• Gears for connecting intersecting shafts
• Neither parallel nor intersecting shafts
Gears for connecting parallel shafts
1. Spur gears
2. Parallel helical gears
3. Herringbone gears (or double-helical gears)
4. Rack and pinion (The rack is like a gear whose axis is at infinity.)

Gears for connecting intersecting shafts
1. Straight bevel gears
2. Spiral bevel gears

Neither parallel nor intersecting shafts
1. Crossed-helical gears
2. Hypoid gears
3. Worm and wormgear

The fundamental law of gear-tooth action may now also be stated as follow (for gears with fixed center distance)
The common normal to the tooth profiles at the point of contact must always pass through a fixed point (the pitch point) on the line of centers (to get a constant velocity ratio).

The Involute Curve

The curve most commonly used for gear-tooth profiles is the involute of a circle. This involute curve is the path traced by a point on a line as the line rolls without slipping on the circumference of a circle. It may also be defined as a path traced by the end of a string which is originally wrapped on a circle when the string is unwrapped from the circle. The circle from which the involute is derived is called the base circle.

Terminology for Spur Gears

In the following section, we define many of the terms used in the analysis of spur gears. Some of the terminology has been defined previously but we include them here for completeness.
Pitch surface : The surface of the imaginary rolling cylinder (cone, etc.) that the toothed gear may be considered to replace.
• Pitch circle: A right section of the pitch surface.
• Addendum circle: A circle bounding the ends of the teeth, in a right section of the gear.
• Root (or dedendum) circle: The circle bounding the spaces between the teeth, in a right section of the gear.
• Addendum: The radial distance between the pitch circle and the addendum circle.
• Dedendum: The radial distance between the pitch circle and the root circle.
• Clearance: The difference between the dedendum of one gear and the addendum of the mating gear.
• Face of a tooth: That part of the tooth surface lying outside the pitch surface.
• Flank of a tooth: The part of the tooth surface lying inside the pitch surface.
• Circular thickness (also called the tooth thickness) : The thickness of the tooth measured on the pitch circle. It is the length of an arc and not the length of a straight line.
• Tooth space: The distance between adjacent teeth measured on the pitch circle.
• Backlash: The difference between the circle thickness of one gear and the tooth space of the mating gear.
• Circular pitch p: The width of a tooth and a space, measured on the pitch circle.
• Diametral pitch P: The number of teeth of a gear per inch of its pitch diameter. A toothed gear must have an integral number of teeth. The circular pitch, therefore, equals the pitch circumference divided by the number of teeth. The diametral pitch is, by definition, the number of teeth divided by the pitch diameter. That is,

That is, the product of the diametral pitch and the circular pitch equals .
• Module m: Pitch diameter divided by number of teeth. The pitch diameter is usually specified in inches or millimeters; in the former case the module is the inverse of diametral pitch.
• Fillet : The small radius that connects the profile of a tooth to the root circle.
• Pinion: The smaller of any pair of mating gears. The larger of the pair is called simply the gear.
• Velocity ratio: The ratio of the number of revolutions of the driving (or input) gear to the number of revolutions of the driven (or output) gear, in a unit of time.
• Pitch point: The point of tangency of the pitch circles of a pair of mating gears.
• Common tangent: The line tangent to the pitch circle at the pitch point.
• Line of action: A line normal to a pair of mating tooth profiles at their point of contact.
• Path of contact: The path traced by the contact point of a pair of tooth profiles.
• Pressure angle : The angle between the common normal at the point of tooth contact and the common tangent to the pitch circles. It is also the angle between the line of action and the common tangent.

Computer based test for kinematics of machinery

Glad new for III mech students!

In order to enchance the learning of the students in the subject kinematics, a computer based interactive learning model is proposed . This is going to be launched by me shortly . Students in III semester in our college would be benefited out of this.
The highlight of it is the learning model will have objective questions with multiple answers.It will evaluate the learner and suggest the correct answer, display the time taken by the test taker, gives input to the staff about the tough and easy part of the subject and so on.. Let us experience the new stuff.

KOM- இயந்திர இயங்கியல் 113302 / ME 2203

ME 2203 KINEMATICS OF MACHINERY
QUESTION BANK
1. List the classifications of cam followers based on shape.
2. Define rubbing velocity.
3. State Kennedy’ s theorem.
4. Define Corioli's component of acceleration.
5. State the expressions for maximum velocity and acceleration of a follower moves with
Cycloidal motion.
6. What is prime circle of a cam? What is the radial distance between the prime circle and
base circle for a cam with knife edge follower?
7. Define pitch curve of the cam.
8. Explain tangential and normal component of acceleration.
9. Construct a tangent cam and mention the important terminologies on it.
10. Define transmission angle of a four bar linkage. What is the effect of transmission angle
on mechanical advantage?
11. What are the properties of instant centers?
12. How is the number of instant centers in a mechanism calculated?
13. Give the difference between the fixed and permanent instant centres.
14. Write a note on the location of instant centres.
15. Explain the terminologies in cams a) prime circle b) lift c)pitch curve d) Base circle
16. Give the difference between the radial and tangential cam.
17. Sketch the different types of followers.
18. Draw the displacement diagram[ free hand sketching] for a SHM follower: outstroke 180 0, return 1800 lift 40 mm.
19. Sketch the velocity and acceleration diagram [ free hand sketching] for uniform velocity follower assuming 40 mm lift , 1200 deg outstroke, 600 dwell, 90 0 return stroke and 90 0 dwell.
20. Explain the term pressure angle with respect to cams.

16 marks
1. (i) Find the number of instantaneous centers for a six link mechanism. State the use of instantaneous centre method in kinematic analysis. (4)
(ii) Crank of a slider crank mechanism rotates clockwise at a constant speed of 300 rpm, crank and connecting rod are of lengths 150 mm and 600 respectively. Determine the following; at a crank angle of 45° from inner dead centre position (1) Linear velocity and acceleration of the midpoint of connecting rod (2) Angular velocity and angular acceleration of the connecting rod. (12)
2. (i) Explain the following terms : (1) Prime circle (2) Pressure Angle related to cams. (4)
(ii) Draw the profile of a disc cam to give uniform motion and uniform velocity during outstroke of 25 mm to a knife edge follower during first half revolution. Return of cam is also of similar uniform motion with uniform velocity during remaining half revolution. Minimum radius of the cam is 25 mm. Assume that the axis of knife edge follower passes through cam axis.
3. i) Briefly explain the features of mushroom followers. (4)
(ii) Draw the profile of a cam to give following motion to a flat faced reciprocating follower. (1) Follower to have a stroke of 20 mm during 120° of cam rotation. (2) Follower to dwell for 30° of cam rotation (3) Follower to return to initial position during 120° of cam rotation. (4) Follower to dwell for remaining 90° of cam rotation. The base circle radius is 40 mm and the follower axis coincides with cam axis of rotation. (12)
4. (i) Compare instantaneous center method and velocity polygon method for velocity
analysis of mechanisms. (4)
(ii) A four bar linkage has following dimensions: Crank AO2 = 150 mm; Link AB = 450 mm;
Link BO4 = 300 mm; Link O2O4 = 200 mm. Link O2O4 is fixed. Find the angular acceleration of links AB and BO4 when the crank is rotating with a constant angular velocity of 200 rad/s counter clockwise and also positioned of 45° to horizontal. (12)
5. Draw the profile of a cam to give following motion to a reciprocating follower with a flat face:
(i) Follower to have a stroke of 20 mm during 120° of cam rotation. (ii) Follower to dwell for 30° of cam rotation. (iii) Follower to return to its initial position during 120° of cam rotation. (iv) Follower to dwell for remaining 90° of cam rotation. Minimum radius of cam = 25 mm. Out stroke and return stroke of the follower are simple harmonic.
6.A cam with a minimum radius of 25 mm, rotating in clockwise direction with a uniform
speed of 100 rpm is to be designed to give the motion for a roller follower as follows. (i) To raise through 50 mm during 120° rotation of cam with SHM. (ii) Fully raised through next 30°. (iii) To lower during next 60° with UAUR. (iv) Dwell for the remaining period. Draw the profile of the cam when the line of stroke of the follower is offset by 15 mm from the axis of the camshaft.

7. Draw the profile of disc cam to give uniform acceleration and retardation out stroke of 25
to a knife edge follower during first half of revolution. Return of cam also takes place with
uniform motion during remaining half of cam revolution. Assume minimum radius of cam as 25 mm.

8. The driving crank AD of the quick-return mechanism, as shown in figure, revolves at a uniform speed of 200 r.p.m. Find the velocity and acceleration of the tool-box R, in the position shown, when the crank makes an angle of 60°with the vertical line of centers PA. What is the acceleration of sliding of the block at B along the slotted lever PQ?Refer the picture in the top.

Students design competetion

Design of autonomous underwater vehicle for for ocean observation
STAGES OF SELECTION
• Students through their educational institution can apply for this project
• Team should have 5 students and should be multidisciplinary
• PDF Format : max 10 pages; A4 size; Arial 10; 1.5 spacing; pdf
• NIOT through a panel of experts will scrutinize these entries and select the successful entries qualifying for Phase I
• A mentor will be identified who could associate with this group in developing the
concept.
• CDR
• NIOT shall also extend his expert guidance through state- of- the- art facility and
industrial experience. NIOT will appoint a Mentor who shall guide the team in
preparing CDR. Then selected teams would be asked to make a presentation at NIOT
• On the basis of the CDR review next level of selection (Phase II) will be done
• The successful teams would be asked to submit Engineering Design Model
• The winning team may be able to participate in the International AUV competition in
USA
• NIOT s research vessel facility would be extended to understand the practical
challenges involved while working offshore

KINEMATICS OF MACHINERY- ME 2203

The resources available in the blog are given in the following link.

Resources for kinematics of machinery ME 2203


This is a small test for your understanding in Kinematics of Machinery



Click here to atempt the test

UCM MODEL PAPERS

Find the 3 sets of model papers for the subjects Unconventional machining process.
You may find it useful for preparing for university exams

MODEL PAPERS : CLICK TO DOWNLOAD

UCM anna university question papers

Dear all

Find the link below to download the previous year question papers for the subject Unconventional machining process.
All best for your exams.

Click here to download the question papers

Project report format

Follow the link to download the format prescribed by anna university to submit the Project report.

Project report format

Feed back - UCM

I am happy that most of the students had an interest towards the subject and my lectures created a positive impact. Due to restriction in time and facility some of the presentations and videos are not shown in the class. I shall upload them in a week.

Previous question papers will be uploaded in site few days.

As informed in the class ,the topic for Assignment is " Material removal mechanism in Various Unconventional machining process" [ Atleast 10 process have to be presented].

Who should submit?
1. List of students whose name was read.
2. Students who need to enhance their credits.

Last Date for submission: 25.03.2010

Projects available

I am looking to recruit a small number of interested , motivated individuals to work remotely on projects in the following domain:
Final year mechanical students can start if they are willing to work.
1. Robotic manipulators
2. Link analysis using Adams
3. Solar tracking
4. Design of robotic arms
5. simulation using Labview
6. analysis using matlab

Interested individuals can contact me for clarifications through email or use the "comment" link .

ECH- Electro Chemical Honing