This document summarizes different mechanisms for straight line motion, including the Paucellier mechanism and Robert mechanism. The Paucellier mechanism uses six rigid bars of fixed lengths arranged to produce exact straight line motion from one point. The Robert mechanism is a four bar linkage that converts rotary motion into approximate straight line motion. Both mechanisms have applications in machinery for converting rotational motion into reciprocal or linear motion.

1. STRAIGHT LINE MOTION
MECHANISM
Submitted to:
Mr. N.S.GAIRA
DEPARTMENT OF
MECHANICAL ENGINEERING
SUBMITTED BY:
ABHISHEK JOSHI
ROLL NO - 07
B.TECH (M.E) IV SEM

2. CONTENT
 WHAT IS MECHANISM ?
 STRAIGHT LINE MOTION MECHANISM
 PAUCELLIER MECHANISM
 APPLICATIONS OF PAUCELLIER MECHANISM
 ROBERT MECHANISM
 APPLICATIONS OF ROBERT MECHANISM

3. WHAT IS MECHANISM ?
 Number of rigid bodies arranged in such a way that motion of one body
causes constrained and predictable motion to the other.
 Transmits and modifies motion.

4. STRAIGHT LINE MOTION MECHANISM
 Converts rotary motion into a straight line motion.
 Developed by James Watt for reciprocating piston of steam engine.
 Classified in two types:
1- Exact straight line mechanisms:- Paucellier mechanism, Hart
mechanism, Scott-Russel mechanism, Kempe mechanism,etc.
2- Approximate straight line mechanisms:- Modified Scott-Russel
mechanism, Grasshopper mechanism, Watt mechanism, Robert
mechanism, etc.

5. STRAIGHT LINE MECHANISMS

6. PAUCELLIER MECHANISM
 Invented in 1864.
 Also knows as Paucellier-Lipkin linkage.
 First true planar straight line mechanism.
 Named after a French army officer Charles-Nicolas Peaucellier and a
Lithuaninan mathematician Yom Tov Lipman Lipkin.
 Exact straight line motion mechanism.

7. GEOMETRY
 6 bars of fixed lengths.
 OA=OC
 AB=BC=CD=DA, forming a rhombus.
 O is fixed.
 B moves around O.
 Straight line motion obtained from point D.

8. WORKING

9. PHYSICAL APPLICATION

10. ROBERTS MECHANISM
 Converts rotary motion to approximate straight line motion.
 Developed by Richard Roberts.
 Four bar linkage.
 AC=BD
 CD || AB (fixed link)
 ABCD forms trapezium.
 P traces an approximate straight line motion.

11. WORKING

12. APPLICATION

13. THANK YOU