The four bar chain mechanism

about four bar chain and recent advancements in four bar chain mechanism

1. The F our B ar Chain Mechanis m Prepared By Milan Makwana 190043119046

2. The Four Bar Chain It is much preferred device for mechanization and control of motion due to its simplicity and versatility It consist of four rigid links which are connected in the form of a quadrilateral by four pin joint. Fig shows link 1 is fixed and other links are in motion.

3. The Four Bar Chain It is impossible to have a four bar linkage if length of one of the link is greater than the sum of the other three. A variety of useful mechanism can be formed from a four link mechanism through slight variation such as changing the character of the pairs,proportion of links and many complex link mechanism can be formed formed from combination of two or more such four link mechanism

4. Flexibility in four bar chain Is the simplest of all closed loop linkage Have three moving link , one fixed link and 4 pin joints There is only one constraint another linkage , which defines a definite motion

5. Inversions of four bar chain Beam engine Watts indiacator mechanism Connecting rod of locomotive

6. Beam engine A part of mechanisms of a beam engine which consists of four links , is shown In fig In this mechanism when the crank rotates about the fixed centers A the lever oscillates about a fixed centre D. The end E of the lever CDE is connected to a piston rod rod which reciprocates due to the rotation of the crank. In other words, the purpose of this mechanism is to converts rotary motion into reciprocating motion

7. Watts indicator mechanism A WATT'S indicator mechanism which consist of four links, the four links are A, AC, CE and BFD. The displacement of the link BFD is directly proportional to the gas or steam pressure, this pressure of gas/steam used act on the indicator plunger. complete/clear lines indicates the position at starting time of mechanism and the dotted lines represents the position when the gas/steam pressure acts on indicator plunger. The link E used move upwards when indicator plunger raises by the help of gas pressure, and the remaining links used to change there position according pressure act on indicator plunger.

8. Connecting rod of locomotive In this there is four links A,B,C,D link AB is fixed and link DC is connecting rod Link AD is driver and link CB is driven.

9. Latest advancements in four bar chain in HPVC ground vehicle The steering mechanism for human power vehicle Where the tire has to rotate equal angle with or some preferred angle more than handle The two pairs of equal links are selected to design and fabricate the steering mechanism for HPV obeying grass off criterion.

10. Four bar chain in robotics To improve the operating performance of robots end-effector , a humanoid robot hand based on coupling four-bar linkage was designed . An improved transmission system was proposed for the base joint of the thumb. a prototype of the humanoid robot hand was produced by a three-dimensional printer, and a kinematics simulation example and the workspace solving of the humanoid robot hand were carried out.

11. T hank you.