group a christopher back josephashwin franklin kwongvoon wong chen lin windshield wiper soft top...
TRANSCRIPT
![Page 1: Group A Christopher Back Josephashwin Franklin Kwongvoon Wong Chen Lin Windshield Wiper Soft Top Mechanism](https://reader035.vdocuments.mx/reader035/viewer/2022081801/55141dec550346d8488b56a9/html5/thumbnails/1.jpg)
Group AChristopher Back
Josephashwin FranklinKwongvoon Wong
Chen Lin
•Windshield Wiper
• Soft Top Mechanism
![Page 2: Group A Christopher Back Josephashwin Franklin Kwongvoon Wong Chen Lin Windshield Wiper Soft Top Mechanism](https://reader035.vdocuments.mx/reader035/viewer/2022081801/55141dec550346d8488b56a9/html5/thumbnails/2.jpg)
Cascading Four-bar Mechanisms
•Open Loop Four-bar Configuration- Used in Industrial robots- Usually requires multiple actuators to control motion
•Pantograph Linkage- Originally used in scaled diagrams- Linkages consist of Parallelograms
![Page 3: Group A Christopher Back Josephashwin Franklin Kwongvoon Wong Chen Lin Windshield Wiper Soft Top Mechanism](https://reader035.vdocuments.mx/reader035/viewer/2022081801/55141dec550346d8488b56a9/html5/thumbnails/3.jpg)
http://auto.howstuffworks.com/convertible2.htm
![Page 4: Group A Christopher Back Josephashwin Franklin Kwongvoon Wong Chen Lin Windshield Wiper Soft Top Mechanism](https://reader035.vdocuments.mx/reader035/viewer/2022081801/55141dec550346d8488b56a9/html5/thumbnails/4.jpg)
Open Loop Four-bar
L= 4, J1= 3, J2= 0 DOF = M =3
Pantograph Linkage
L= 4, J1= 3, J2= 0 DOF = M = 1
![Page 5: Group A Christopher Back Josephashwin Franklin Kwongvoon Wong Chen Lin Windshield Wiper Soft Top Mechanism](https://reader035.vdocuments.mx/reader035/viewer/2022081801/55141dec550346d8488b56a9/html5/thumbnails/5.jpg)
Reason for Four-Bar Design Pantograph serves as a locking mechanism Use of Limiting Position simplifies complex
motion Parallel linkages prevent further motion when
collinear
![Page 6: Group A Christopher Back Josephashwin Franklin Kwongvoon Wong Chen Lin Windshield Wiper Soft Top Mechanism](https://reader035.vdocuments.mx/reader035/viewer/2022081801/55141dec550346d8488b56a9/html5/thumbnails/6.jpg)
![Page 7: Group A Christopher Back Josephashwin Franklin Kwongvoon Wong Chen Lin Windshield Wiper Soft Top Mechanism](https://reader035.vdocuments.mx/reader035/viewer/2022081801/55141dec550346d8488b56a9/html5/thumbnails/7.jpg)
The four-bar linkage has been show as the simplest possible pin-jointed mechanism
Allows for single degree of freedom controlled motion
![Page 8: Group A Christopher Back Josephashwin Franklin Kwongvoon Wong Chen Lin Windshield Wiper Soft Top Mechanism](https://reader035.vdocuments.mx/reader035/viewer/2022081801/55141dec550346d8488b56a9/html5/thumbnails/8.jpg)
Grashof Condition
S+L<P+QClass I case:• Ground either link
adjacent to the shortest and you get a crank-rocker
• The shortest link will fully rotate
• the other link pivoted at the ground will oscillate
![Page 9: Group A Christopher Back Josephashwin Franklin Kwongvoon Wong Chen Lin Windshield Wiper Soft Top Mechanism](https://reader035.vdocuments.mx/reader035/viewer/2022081801/55141dec550346d8488b56a9/html5/thumbnails/9.jpg)
Tandem system is widely used in the front windshield
One Motor runs both wipers
Parallelogram linkage translates motion to wipers
![Page 10: Group A Christopher Back Josephashwin Franklin Kwongvoon Wong Chen Lin Windshield Wiper Soft Top Mechanism](https://reader035.vdocuments.mx/reader035/viewer/2022081801/55141dec550346d8488b56a9/html5/thumbnails/10.jpg)
DOF= 3*(6-1)-2*7=1
Four and Six-bar is a parallelogram linkage.
Duplicate the rotary motion of the driver crank at the driven bar.
Most Common Type of Windshieldmechanism
![Page 11: Group A Christopher Back Josephashwin Franklin Kwongvoon Wong Chen Lin Windshield Wiper Soft Top Mechanism](https://reader035.vdocuments.mx/reader035/viewer/2022081801/55141dec550346d8488b56a9/html5/thumbnails/11.jpg)
The coupler of the parallelogram linkage is in curvilinear translation
Remaining at the same angle while all points on it describe identical circular paths
Crank Rocker Input toWindshield Wiper
![Page 12: Group A Christopher Back Josephashwin Franklin Kwongvoon Wong Chen Lin Windshield Wiper Soft Top Mechanism](https://reader035.vdocuments.mx/reader035/viewer/2022081801/55141dec550346d8488b56a9/html5/thumbnails/12.jpg)
![Page 13: Group A Christopher Back Josephashwin Franklin Kwongvoon Wong Chen Lin Windshield Wiper Soft Top Mechanism](https://reader035.vdocuments.mx/reader035/viewer/2022081801/55141dec550346d8488b56a9/html5/thumbnails/13.jpg)
Varying ???
![Page 14: Group A Christopher Back Josephashwin Franklin Kwongvoon Wong Chen Lin Windshield Wiper Soft Top Mechanism](https://reader035.vdocuments.mx/reader035/viewer/2022081801/55141dec550346d8488b56a9/html5/thumbnails/14.jpg)
The slider-crank mechanism Variations of grounding
different links
Inversion D
Window Single Arm
![Page 15: Group A Christopher Back Josephashwin Franklin Kwongvoon Wong Chen Lin Windshield Wiper Soft Top Mechanism](https://reader035.vdocuments.mx/reader035/viewer/2022081801/55141dec550346d8488b56a9/html5/thumbnails/15.jpg)
DOF = 3*(4-1)-2*4= 1
We can imagine that the coupler link length is very small
How is the condition when driver link length change?
Diagram of Rear Wiper
![Page 16: Group A Christopher Back Josephashwin Franklin Kwongvoon Wong Chen Lin Windshield Wiper Soft Top Mechanism](https://reader035.vdocuments.mx/reader035/viewer/2022081801/55141dec550346d8488b56a9/html5/thumbnails/16.jpg)
Flexblade(TM) Wiper .Its life can extend from months to years
The four-bar linkage mechanism will still be used in this wiper system for a long time
![Page 17: Group A Christopher Back Josephashwin Franklin Kwongvoon Wong Chen Lin Windshield Wiper Soft Top Mechanism](https://reader035.vdocuments.mx/reader035/viewer/2022081801/55141dec550346d8488b56a9/html5/thumbnails/17.jpg)
How Windshield Wipers Work. (2006) In: How Stuff Works Available: <http://auto.howstuffworks.com/wiper2.htm> [2007, October 12].
Norton, R.L. Design of Machinery: An Introduction to the Synthesis and Analysis of Mechanisms and Machines. 3rd ed. New York, McGraw-Hill Co. 2006.
How soft top convertible works. (2006) In: How Stuff Works Available: <http://auto.howstuffworks.com/wiper2.htm> [2007, October 12].
Pantographs.(2006) In: Wikipedia The Free Encyclopedia:
<http://en.wikipedia.org/wiki/Pantograph> [2007, October 12].
![Page 18: Group A Christopher Back Josephashwin Franklin Kwongvoon Wong Chen Lin Windshield Wiper Soft Top Mechanism](https://reader035.vdocuments.mx/reader035/viewer/2022081801/55141dec550346d8488b56a9/html5/thumbnails/18.jpg)
• Questions?
![Page 19: Group A Christopher Back Josephashwin Franklin Kwongvoon Wong Chen Lin Windshield Wiper Soft Top Mechanism](https://reader035.vdocuments.mx/reader035/viewer/2022081801/55141dec550346d8488b56a9/html5/thumbnails/19.jpg)
The crank-rocker system will change to be two crank system
![Page 20: Group A Christopher Back Josephashwin Franklin Kwongvoon Wong Chen Lin Windshield Wiper Soft Top Mechanism](https://reader035.vdocuments.mx/reader035/viewer/2022081801/55141dec550346d8488b56a9/html5/thumbnails/20.jpg)
• Contact points in trains
• Linkages on locomotives
• Pushrods mechanism• Car door linkages
![Page 21: Group A Christopher Back Josephashwin Franklin Kwongvoon Wong Chen Lin Windshield Wiper Soft Top Mechanism](https://reader035.vdocuments.mx/reader035/viewer/2022081801/55141dec550346d8488b56a9/html5/thumbnails/21.jpg)
Rear windshield wiper
Single application of
Four-bar mechanism
• Similar to
How is the difference of Rear wiper?