Lecture 28 - Pin Joints, Velcro, Knot Joints, Bridge Joints Notes | EduRev

: Lecture 28 - Pin Joints, Velcro, Knot Joints, Bridge Joints Notes | EduRev

 Page 1


Objectives_template
 Module 8 : Joining 
 Lecture 28 : Pin Joints, Velcro, Knot Joints, Bridge Joints
 
 
The Lecture Contains: 
Pin Joints
Velcro
Knot Joints
Bridge Joints
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
file:///E|/Ayush%20NPTEL%20Course/DESIGN_PARADIGM/lecture28/28_1.htm [2/19/2013 2:45:43 PM]
Page 2


Objectives_template
 Module 8 : Joining 
 Lecture 28 : Pin Joints, Velcro, Knot Joints, Bridge Joints
 
 
The Lecture Contains: 
Pin Joints
Velcro
Knot Joints
Bridge Joints
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
file:///E|/Ayush%20NPTEL%20Course/DESIGN_PARADIGM/lecture28/28_1.htm [2/19/2013 2:45:43 PM]
Objectives_template
 Module 8 : Joining 
 Lecture 28 : Pin Joints, Velcro, Knot Joints, Bridge Joints
 
Pin Joint  
 
Pin Joint is one of the most commonly applied techniques for joining in various products. It is used from 
wooden furniture design and in metal works. It is perhaps the earliest technique that man had invented 
for joining firmly two members together. It behaves like a nail, which would firmly put two things 
together.  
   
Plate 7A Furniture     7B Pin Joints- wood 7C Metal Pin Joints
(Source:http://www.google.co.in/search?q=Universal+Joints&hl=en&prmd=imvns&tbm=isch&tbo=u& 
source=univ&sa=X&ei=BR5UUMqGJpHJrQeuioDYDg&ved=0CDYQsAQ&biw=1332&bih=581#hl=en& 
tbm=isch&sa=1&q=Pin+Joints&oq=Pin+Joints&gs_l=img.12...1007276.1008018.0.1010493.3.3.0.0.0 
.0.0.0..0.0...0.0...1c.1.UiU7pNAwfA4&pbx=1&bav=on.2,or.r_gc.r_pw.r_qf.&fp=507cb4cdb75a83f0&biw 
=1332&bih=581 ; Sept. 15, 2012 
 
From ancient period ‘pin-joint’ has become one of most effective simple joining solutions. In wood 
furniture (plate 7A) usage of wooden-pin for joining two members are most effective. Using metal nail 
for joining woods becomes loose after a few years because of metal rusting and continuous pressure. 
On the other hand it is found that wood-nails (plate 7B) become part of the same material (wood) and 
remains for years. The expansion and contraction because of weather conditions, wood nails 
accommodate the minor changes and remain firm for years. Metal pin-joint (plate 7C) is more effective 
on metal body. 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
file:///E|/Ayush%20NPTEL%20Course/DESIGN_PARADIGM/lecture28/28_2.htm [2/19/2013 2:45:43 PM]
Page 3


Objectives_template
 Module 8 : Joining 
 Lecture 28 : Pin Joints, Velcro, Knot Joints, Bridge Joints
 
 
The Lecture Contains: 
Pin Joints
Velcro
Knot Joints
Bridge Joints
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
file:///E|/Ayush%20NPTEL%20Course/DESIGN_PARADIGM/lecture28/28_1.htm [2/19/2013 2:45:43 PM]
Objectives_template
 Module 8 : Joining 
 Lecture 28 : Pin Joints, Velcro, Knot Joints, Bridge Joints
 
Pin Joint  
 
Pin Joint is one of the most commonly applied techniques for joining in various products. It is used from 
wooden furniture design and in metal works. It is perhaps the earliest technique that man had invented 
for joining firmly two members together. It behaves like a nail, which would firmly put two things 
together.  
   
Plate 7A Furniture     7B Pin Joints- wood 7C Metal Pin Joints
(Source:http://www.google.co.in/search?q=Universal+Joints&hl=en&prmd=imvns&tbm=isch&tbo=u& 
source=univ&sa=X&ei=BR5UUMqGJpHJrQeuioDYDg&ved=0CDYQsAQ&biw=1332&bih=581#hl=en& 
tbm=isch&sa=1&q=Pin+Joints&oq=Pin+Joints&gs_l=img.12...1007276.1008018.0.1010493.3.3.0.0.0 
.0.0.0..0.0...0.0...1c.1.UiU7pNAwfA4&pbx=1&bav=on.2,or.r_gc.r_pw.r_qf.&fp=507cb4cdb75a83f0&biw 
=1332&bih=581 ; Sept. 15, 2012 
 
From ancient period ‘pin-joint’ has become one of most effective simple joining solutions. In wood 
furniture (plate 7A) usage of wooden-pin for joining two members are most effective. Using metal nail 
for joining woods becomes loose after a few years because of metal rusting and continuous pressure. 
On the other hand it is found that wood-nails (plate 7B) become part of the same material (wood) and 
remains for years. The expansion and contraction because of weather conditions, wood nails 
accommodate the minor changes and remain firm for years. Metal pin-joint (plate 7C) is more effective 
on metal body. 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
file:///E|/Ayush%20NPTEL%20Course/DESIGN_PARADIGM/lecture28/28_2.htm [2/19/2013 2:45:43 PM]
Objectives_template
 Module 8 : Joining                      
 Lecture 28 : Pin Joints, Velcro, Knot Joints, Bridge Joints
 
Velcro
  
Plate 8A Burdock Plant   8B Hooked seed of Burdock seed 
(Source:http://www.google.co.in/search?q=Burdock+plant&hl=en&prmd=imvns&tbm= 
isch&tbo=u&source=univ&sa=X&ei=ZZZUUJaQJ8PqrAe63oDICw&ved=0CB8QsAQ& 
biw=1332&bih=581 ; Sept. 15, 2012)
Burdock Plant (plate 8A) in nature has similar characteristic that sticks to another surface and move 
from one place to another for germination. Usually Burdock seeds (plate 8B) are carried by animal. A 
Swiss engineer found the inspiration of inventing Velcro accidentally. “The hook-and-loop fastener was 
conceived in 1941 by Swiss engineer, Georges de Mestral who lived in Switzerland. The idea came to 
him one day after returning from a hunting trip with his dog in the Alps. He took a close look at the burrs 
(seeds) of burdock that kept sticking to his clothes and his dog's fur. He examined them under a 
microscope, and noted their hundreds of "hooks" that caught on anything with a loop, such as clothing, 
animal fur, or hair. He saw the possibility of binding two materials reversibly in a simple fashion if he 
could figure out how to duplicate the hooks and loops.” 
(Ref. http://en.wikipedia.org/wiki/Velcro ; Sept. 15, 2012
Plate 9A Velcro  
  
  9B Shoe Strap  
9C Watch 
Strap  
9D Hand strap 9E Cover
 
 
 
 
 
 
 
 
 
 
 
 
 
 
file:///E|/Ayush%20NPTEL%20Course/DESIGN_PARADIGM/lecture28/28_3.htm [2/19/2013 2:45:43 PM]
Page 4


Objectives_template
 Module 8 : Joining 
 Lecture 28 : Pin Joints, Velcro, Knot Joints, Bridge Joints
 
 
The Lecture Contains: 
Pin Joints
Velcro
Knot Joints
Bridge Joints
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
file:///E|/Ayush%20NPTEL%20Course/DESIGN_PARADIGM/lecture28/28_1.htm [2/19/2013 2:45:43 PM]
Objectives_template
 Module 8 : Joining 
 Lecture 28 : Pin Joints, Velcro, Knot Joints, Bridge Joints
 
Pin Joint  
 
Pin Joint is one of the most commonly applied techniques for joining in various products. It is used from 
wooden furniture design and in metal works. It is perhaps the earliest technique that man had invented 
for joining firmly two members together. It behaves like a nail, which would firmly put two things 
together.  
   
Plate 7A Furniture     7B Pin Joints- wood 7C Metal Pin Joints
(Source:http://www.google.co.in/search?q=Universal+Joints&hl=en&prmd=imvns&tbm=isch&tbo=u& 
source=univ&sa=X&ei=BR5UUMqGJpHJrQeuioDYDg&ved=0CDYQsAQ&biw=1332&bih=581#hl=en& 
tbm=isch&sa=1&q=Pin+Joints&oq=Pin+Joints&gs_l=img.12...1007276.1008018.0.1010493.3.3.0.0.0 
.0.0.0..0.0...0.0...1c.1.UiU7pNAwfA4&pbx=1&bav=on.2,or.r_gc.r_pw.r_qf.&fp=507cb4cdb75a83f0&biw 
=1332&bih=581 ; Sept. 15, 2012 
 
From ancient period ‘pin-joint’ has become one of most effective simple joining solutions. In wood 
furniture (plate 7A) usage of wooden-pin for joining two members are most effective. Using metal nail 
for joining woods becomes loose after a few years because of metal rusting and continuous pressure. 
On the other hand it is found that wood-nails (plate 7B) become part of the same material (wood) and 
remains for years. The expansion and contraction because of weather conditions, wood nails 
accommodate the minor changes and remain firm for years. Metal pin-joint (plate 7C) is more effective 
on metal body. 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
file:///E|/Ayush%20NPTEL%20Course/DESIGN_PARADIGM/lecture28/28_2.htm [2/19/2013 2:45:43 PM]
Objectives_template
 Module 8 : Joining                      
 Lecture 28 : Pin Joints, Velcro, Knot Joints, Bridge Joints
 
Velcro
  
Plate 8A Burdock Plant   8B Hooked seed of Burdock seed 
(Source:http://www.google.co.in/search?q=Burdock+plant&hl=en&prmd=imvns&tbm= 
isch&tbo=u&source=univ&sa=X&ei=ZZZUUJaQJ8PqrAe63oDICw&ved=0CB8QsAQ& 
biw=1332&bih=581 ; Sept. 15, 2012)
Burdock Plant (plate 8A) in nature has similar characteristic that sticks to another surface and move 
from one place to another for germination. Usually Burdock seeds (plate 8B) are carried by animal. A 
Swiss engineer found the inspiration of inventing Velcro accidentally. “The hook-and-loop fastener was 
conceived in 1941 by Swiss engineer, Georges de Mestral who lived in Switzerland. The idea came to 
him one day after returning from a hunting trip with his dog in the Alps. He took a close look at the burrs 
(seeds) of burdock that kept sticking to his clothes and his dog's fur. He examined them under a 
microscope, and noted their hundreds of "hooks" that caught on anything with a loop, such as clothing, 
animal fur, or hair. He saw the possibility of binding two materials reversibly in a simple fashion if he 
could figure out how to duplicate the hooks and loops.” 
(Ref. http://en.wikipedia.org/wiki/Velcro ; Sept. 15, 2012
Plate 9A Velcro  
  
  9B Shoe Strap  
9C Watch 
Strap  
9D Hand strap 9E Cover
 
 
 
 
 
 
 
 
 
 
 
 
 
 
file:///E|/Ayush%20NPTEL%20Course/DESIGN_PARADIGM/lecture28/28_3.htm [2/19/2013 2:45:43 PM]
Objectives_template
 Module 8 : Joining                        
 Lecture 28 : Pin Joints, Velcro, Knot Joints, Bridge Joints
 
(Source: http://www.google.co.in/search?hl=en&q=Velcro&bav=on.2,or.r_gc.r_pw.r_qf.&biw 
=1332&bih=581&um=1&ie=UTF-8&tbm=isch&source=og&sa=N&tab=wi&ei=QJhUUOawDM 
fMrQfLioCgCQ#um=1&hl=en&tbm=isch&sa=1&q=Velcro+Child+products&oq=Velcro+Child 
+products&gs_l=img.12...118360.125903.2.127978.14.13.0.0.0.0.0.0..0.0.eesh..0.0...1.1.g0 
yMQ2xY0zc&pbx=1&bav=on.2,or.r_gc.r_pw.r_qf.&fp=c9d326b109e25994&biw=1332&bih= 
581 ; Sept. 15, 2012)
Thus, nature’s paradigm inspired man to invent a mechanism that has almost become synonymous to 
stitching or joining to flexible material. Velcro (plate 9A) is a mechanism that hooks and loop fastener 
between two surfaces. One hooks and the other with the loops. When the hooks are placed on the 
loops they join together. In nature Burdock works in the same mechanism. It is used in binding almost 
everything from fastening shoes, hanging photos and even securing cables in computers and space 
shuttles. Application of Velcro is commonly found in sports shoes (plate 9B) that would have easy 
opening and tightening. Velcro has helped to tighten hand-strap (plate 9C&D) much easily compare to 
knot or buckle. To open faster and closing the upper cover (plate 9E) Velcro has become much effective. 
 
Knot Joints 
Plate 10A Rope 
Knots
10B Locking 
Knots
10C Jewellery 10D Tussle   
10E Knot 
Hairstyle 
(Source:http://www.google.co.in/search?hl=en&q=Knots+in+Product+Design&bav=on.2,or.r 
_gc.r_pw.r_qf.&biw=1332&bih=581&um=1&ie=UTF-8&tbm=isch&source=og&sa=N&tab=wi& 
ei=LFtVUIKqCcrtrQeF1IHQDg ; Sept. 16, 2012)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
file:///E|/Ayush%20NPTEL%20Course/DESIGN_PARADIGM/lecture28/28_4.htm [2/19/2013 2:45:44 PM]
Page 5


Objectives_template
 Module 8 : Joining 
 Lecture 28 : Pin Joints, Velcro, Knot Joints, Bridge Joints
 
 
The Lecture Contains: 
Pin Joints
Velcro
Knot Joints
Bridge Joints
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
file:///E|/Ayush%20NPTEL%20Course/DESIGN_PARADIGM/lecture28/28_1.htm [2/19/2013 2:45:43 PM]
Objectives_template
 Module 8 : Joining 
 Lecture 28 : Pin Joints, Velcro, Knot Joints, Bridge Joints
 
Pin Joint  
 
Pin Joint is one of the most commonly applied techniques for joining in various products. It is used from 
wooden furniture design and in metal works. It is perhaps the earliest technique that man had invented 
for joining firmly two members together. It behaves like a nail, which would firmly put two things 
together.  
   
Plate 7A Furniture     7B Pin Joints- wood 7C Metal Pin Joints
(Source:http://www.google.co.in/search?q=Universal+Joints&hl=en&prmd=imvns&tbm=isch&tbo=u& 
source=univ&sa=X&ei=BR5UUMqGJpHJrQeuioDYDg&ved=0CDYQsAQ&biw=1332&bih=581#hl=en& 
tbm=isch&sa=1&q=Pin+Joints&oq=Pin+Joints&gs_l=img.12...1007276.1008018.0.1010493.3.3.0.0.0 
.0.0.0..0.0...0.0...1c.1.UiU7pNAwfA4&pbx=1&bav=on.2,or.r_gc.r_pw.r_qf.&fp=507cb4cdb75a83f0&biw 
=1332&bih=581 ; Sept. 15, 2012 
 
From ancient period ‘pin-joint’ has become one of most effective simple joining solutions. In wood 
furniture (plate 7A) usage of wooden-pin for joining two members are most effective. Using metal nail 
for joining woods becomes loose after a few years because of metal rusting and continuous pressure. 
On the other hand it is found that wood-nails (plate 7B) become part of the same material (wood) and 
remains for years. The expansion and contraction because of weather conditions, wood nails 
accommodate the minor changes and remain firm for years. Metal pin-joint (plate 7C) is more effective 
on metal body. 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
file:///E|/Ayush%20NPTEL%20Course/DESIGN_PARADIGM/lecture28/28_2.htm [2/19/2013 2:45:43 PM]
Objectives_template
 Module 8 : Joining                      
 Lecture 28 : Pin Joints, Velcro, Knot Joints, Bridge Joints
 
Velcro
  
Plate 8A Burdock Plant   8B Hooked seed of Burdock seed 
(Source:http://www.google.co.in/search?q=Burdock+plant&hl=en&prmd=imvns&tbm= 
isch&tbo=u&source=univ&sa=X&ei=ZZZUUJaQJ8PqrAe63oDICw&ved=0CB8QsAQ& 
biw=1332&bih=581 ; Sept. 15, 2012)
Burdock Plant (plate 8A) in nature has similar characteristic that sticks to another surface and move 
from one place to another for germination. Usually Burdock seeds (plate 8B) are carried by animal. A 
Swiss engineer found the inspiration of inventing Velcro accidentally. “The hook-and-loop fastener was 
conceived in 1941 by Swiss engineer, Georges de Mestral who lived in Switzerland. The idea came to 
him one day after returning from a hunting trip with his dog in the Alps. He took a close look at the burrs 
(seeds) of burdock that kept sticking to his clothes and his dog's fur. He examined them under a 
microscope, and noted their hundreds of "hooks" that caught on anything with a loop, such as clothing, 
animal fur, or hair. He saw the possibility of binding two materials reversibly in a simple fashion if he 
could figure out how to duplicate the hooks and loops.” 
(Ref. http://en.wikipedia.org/wiki/Velcro ; Sept. 15, 2012
Plate 9A Velcro  
  
  9B Shoe Strap  
9C Watch 
Strap  
9D Hand strap 9E Cover
 
 
 
 
 
 
 
 
 
 
 
 
 
 
file:///E|/Ayush%20NPTEL%20Course/DESIGN_PARADIGM/lecture28/28_3.htm [2/19/2013 2:45:43 PM]
Objectives_template
 Module 8 : Joining                        
 Lecture 28 : Pin Joints, Velcro, Knot Joints, Bridge Joints
 
(Source: http://www.google.co.in/search?hl=en&q=Velcro&bav=on.2,or.r_gc.r_pw.r_qf.&biw 
=1332&bih=581&um=1&ie=UTF-8&tbm=isch&source=og&sa=N&tab=wi&ei=QJhUUOawDM 
fMrQfLioCgCQ#um=1&hl=en&tbm=isch&sa=1&q=Velcro+Child+products&oq=Velcro+Child 
+products&gs_l=img.12...118360.125903.2.127978.14.13.0.0.0.0.0.0..0.0.eesh..0.0...1.1.g0 
yMQ2xY0zc&pbx=1&bav=on.2,or.r_gc.r_pw.r_qf.&fp=c9d326b109e25994&biw=1332&bih= 
581 ; Sept. 15, 2012)
Thus, nature’s paradigm inspired man to invent a mechanism that has almost become synonymous to 
stitching or joining to flexible material. Velcro (plate 9A) is a mechanism that hooks and loop fastener 
between two surfaces. One hooks and the other with the loops. When the hooks are placed on the 
loops they join together. In nature Burdock works in the same mechanism. It is used in binding almost 
everything from fastening shoes, hanging photos and even securing cables in computers and space 
shuttles. Application of Velcro is commonly found in sports shoes (plate 9B) that would have easy 
opening and tightening. Velcro has helped to tighten hand-strap (plate 9C&D) much easily compare to 
knot or buckle. To open faster and closing the upper cover (plate 9E) Velcro has become much effective. 
 
Knot Joints 
Plate 10A Rope 
Knots
10B Locking 
Knots
10C Jewellery 10D Tussle   
10E Knot 
Hairstyle 
(Source:http://www.google.co.in/search?hl=en&q=Knots+in+Product+Design&bav=on.2,or.r 
_gc.r_pw.r_qf.&biw=1332&bih=581&um=1&ie=UTF-8&tbm=isch&source=og&sa=N&tab=wi& 
ei=LFtVUIKqCcrtrQeF1IHQDg ; Sept. 16, 2012)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
file:///E|/Ayush%20NPTEL%20Course/DESIGN_PARADIGM/lecture28/28_4.htm [2/19/2013 2:45:44 PM]
Objectives_template
 Module 8 : Joining                        
 Lecture 28 : Pin Joints, Velcro, Knot Joints, Bridge Joints 
 
Knot (plate 10A) joints are commonly applied for rope, thread and flexible material. Knot is to tie two 
ends firmly so that they do not separate. Rock climbing and mountaineering has to use extensive knots 
for safer climbing. Knot uses such technique so that with greater force from opposite directions the knot 
becomes stronger. However, knots have varieties of applications depending on the purpose- security, 
fashion, decorative, safety, etc. Nylon plastic knots (plate 10B) are used for securing cable to locking 
flight baggage. Designers use attractive knots in jewellery design (plate 10C). Use of tussles (plate 10D) 
is part of decoration is found from early period. Royal robes and military decoration with tussles are part 
of the dress code. Hairstyle (plate 10E) with knots is part of style in fashion design. Thus, each time 
knot displays its manifestation is part of joining paradigm. 
 
Bridging  
 
Joining two separate lands by building bridge is a long tradition from ancient time. Bridge may be 
constructed with variety of materials- brick, stone, rope, bamboo, metal, cable, etc. 
Plate 11A Harbour 
Bridge
11B Stone Bridge      11C Bamboo Bridge 11D Brick & Stone Bridge
Sydney      Mughal Period     Japan     Jabalpur, India
(Source:http://www.google.co.in/search?hl=en&q=Knots+in+Product+Design&bav=on.2,or.r_gc.r_ 
pw.r_qf.&biw=1332&bih=581&um=1&ie=UTF8&tbm=isch&source=og&sa=N&tab=wi&ei=LFtVUIK 
qCcrtrQeF1IHQDg#um=1&hl=en&tbm=isch&sa=1&q=Bridge+&oq=Bridge+&gs_l=img.12...2948. 
8538.3.10205.9.9.0.0.0.0.0.0..0.0...0.0...1c.1.Obniz3kXP08&pbx=1&bav=on.2,or.r_gc.r_pw.r_qf. 
&fp=714eab418a8040b9&biw=1332&bih=581 ; Sept. 16, 2012)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
file:///E|/Ayush%20NPTEL%20Course/DESIGN_PARADIGM/lecture28/28_5.htm [2/19/2013 2:45:44 PM]
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