Design and Development of an Impact Attenuator

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Table Of Contents

LITERATURE REVIEW ON CARBON FIBER1

DESIGN REVIEW OF CARBON FIBER2

MATERIAL LIST4

INTRUSION PLATE4

CARBON FIBER PANELS HOW MANY LAYERS ETC10

METHODOLOGY11

PRELIMINARY TESTING12

CARBON FIBRE IMPACT ATTENUATOR12

STURCTURE BUILDING13

DISCUSSION15

DESIGN TASKS/ SPECS15

Deceleration17

High Speed Camera17

Weighted Drop17

Hydraulic Testing18

Rolling Cart Test18

Swinging Pendulum Test18

DESIGN ANALYSIS19

Design Selection19

HONEYCOMB PYRAMID SOLID MODEL20

SUMMARY23

Materials25

Design25

Impact Testing26

REFERENCES28

Design and Development of an Impact Attenuator

An introduction

Literature review on carbon fiber

Carbon fiber is a super strong material that's also extremely lightweight. Engineers and designers love it because it's five times as strong as steel, two times as stiff, yet weighs about two-thirds less. Carbon fiber is basically very thin strands of carbon -- even thinner than human hair. The strands can be twisted together, like yarn. The yarns can be woven together, like cloth. To make carbon fiber take on a permanent shape, it can be laid over a mold, then coated with a stiff resin or plastic (kind of like how you would make something out of papier-mâché by putting newspaper strips over a mold, then adding paste to force it to hold the shape).

Most car components are made of steel. Replacing steel components with carbon fiber would reduce the weight of most cars by 60 percent. That 60 percent drop in weight would, in turn, reduce that car's fuel consumption by 30 percent and cut greenhouse gas and other emissions by 10 to 20 percent. That's a huge fuel savings, even without changing the car's engine. With a lighter carbon fiber body, car makers could build cars with smaller, more efficient engines, or increase the use of electric engines, resulting in even more fuel savings. Reducing weight, increasing fuel efficiency and allowing for the development of different kinds of engines: That's how carbon fiber can solve the oil crisis.

Carbon Fibre, not surprisingly, is made of carbon crystals aligned in the long axis. These honeycomb shaped crystals organize themselves in long flattened ribbons. This crystal alignment makes the fiber strong. These ribbons are formed within long fibers. The fiber shape is the original shape of the material used to produce the Carbon Fiber. I don't know of any process where fibers are shaped AFTER carbonizing. These fibers in turn are bundled in large numbers and are woven, made into felt, twisted or as bundled without twisting. This is referred to as Roving. Carbon fiber is also offered as chopped strands and powder.In order to modify the characteristics of the lay up, other materials are sometimes added such as glass fibers, Kevlar or Aluminium. Carbon fiber is rarely used as it. Rather it is imbedded in a matrix. In mastmaking and boat building we usually think of epoxy or polyester resins, but carbon fiber is used in thermoplastics, concrete or ceramics.

There are several methods of making carbon fiber but essentially it consists of carbonizing and stretching precursor fibers, either PAN: Polyacrylonitrile, Pitch or Rayon. There are several cycles of heating at varying temperatures excluding oxygen. This process drives off most of other elements of the starting material leaving carbon ...