Capstone Report On Wheel Chair Cum Stretcher

DESIGN AND FABRICATION OF A MULTI PURPOSE WHEEL CHAIR CUM STRETCHER Capstone Project Submitted in Fulfillment of the Requirement for Award of the Degree Of

BACHELOR OF TECHNOLOGY In MECHANICAL ENGINEERING By MOPARTHI RAKESH

(11602966)

POREDDY SAI CHARAN REDDY

(11611779)

NITTALA PRANAV

(11602701)

HARSH RAKWAL

(11402102)

Under the Guidance of SHAILJA KANDWAL

DEPARTMENT OF MECHANICAL ENGINEERING LOVELY PROFESSIONAL UNIVERSITY PHAGWARA, PUNJAB (INDIA) -144402 2019-20

Lovely Professional University Jalandhar, Punjab

CERTIFICATE I hereby certify that the work which is being presented in the capstone entitled “Design and fabrication of a multipurpose wheelchair cum stretcher” in partial fulfillment of the requirement for the award of degree of Bachelor of Technology and submitted in Department of Mechanical Engineering, Lovely Professional University, Punjab is an authentic record of my own work carried out during period of Capstone under the supervision of Shailja kandwal Department of Mechanical Engineering, Lovely Professional University, Punjab. The matter presented in this capstone has not been submitted by me anywhere for the award of any other degree or to any other institute. Date:

. Moparthi Rakesh Poreddy Sai Charan Reddy Nittala Pranav Harsh Rakwal (name of the students)

This is to certify that the above statement made by the candidate is correct to best of my knowledge Date:

(Shailja Kandwal) Supervisor

The B- Tech capstone examination of ABC, has been held on _____________

Signature of Examiner

DECLARATION We, students of B.Tech under Department of Mechanical Engineering of Lovely Professional University, Punjab, hereby declare that all the information furnished in this project report is our own study and is genuine. This project does not, to the best of my knowledge, contain part of my work which has been submitted for the award of my degree either of this university or any other university without proper citation.

Date:

Signature of Candidates

MOPARTHI RAKESH

(11602966)

POREDDY SAI CHARAN REDDY

(11611779)

NITTALA PRANAV

(11602701)

HARSH RAKWAL

(11402102)

TABLE OF CONTENTS

CHAPTER 1............................................................................................................08 INTRODUCTION...................................................................................................08 1.1 Types of disability…….....................................................................................08 1.2 Physical disability .............................................................................................09 1.3 Sensor disability ...............................................................................................09 1.4 Mobility aid………………………………………….......................................09 1.5 Problem definition …………………………………………………………….10 1.6 Project scope…………………………………………......................................10 C HAP T ER 2 …… … ……… …… ……… … … …… …… ……… … … … .…… ……11 LITERATURE REVIEW.........................................................................................11 2.1 Research and Development.................................................................................11 2.2 Reference Publications and Projects................................................................11 2.3 Wheel chair.....................................................................................................12 2.4 Types of Wheel chair.......................................................................................14 2.5 Stretcher..............................................................................................................17 2.6 Types of stretcher...............................................................................................17 2.7 Theme board......................................................................................................18 2.8 concepts................................................................................................................19 2.9 concept selection....................................................................................................20

CHAPTER 3 .............................................................................................................21 SCOPE OF STUDY AND OBJECTIVE...................................................................21 3.1 Scope....................................................................................................................21 3.2 Objectives ............................................................................................................21 CHAPTER 4...............................................................................................................22 RESEARCH METHODOLOGY................................................................................22 4.1 Wheelchair International Standards......................................................................22 4.2 Base strcuture..........................................................................................................23

4.3 Rear wheels............................................................................................................23 4.4 casters.......................................................................................................................24 4.5 Main base structure.................................................................................................25 4.6 Bearings ..................................................................................................................25

CHAPTER 5 .................................................................................................................26 WORK PLANNING .....................................................................................................26 5.1 Planning and Processing .........................................................................................26 5.2 Brainstorming Structure Design ..............................................................................26 5.3 Manufacturing Strategies and Materials ..................................................................26 5.4 Prototype and Design Approval ...............................................................................27 5.5 Purchase and Market Survey ....................................................................................27 5.6 Testing and Checking Dimensions ...........................................................................27 5.7 Assembly...................................................................................................................27 5.8 Tabulated Work Plan ................................................................................................28 CHAPTER 6 ...................................................................................................................29 DETAIL DESIGN..............................................................................................................29 6.1 Design...........................................................................................................................29

CHAPTER 7...................................................................................................................29 TECHNICAL DETAILS OF THE SETUP ....................................................................31 7.1 Planetary And Machine Required..............................................................................31 7.2 Material used .............................................................................................................33 7.3 Factors determining choice of material .....................................................................36

CHAPTER 8.............................................................................................................................39 CONCLUSION...................................................................................................................39

CHAPTER 9 ..................................................................................................................40 REFERENCES.................................................................................................................40

LIST OF FIGURES

Figure Name

Page no.

1.1

Physical disability…………………………………………………………… 09

1.2

Sensor disability………………………………………………………………. 09

2.1

Wheel chair…………………………………………………………………… 13

2.2

History of wheel chair………………………………………………………14

2.3

Types of wheelchair…………………………………………………………15

2.4

Sports wheelchairs……………………………………………………………16

2.5

Stretcher……………………………………………………………………17

2.6

Theme board………………………………………………………………18

2.7

Concepts……………………………………………………………………19

2.8

Concept Selection……………………………………………………………..20

4.1

Wheel chair standards………………………………………………………...22

4.2

Rear wheels……………………………………………………………. 23

4.3

Front caster wheel…………………………....……………………………… 24

5.1

Planning and processing…………………………………………………….. 26

6.1

Design view of stretcher………………………………………………………29

6.2

Design view of wheel chair……………………………………………………30

7.1

Lathe machine………………………………...……………………………. 31

7.2

Drilling machine……………………………………………………………… 32

7.3

Welding machine……………………………...……………………………… 32

LIST OF TABLES Table

Name

page no

5.1

Work plan……………………………………………………………………28

7.1

Chemical Composition………………………………………………………...33

7.2

Physical Properties…………………………………………………………….33

7.3

Mechanical properties………………………………………………………..34

7.4

Material used…………………………………………………………………37

ABSTRACT The major aim of the capstone project is to harness the technical knowledge incurred by us while pursuing the degree and effectively drive it into the practical endeavour. This project also leverages the competent skills of students like Team-work, Hard-work, Time management, Meeting Deadliness and Sincerity. This project deals with the work done by our team over a period of four months. People suffering a lot from moving from wheel chair to stretcher thus our project of changeable wheel chair cum stretcher is used for them.

CHAPTER 1 INTRODUCTION DISABILITY is the term that is in use from so many decades . As per Oxford Etymology, “DISABILITY” is used in many contexts , In 1650’s it was a sport with the name “CAP IN HAND”, In 1750’s it was used in horse races , In 1870’s it is regarded as “Any race or competition in which the chances of the competitors are to be equalized by giving an advantage to the less efficient one or imposing a disadvantage upon the more efficient one .”. From the year 1915 the word “DISABILITY/HANDICAP” has become the brand name for the people who are physically or mentally challenged. “Disabilities is a term, covering impairments, activity limitations, and participation restrictions. An impairment is defined as a problem in the body function or structure; an activity limitation is a difficulty encountered by an individual in executing a task or action; while a participation restriction is a problem experienced by an individual in involvement in the life situations. Thus, disability is a complex phenomenon as it is reflecting an interaction between features of a person’s body and features of the society in which she or he lives”

World Health Organization 1.1 Types of Disabilities : Disability is caused by impairments to various subsystems of the body. Disabilities are classified into different categories. 1. Physical Disabilities 2. Sensory Disabilities a. Visual Impairment b. Hearing Impairment c. Olfactory and gustatory Impairment d. Somatosensory Impairment 3. Intellectual Disabilities 4. Mental health and emotional disabilities

1.2 Physical Disabilities

Fig 1.1 1.3 Sensory Disabilities

Fig 1.2 1.4 MOBILITY AID: Mobility aid is defined as a device which was designed to help disabled walk or to improve the mobility or movement for the people having impairments. There are several walking aids that are available which are helping the impaired to walk and wheelchairs or mobility type of scooters are used for more severe disabilities or for the impaired people doing long journeys., For blind or visually disabled people , white cane and guide dog are being in use from a long time. Traditionally (before) "mobility aid" is been applied to the mechanical devices that have low technology.

The different types of Mobility Aids: 1. Walking aids that will help disabled to walk a. Canes b. Crutches c. Canes & crutches combination d. Canes & forearm crutch combinations e. Walkers f.

Hybrid Walkers

2. Wheelchairs and Scooters 3. Stair lifts 4. Others a. Sling lifts b. Lift chairs c. Knee scooters

1.5 PROBLEM DEFINITION The patients or disabled people are getting increased day by day in India. In hospitals the patient needs to get shifted from wheel chair to stretcher, stretcher to beds, bed to wheelchair, or vice versa; that creates pain and suffering for the injured patients. Transferring or shifting of the patients in the hospitals is a common problem for caretakers or nurses. 1.6 PROJECT SCOPE This project Proposes a design that will reduce the effort being kept by caretaker and it will also provide safe shifting of the patients in hospitals or other places and to make it comfortable for disabled people. Hence is can be used for both function.

CHAPTER 2 LITRATURE REVIEW It is very important and essential for having sufficient information to start a research work and carry it in proper direction. Any further improvement and modification in a particular field always needed its history, accurate data, result and their analysis.

2.1 RESEARCH AND DEVELOPMENT Here are some of the important research documents that have been published on our topic wheel chair cum stretcher.

2.2 REFERENCE PUBLICATIONS AND PROJECTS 1. Design and Fabrication of Multiutility Wheelchair by Sandip S Bag, Prem D Lohe, Harshal K International Journal 3, 182-188, 2017 The main purpose of the article is to discuss about the uses of wheel chair and to study about it design and its components .From this article we are able to know how the wheel chair cum stretcher is used to disabled people ,people in hospitals while shifting to bed. It also tell us about the forces acting on the wheelchair cum stretcher and materials, components to be required to construct the wheel chair cum stretcher. 2. How many people may benefit from a smart or highly technological wheelchair? By Richard Simpson So before starting the project it was necessary for us see how useful this product would be and how many people would need it, from the above paper we found our required answer, this paper funded by the U.S. Department of Veterans Affairs, gives the exact number of people who would use such a device. To obtain the set result, they collected information about number of people suffering from set disease, and the percentage of people that would actually be needing a smart chair. Though the results collected relate to the USA, we could see the potential of our product and thus justify the time we put into it. Current Directions in Wheelchair Research by Colin A. McLaurin, ScD

In this paper Mr. McLaurin, performs an intensive study on wheelchairs, he says that wheelchair has become a symbol of disability, and it is highlighted as the symbol of

handicapped. He also said that this is one of the main reason that students, professors, inventors and researchers are doing a lot of study in the recent years on wheelchairs and other accepts related to it.

The paper individually highlights different departments within a wheelchair where the research is being done, first are Functional Characteristics, under this have Seating Comfort and Support, and Mobility. He has provided study on different diseases and given the data such as Seating height, Seating angle, Angle of seat to horizontal, Angle of back to horizontal. Such data is very useful when the main requirement is to provide customer satisfaction.

He then goes into study on each and every component that effects the performance of a manual wheelchair, Frame, a tubular structure has been mostly being used a lot for a long time now and materials of aluminium alloy, titanium and have different characteristics and that each, simple stress analysis on a computer software can be done to find out is strengths and weaknesses, before proceeding for the design.

Seats, much of research has not been done in this area but, a rigid cushion is used because it can provide with a comfortable and predictable support can be provided. Light weight and adjustable seating systems, these allow to be customized by the customer to adjust to his comfortable position and large amount of research is being done on this to provide a correct material, design and reliability of such designs. Many companies provide such designs and some are very complex, so a high reliability is important to provide a long term of useful time and keep the occupant safe and comfortable.

2.3 WHEELCHAIR Wheelchairs were in use from more than 100 years, but old wheelchairs were only to help the disabled or patient to move from one place to another place. As society is developing and changing the wheelchairs also got changed because the disabled individuals became more integrated, the role of the wheelchair also got changed. Wheelchairs are directly seen as a techniques for transportation just as a way to deal with empower the users to express their uniqueness.

In year 1950, the first powered wheelchair was developed and It had used a electric motor to power wheelchair. At the same time the sports wheelchairs came to existence. In year 1964, first Paralympics games (also called as games for disabled people) were held in Tokyo, Japan. Modern day wheelchairs are needed to be made up of light materials and have high technology to meet the requirements of people. The wheelchairs available should meet the needs and desires of the people or human. The future expects a well developed and highly technological wheelchair that could help to serve the needy. The basic structure of wheelchair has various parts. In simple words it is nothing but a set of wheels attached to the chair. some of the important things a wheelchair must contain are as follows. The seat should be comfortable, so that user or disabled patient does not feel tired if he is sitting on it for long duration. It need to have a backrest which provides good back support. It should also have arm rest at an optimum height to keep arms and a also a foot rest for legs.

Fig 2.1 Wheel chair

Since the birth of wheelchair, there have been many modifications to its design. Today there exists a huge variety of wheelchairs- manually, electric, foldable or rigid. Apart from these they are classified based on their usage, standing wheelchair, sports wheelchair, mobility scooters, bathroom wheelchair, steps climbing wheelchair etc. The range of wheelchairs reflects the demand to meet individual needs.

Fig 2.2 History of wheel chair 2.4 TYPES OF WHEELCHAIRS Some type of wheel chairs are discussed below… Manual wheelchairs Manual wheelchairs are the type of wheel chairs that are moved by the user or by any other person. By the use of push rims, users may travel frontwards and backwards at speeds based on the amount of the force applied and it will allow to go towards left or right side. Manual Transit wheelchairs These type of wheel chairs are having small rear wheels and these don’t have push rims. These wheelchairs are seen in places like airports and hospitals where attendants are there to carry. They were also termed as manual transfer wheelchairs.

Fig 2.3 Types of wheel chair

Electric wheelchairs Electric wheelchairs are also called “motorized wheelchairs” and sometimes electric powered wheelchairs are powered by using electric motor. These chairs are used to navigate using the control systems. For the individuals who are too feeble to even think about moving, a manually power controlled wheelchair will profoundly profit by , additionally the people having heart and breathing issues..

Wheelbase A wheelbase chair, also known as a scooter, consists of four small wheels. The sort of chair mounted in this differs as indicated by the kind of incapacity and requirements of the user or individual ; The controls of the wheelbase seat are mounted on a casing that bends upward from the front to a tallness and position that is helpful for the client. A level guiding bar is joined to the highest point of the casing.

Sports chairs Since the year 1970, the crippled athletic people are utilizing the particular wheelchairs to assist them with accomplishing their objectives from their preferred game. These seats appears to be unique from one another, however what's basic in them is their lightweight casings made up utilizing composite material; having robustness and steadiness for unexpected turns (for this we utilize calculated wheels).Sports wheelchairs are exceptionally intended for competitors with handicaps who are contending in the games, for example, ball, athletic, tennis.

Fig 2.4 Sports wheelchairs Stand-up Stand-up wheelchairs contains pressure driven hydraulic pump that lifts and tilts the seat, it will assist the userwith standing "up" independent from anyone else yet he is completely upheld by the seat. This is helpful component if the client needs to take a thing from a rack or on the off chance that he need to go out to do any shopping Stair-climbing wheelchairs Climbing stairs is one of the useful and innovative wheelchair. It is battery operated that will support it’s back end so it acts as stabilisers on climbing using the chair. It has a series of flexible wheels which will help to turn the rubber tracks so that it can grip the steps.

2.5 STRETCHER A stretcher is defined as a medical device which is used for carry or movement the affected people or patients for some short period of time. A stretcher contains a surface that help for conveying patients, and it has handles on either side along its length to help convey it. Stretchers have been utilized since numerous years. They are utilized on war zones before to convey harmed individuals in the war. Today, there are a wide scope of stretchers are available that are comprised of lightweight materials and connections

Fig 2.7 Stretcher

2.6 TYPES OF STRETCHERS Some of the types of stretchers are explained below: Basket stretcher A basket stretcher is used in situation when an injured person needs transportation by foot to go to the medical attention. This type of stretcher disassembles in 2 halves, and when needed for rescue or operation it will get assembled in seconds. Ambulance stretcher An ambulance stretcher, known as a little or gurney, consists of a solid frame and a heavyduty cloth that stretches across it. This ambulance often give the user a rough ride. This type of stretcher also a absorbs part of impact to prevent any further injury.

Folding stretchers Folding stretcher is used for transporting the injured ones from the inside of a building to an ambulance stretcher. It’s portable and it can be folded into half for a convenient storage. This stretcher is likewise a light weight one and is easy to carry and it is made of high strength materials. These are accessible in various sizes to fit for various individuals dependent on their size. Pole Stretcher The military people mostly use these type of stretchers to transport or take away the wounded or injured people to a nearest medical facility. This type has a heavy-duty poles that extend on both sides so two men will carry it. They are in lightweight and have firm control while handling.

2.7 THEME BOARD

Fig 2.6 Theme board

2.8 CONCEPTS

Fig 2.7 Concepts

2.9 CONCEPT SELECTION Various concepts were generated and selection was based on a matrix comparison involving all the concepts and some parameters. CONCEPT :Based on the selection some refinements were made.

Figure 2. : concept selection Above Fig shows the folding mechanism of product which we were designed. “Link 1” is for back rest, “link 2” is the seating area , “link 3” is for the leg support. “Link a” is mutually perpendicular to “link 1” and “link e” is mutually perpendicular to “link 3”. “Link c” is a ball screw which moves linearly to and fro like a pendulum which is shown as dotted line in the fig. “Link e” and “link a” are connected to “link c” by other links b and d respectively. Red color arrow indicates the ball screw displacing to the right side of the viewer upon which the product will become as a stretcher and this conversion is only done when the entire platform is raised to desired position. When the ball screw is displaced to left of viewer, product transforms into a wheelchair and this transformation is done when the desired entire platform is raised to desired position. Adjustment of the height is done by the help of pneumatic cylinder mechanism. There are four pneumatic cylinders which are placed at the four corners of the seating area which are actuated to adjust the height.

CHAPTER 3 SCOPE OF STUDY AND OBJECTIVE Before starting of any project there is a need to study its objective and also its future scope, it is better to understand it uses and limitations, in this chapter we will look into the scope and objectives of this project and understand its viability. 3.1 SCOPE: Patients in hospitals always wants to overcome the problem of travelling or carrying from wheelchair to stretcher or from stretcher to wheelchair, so to overcome this wheelchair cum stretcher is introduced. It has an added advantage because in hospitals and airports we need to provide both stretcher and wheelchair for their respective uses which makes them costly. But by using this, multi usable one we can reduce the overall cost as it can be used as both wheelchair cum stretcher based on a person’s requirement. For the future, there is always scope for improvement, such as to make it motorized using motors which helps disabled people to drive or operate it themselves. We can also make it renewable using solar energy so that the use of batteries and other electricity equipment is limited and so thus we can make it solar powered convertible wheelchair cum stretcher by use of solar panels which makes it more efficient. 3.2 OBJECTIVES: •

Design a wheelchair with the benefits of both wheelchair and stretcher in single unit.

•

To make Wheelchair cum stretcher accessible to everyone

•

To make the prototype and change it according the requirements of market

•

Theorize on various methods so as to improve design

CHAPTER 4 RESEARCH METHODOLOGY This chapter details everything we read to better understand the designing and construction of the project. These include everything from different aspects of the wheelchair its standards, equipment used and how they work with each other.

4.1 Wheelchair International Standards As with any thing being mass produced, and the fact that this is for disabled people, there has been a lot of research done to find the right measurements for each and every part of a wheelchair. And the image below details the widely accepted results of the research.

Figure 4.1 Wheelchair Standard Dimensions

Though these are the accepted standards, people can have a wheel chair made exactly to match their requirements. The measurements mentioned above are for the mass produced wheel chairs use in hospitals, and public places like railway stations etc.

4.2 Base structure

The base is basically a or it can also be called as a support for the entire assembly. The base is constructed with the help metals such as aluminium, stainless steel, mild steel etc. In the design of this wheelchair, the base consists of a structure that is made up of mild steel.

4.3 Rear wheels The rear wheel is connected to each other using the shaft, such that it will keep it in alignment. This wheel will hold the weight of whole body including the human weight.

Figure 4.2 : Rear wheels with the shaf

4.4 Casters The caster wheels or simply casters are attached to the body of the chair with the help of the bearings. A caster is defined as an wheel that is used to mount at the bottom of any larger object (like "vehicles") which enables that the object can be moved easily. They are available in different sizes, and they are made up of different materials such as rubber, steel, plastic, nylon, aluminium. Here we are providing with two caster wheels in the front for proper balancing and also for changing direction as convenient.

Fig 4.3 : front caster wheel

4.5 Main base structure

This is the main base with the seat on it. Here the base is welded to the shaft of the wheels. The wheels are attached using the nut and bolts, so its removable. The casters are also bolted to the base leg, so as to keep it removable in case we need to change the caster.

4.6 Bearings The direction are to be easily squeezed to fit into the pole in such a case that the bearing is pounded it might create breaks. Bearing is made of steel material and bearing top is mellow steel ball and roller direction are utilized broadly in instruments and machines so as to limit the grating and power misfortune. While the idea of the metal roller goes back in any event to Leonardo da Vinci, their structure and fabricate has gotten strikingly refined. This innovation was purchased to its current situation with flawlessness simply after a significant stretch of research and the improvement. The advantages of such specific research can be gotten when its conceivable to utilize an institutionalized orientation of the correct size sort.

CHAPTER 5 WORK PLANNING 5.1 Planning and Processing The figure given below gives us understanding of the work, timeline on the project.

Figure 5.1

5.2 Brainstorming Structure Design This can be considered as one of the most important phase of the project, in this stage we tried to come up with a suitable design, a feasible and reliable way to properly attach and detach the frame from the manual wheelchair. And also looked ahead the different materials that would be available for the manufacturing such as the wheel dimensions. And also studied various study papers to find the other requirements of the project.

5.3 Manufacturing Strategies and Materials During the second phase of our project, we with the guidance of our mentor discussed varies manufacturing strategies and schemes and the selection of various materials and the equipment’s needed which will fulfil the objective of the project. We choose the materials that will fulfil our requirement and are easily available within our budget. For this project we need a material which is stable and can take the some heavy load without any problem.

5.4 Prototype and Design Approval In this stage we made the design in Solid works and tested its feasibility, for more accurate results we made an exact replica of the wheelchair we procured and took that as the reference, as most wheelchairs are made with standard dimensions, this will work on most wheelchairs. And then checked the feasibility of our design, keeping all the constraints such as dimensions of the wheel, caster Height and others.

5.5 Purchase and Market Survey As it is a student project , so we performed extensive market survey so as to find as the best product as possible these include wheel chair, steel rods, screws etc and also all the tools required for the manufacturing process such as welding machine, cutter etc.

5.6 Testing and Checking Dimensions Before the manufacturing starts, it’s important to verify that the design we have made would be able to perform the desired objectives. For this we rechecked all the dimensions in the design add cross checked with the material we bought so that there won’t be any problem in the next stage.

5.7 Assembly This the final stage where we assembled all the materials, parts which are needed to be welded are performed welding. Remaining all other parts we have made are brought together, attached as per the design Then a test run is done to find any defects and adjustments are made to correct them.

5.8 Tabulated Work Plan Time period

Month

Work Done

20-21

August

Mechanism selection

1-7

September

Designing

8-18

September

Manufacturing Strategies, Cost Analysis

19-28

September

Market survey

1-10

October

Purchasing

11-20

October

Manufacturing

21-31

October

Testing and stability

1-5

November

Checking

for

functional

defects 5-15

November

Compilation of report

15-18

November

Submission of soft copy

21-30

November

Submission of hard copy

Table 5.1

CHAPTER 6 DETAIL DESIGN 6.1 DESIGN The Uniqueness of this design is when the product is in stretcher or bed mode, the height will match the conventional stretcher or bed. The Height is adjustable to bed or stretcher or wheelchair or to any height desired. Conversion from a wheelchair to a bed or a stretcher or vice versa is done by both the patient and handler. Below are the three different platforms of product a. Backrest b. Seating Portion c. Leg support Ratchets are provided at the joint where they meet so that it will lock at each step of conversion assuring the safety while converting. Ratchets are also provided to the Upper legs so that those will be in locked position when the product is in wheelchair mode.

Fig 6.1 DESIGN PART OF STRETCHER

Fig 6.2 Design part of wheel chair

CHAPTER 7

TECHNICAL DETAILS OF THE SETUP MANUFACTURING PROCESS 7.1 PLANT AND MACHINERY REQUIRED Lathe machine:-

Fig 7.1: Lathe Machine A machine is a machine which will rotate the workpiece on its axis to play out a few tasks like cutting, knurling, boring, or distorting, confronting, turning, with devices that are applied to the workpiece to make our necessary object which has the balance or symetry about a axis of rotation. Machines are utilized from numerous points of view, for example, wood turning, metalworking, metal turning, warm splashing, parts recovery, and glass-working. Metalworking machines are utilized to deliver most solids of rotating, plane surfaces and screw strings. Drilling machine:Drilling is characterized as a cutting procedure wherein a drilling apparatus is utilized to cut or broaden a gap of roundabout cross-segment in the strong materials. The drill tool or drill bit device is turning cutting instrument (for the most part we use multi point drill tool). The drill is squeezed upon the work piece and it is pivoted at rate shifts from hundreds to thousands of rpm. This powers the front line against the work piece, cutting off chips or undesirable from the gap to make our necessary one.

Fig 7.2 drilling machine Welding machine : Welding is a procedure that joins materials like metals or thermoplastics, by causing combination or coalescence. This is to be done by dissolving the work pieces and adding a filler material to frame a pool of liquid material that chills off to turn into a solid joint, with pressure some of the time utilized related to warm, or without anyone else, to create the weld. This is not quite the same as fastening and brazing, which include the way toward dissolving a lower-liquefying point material between the work pieces to frame a bond between them, without including the softening the work pieces.

Fig 7.3 : Welding Machine 7.2 MATERIAL USED: (ASTM A36 Mild or Low Carbon Steel) PROPERTIES OF MILD STEEL Introduction: ASTM A36 steel is one of the most ordinarily utilized mild and hot-rolled steel. This kind of steel has great welding properties and it is appropriate for such a large number of procedures, for example, pounding, punching, tapping, penetrating and machining. The Yield quality of

ASTM A36 is less contrasted with the cold rolledC1018, consequently it makes the ASTM A36 to bend more effectively than C1018. Regularly, large diameters across in ASTM A36 are not created since C1018 hot rolled types are utilized for that reason ASTM A36 steel is available/ present in the following forms: •

Rectangular bar

•

Square type bar

•

Circular rods

•

Steel shaped beams such as H-beams, channels and I-beams.

Chemical Composition

Element

Content

Carbon

0.25 to 0.29 %

Copper

0.20 %

Iron

98.0 %

Manganese

1.03 %

Phosphorous

0.040 %

Silicon

0.280 %

Sulfur

0.050 %

Table 7.1

Physical Properties

Physical

Metrics

Imperial

Properties

standard

standard

7.85 g/cm3

Density

0.284 lb/in3

Table 7.2 Mechanical Properties

Mechanical Properties

Metric

Imperial

Ultimate Tensile Strength

400 - 550 MPa

58000 - 79800 psi

Yield Strength

250 MPa

36300 psi

20.0 %

20.0 %

Elongation at Break (in 50 mm)

23.0 %

23.0 %

Modulus of Elasticity

200 GPa

29000 ksi

Bulk Modulus (typical for steel)

140 GPa

20300 ksi

Poisons Ratio

0.260

0.260

Shear Modulus

79.3 GPa

11500 ksi

Elongation at Break (in 200 mm)

Table 7.3

Machining The machinability pace of ASTM A36 kind of steel is around 72%, and normal surface cutting pace of ASTM A36 is 120 ft/min. Machining of ASTM A36 steel is to some degree troublesome and it not as simple as that of machining AISI 1018 kind of steel. Welding ASTM A36 steel is easy to weld utilizing any kind of welding techniques, and the welds and joints so shaped are of amazing quality. Heat Treatment Any carburizing and hardening methods used for the steel type AISI 1018 can be used for ASTM A36 type. ASTM A36 steel is subjected to the following processes: •

Normalizing at 899°C – 954°C (1650°F-1750°F)

•

Annealing at 843°C – 871°C(1550°F-1600°F)

•

Stress relieving at 677°C – 927°C(1250°F-1700°F)

•

Carburizing at 899°C – 927°C (1650°F-1700°F)

•

Hardening at 788°C – 816°C(1450°F-1500°F)

APPLICATIONS ASTM A36 type of steel is having the following applications: It has its use construction of the bridges, buildings such as hospitals and others. It is also used to make steel tanks, bins, steel plates, sprockets, cams, gears, base plates, forgings, ornaments, stakes, brackets, fixtures and jigs etc.

7.3 FACTORS DETERMINING THE CHOICE OF MATERIALS The various factors that determines the choice of materials are discussed below.

1. Properties: The material to be chosen must have the vital properties for our necessary application. The different necessities that are to be fulfilled are weight of the material, surface completion, it's unbending nature, the capacity of the material to withstand against synthetic compounds, administration life, unwavering quality and so forth. The following types of principle properties of materials affect their selection a. Physical b. Mechanical c. From manufacturing point of view d. Chemical

The distinctive physical properties to be concerned are dissolving point, thermal Conductivity, specific heat, coefficient of warm development, electrical Conductivity, magnetic purposes and so forth. The distinctive Mechanical properties to be Concerned are tensile strength, compressive strength, shear strength, bending strength, torsional strength and buckling loads, fatigue resistance, impact resistance, elastic limit, endurance limit, and modulus of elasticity, hardness, wear resistance and sliding properties.

The various properties concerned from the manufacturing point of view are listed below. • Castability, • Weldability, • Brazability, • forgeability, • merchantability, • surface properties, • shrinkage, • Deep drawing etc.

2. Manufacturing Case: The interest for the most reduced conceivable assembling cost is acquired by applying the suitable coating substances that may interest for the utilization of special materials. 3. Quality Required: The quality will influence the assembling procedure and eventually the material. For instance, it is never alluring to do throwing for less number of parts which can be created substantially more monetarily and effectively by doing welding or hand fashioning the steel. 4. Availability of Material: A few materials might be in rare and some might be hard to find. It at that point gets necessary for us to utilize some other material which however may not be an ideal substitute for the material structured. The conveyance of the materials and the conveyance date of item ought to likewise be remembered. 5. Space Consideration: We need to select high strength materials because there are several high forces involved in it and there are also some space limitations to it.

6. Cost: Like other problems, the cost of the material will a major role and it can’t be ignored. So, the factors like utilizing the scrap, look, and non-maintenance of designed part are involved in the selection of proper materials for the project.

MATERIAL USED : S.no

Items

Quantity

Specifications

Material Used

1

Front wheels

2

100mm Dia

Plastic

2

Square Pipe

15

¾ inch

MS

3

Flat Sheet

14 Sqft

16 gauge

MS

4

Rear Wheels

2

622mm Dia.

5

Hinged Pins

4

MS

6

Screw with nut

2

MS

7

Round pipe

2

MS

Table 7.4

SS and Rubber

CHAPTER 8 CONCLUSION This project work has given us a brilliant chance and experience, to utilize our constrained information. We increased a ton of down to earth information and We feel that the task work is a decent answer for connect the doors among institution and industries. The main objective of our project is to make the helper life easy and to make sure the patient is not hurt during the process of treatment. This wheelchair cum stretcher will eliminate the step of shifting or transferring a patient from stretcher to wheelchair or vice versa as it is very difficult to handle the old age people.

CHAPTER 9 REFERENCES 1. V.B. Bhandari, Design of Machine Elements, Tata McGraw-Hill Publication Company Limited, New Delhi. 2. PSG, Design Data Book, section- Materials and Machine Elements. 3. R.S. Khurmi, Strength of Materials, S. Chand & Company Ltd. New Delhi. 4. R.S. Khurmi, Theory of Machines, S. Chand & Company Ltd. New Delhi. 5. Code of practice for power operated elevating work platforms. ,Department of Labour, Wellington New Zealand 1st Edition 1986 6. 10. Ergonomic guide lines for manual material handling. Published 2007 by the California Department of Industrial Relations 7. An

Integrated

Decision

Making

Model

for

Evaluation

of

Concept

Design:http://ctn.cvut.cz/ap/, ActaPolytechnica Vol. 44 No. 3/2004, Czech Technical University Publishing House 8. Bariatric Bed: http://www.camtecproducts.com/3954b.html, Camtec Dr. S. Ray, “Disabled Persons in India", 9. Indian anthropometric dimensions for ergonomic design practice, by NID