DESIGN AND FABRICATION BLUETOOTH OPERATED STEP CLIMBING WHEELCHAIR

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1 DESIGN AND FABRICATION BLUETOOTH OPERATED STEP CLIMBING WHEELCHAIR 1 Jithin M.R., 2 Rino P.J, 3 Alwin Thomas, 4 John Rison, 5 Alex Kurian 6 Deepak K 1-5 Students of Nirmala college of Engineering, Meloor, Chalakkudy, India. 6 Asst.proffessor,Mechanical department of Nirmala college of Engineering,Meloor,Chalakkudy, India. Abstract: The movement of elderly and physically challenged people from one place to another is made possible by a device known as wheelchair. The aspect of dealing with stairs continues largely unresolved in case of the mobility of these kind of people. To overcome this, focusing the possible improvements in wheelchair we are doing this project. Here our project precisely aims at the development of an automatic step climbing wheelchair controlled by using Bluetooth. Our aim of creating this automatic step climbing wheelchair is to help the disabled and the elderly people to overcome one of the most architectural barrier, stair. The mechanism of wheelchair that we are developing here is tracked mechanism using conveyor belts and rollers. A Bluetooth control is used to control the movement of the step climbing wheelchair. 1. INTRODUCTION Man Mobility is the most common problem not only for elder but also for disabled people, a problem which devices like wheelchairs have done so much to alleviate. Wheelchairs and power wheelchairs as a means of transportation play an important role in the life of elder and disabled people because those devices assist them in becoming more mobile and independent. Their mobility is not equivalent to the normal people, Wheel type is commonly used due to its adaptability to different surfaces and can be further enhanced as a power wheelchair, but most of those systems requires the help of an experienced person to ensure stability while climbing or descending stairs. Stair climbing is one of the most attractive performances of mobile robot. In this project, we have considered the redesign of the manual wheelchair. We have gone through the by means of literature survey and the importance of the existing product. A Bluetooth circuit is connected to the system for wireless communication between mobile and step climbing wheel chair. Bluetooth system will be more technologically advanced when it compares to the present wheelchairs. The most important thing is that, the mental stress faced by the handicapped persons will be more in controlling the system. It will be very easy to control forward and backward using mobile phones. So it will reduce the manual work done by the user or helper. 2. COMPONENTS FRAME BATTERY DC MOTOR SPUR GEAR BEARING WITH CAP SHAFT CONVEYOR BELT ROLLER BLUETOOTH CIRCUIT 4. CONSTRUCTION The Structure of the wheel chair consist of three shafts and six rollers. The conveyor belt is rolled over the three rollers in the shape of a triangle.the rubber strips are connected to the rubber strips are attached to the belt for providing. Two batteries which are connected in series on the structure delivers charge to the motor which is also connected on the structure for working of the step climbing wheelchair.this motor is used to deliver power to the stair climbing conveyor belt setup of the structure.the dc motor is coupled to the spur gear with the help of suitable arrangement. The gear is used to reduce the speed of

2 the vehicle so that the torque increases. The output of the gear power is transferred to the shaft and this shaft is connected to the rollers. The conveyor belt is rolled over the rollers,with the help of these rollers and belts the wheel frame will start climbing the steps. The Bluetooth receiver circuit is fixed to the wheelchair. Mobile phone is used to control the wheelchair.it can be moved forward and backward using the play store app. 4. 3D MODEL Power, P = 90 w Speed of pinion, n =60 rpm No. of teeth on pinion, Z1 = 24 No. of teeth on gear Z2 = 42 Gear ratio, i=z2/z1=1.75 Pressure angle, α = 20 degree Material for pinion and gear as cast iron Pinion is weaker Lewis form factor y = /z for 20 degree y = /24 = Module m = 1.26 [Mt]/σbyΨmZ Design twisting moment, [Mt] = Mt k dk for symmetric scheme kdk = 1.3 Normal twisting moment transmitted by the pinion Mt =97420 KW/ n = /60 = Kg fcm [Mt] = = 190 Kgf cm Design bending stress, σ b =(0.717 BHN+115)N/mm² Surface hardness,hb=240 BHN σb=(( )+115)= N/mm²= kgf/cm² In general, m=10 3 m 1.26 ( ) =0.168cm=1.68mm standard module, m=2mm diameter of pinion, d1=mz1=224=48mm diameter of gear,d2=mz2=2 42=84mm face width, b=3pc =3 π m=3 π 2=18.85mm Figure 1 3D Model created using Autodesk fusion DESIGN AND CALCULATION P.M.D.C MOTOR:- Diameter of roller = 10 cm Required speed N = 60 rpm Normal reaction = 400 N Coefficient of friction COF = 0.7 Force F = = 280 N Torque T = F radius = =14 Nm Power, P = (2πNT)/60 = (2πNT)/60 =87.96 watts SPUR GEAR SHAFT Power, P =90 w Speed, N = 60 rpm Gear ratio, i=1.75 N =60/1.75 =34.28 rpm Power, P = (2πNT)/60 Torque, T= (90 60)/ (2π 34.28) =25.07 Nm We know that, T= (π/16) d 3 Taking shear stress =55 N/mm 2 = N/m 2 d = mm = 15 mm BEARING Radial load, Fr = 400 N Axial load, Fa= 280 N Diameter of shaft, d=15 mm N = 60 rpm

3 Life in hrs = hrs Select deep groove ball bearing select series life in mr,t=(life in hrs 60 rpm)/10 6 =( )/10 6 =72mr L10=1 mr K=3 for ball bearing Equivalent load, p=(x fr+yfa)s Service factor,s=1.5(rotary m/c with no impact) Fa/Fr=280/400=0.7 e=0.24 Fa/Fr>e X=0.56 Y=1.8 P=(( )+( )) 1.5 P=1092N Therefore c=(72/1)^(1/3) 1092=4542.9N C=454.3Kgf For d=15mm Select 15Bcb2SKF6202 deep ball groove bearing Dynamic c=610kgf No. of teeth on pinion=z1=24 No. of teeth on gear,z2=42 Diameter of pinion,d1 =48 mm Diameter of gear,d2=82mm Module, m=2mm Material is cast iron SHAFT Diameter = 15mm Material mild steel 3 no.s BALL BEARING Deep grove ball bearing SKF 6202 Diameter,d =15 mm Bearing cap, diameter D=45 mm Thickness, B=11 mm r=1mm Corner radii on shaft & hearing, r1 =0.6 Static Co=335 kgf Dynamic C=610 kgf Maximum permissible speed =16000 rpm BELT Length of the belt=2c+ π 2 (D+d)+(D_d)² 4C Centre distance between two rollers=50 cm Diameter of rollers, D=d=9 cm L=(2850)+ π (9+9)= cm 2 Length of the belt in one side between two rollers=128.27/2 =64.14 cm Total length of the belt are arranged in 3 rollers= =192.4 cm Width of the belt=20 cm Width of the roller=20+2.5=22.5 cm 6.SPECIFICATIONS OF COMPONENTS BATTERY Lead acid battery 12v,7amp 2 numbers DC MOTOR Power=90w Output speed =60rpm Voltage=12volt Permanent magnet type SPUR GEAR BELT Total length of belt,l=192.4 cm No. of belt= 2 Belt width,b =20 cm Roller width = 22.5 cm WHEEL CHAIR FRAME Bottom frame, Length, l=60 cm Breadth, b=45cm Wheel chair height, l=100cm b=37.5 cm Material M S ROLLER Length, l=22.5 cm Body thickness, t=1.5 cm Material M S 6 Nos Diameter of roller = 9 cm Diameter of round plate, d=10 cm Thickness =6 mm RUBBER STRIPS Length,l= 19 cm Breadth, b =2.5 cm

7. FABRICATION AND ASSEMBLY Figure 2 Assembly of shaft, gear and roller 6. BLUETOOTH CIRCUIT This device will helps us for wireless communication between mobile and step climbing wheel chair.

The AT89C52 is a low-power, high-performance CMOS 8-bit microcomputer with 8K bytes of Flash programmable and erasable read only memory (PEROM).

The on-chip Flash allows the program memory to be reprogrammed in-system or by a conventional nonvolatile memory programmer.

4 7. FABRICATION AND ASSEMBLY Figure 2 Assembly of shaft, gear and roller 6. BLUETOOTH CIRCUIT This device will helps us for wireless communication between mobile and step climbing wheel chair. The Bluetooth circuit mainly consists of Microcontroller, Bluetooth module, relays and display unit. The micro controller used is AT89C52. The AT89C52 is a low-power, high-performance CMOS 8-bit microcomputer with 8K bytes of Flash programmable and erasable read only memory (PEROM). The device is manufactured using Atmel s high density nonvolatile memory technology and is compatible with the industry standard 80C51 and 80C52 instruction set and pin out. The on-chip Flash allows the program memory to be reprogrammed in-system or by a conventional nonvolatile memory programmer. By combining a versatile 8-bit CPU with Flash on a monolithic chip, the Atmel AT89C52 is a powerful microcomputer which provides a highly flexible and cost effective solution to many embedded control applications. The fabrication of the wheel chair frame is done through various operations like welding, sawing, metal cutting, drilling etc. The three shafts re connected to the system having rollers and gears. The third shaft is welded so as to tighten the conveyor belt. The rubber strips are attached to the system for providing grip with bolts & nuts. Figure 4 Bluetooth circuit Figure 3 Assembly of conveyor belt

7. CONCLUSION ISSN No: 2309-4893 In this project, we developed a step climbing method with a tracked mechanism. Our project working with satisfactory conditions and at low cost.

5 7. CONCLUSION ISSN No: In this project, we developed a step climbing method with a tracked mechanism. Our project working with satisfactory conditions and at low cost. We are extremely happy to complete the project in a short period and had a good working experience. By using the wheelchair handicapped and elderly person can climb stairs without the help of an external agents or persons, by just controlling this stair climbing wheelchair using a mobile Bluetooth. Figure 5 Step climbing wheelchair climbing wheelchair 4. Hongbo Wang, Li He and Qi Li, When zang, Dong zang and Peng Xu 5. Novel Design of a Wheelchair with Stair Climbing Capabilities 6. Basilio Dobras Castillo, Yen-Fu Kuo and Jui-Jen Chou 7. A Novel Stair-Climbing Wheelchair with Transformable Wheeled Four-Bar Linkages 8. Yusuke Sugahara, Naoaki Yonezawa and Kazuhiro Kosuge 9. Modeling of a Stair-Climbing Wheelchair Mechanism With High Single-Step Capability Murray J. Lawn, Member, IEEE, and Takakazu Ishimatsu 10. Wheelchair.q, a mechanical concept for a stair climbing wheelchair Giuseppe Quaglia, Walter Franco and Riccardo Oderio 11. PSG College of Technology, DesignData,kalaikathir Achchangam Publications 12.. R.S Khurmi,J.K Gupta, Machine Design, Eurasia publishing House 13. Kenneth J. Ayyala: The 8051 Microcontroller Architecture, programming & Applications. Second Edition., Penram International., Gaonkar: Micro-processor Architecture Programming and Application, Wiley Eastern Ltd., ACKNOWLEDGEMENT We would like to thanks our guide Mr. Deepak Assistant professor of Nirmala college of engineering, Chalakkudy and Mr. Kannan HOD of Nirmala college of engineering, Chalakkudy for their valuable support for developing this project. 9. REFERENCES 1. A Novel Step Climbing Strategy for a Wheelchair with Active-caster Add-on Mechanism. 2. Yu Munakata and Masayoshi Wada, Member, IEEE 3. Research on kind of Leg- wheel stair

DESIGN & IMPLEMENTATION OF AUTOMATIC STAIRCASE CLIMBING PLATFORM

DESIGN & IMPLEMENTATION OF AUTOMATIC STAIRCASE CLIMBING PLATFORM Sayali H. Kakade 1, Ankit I. Kohare 2, Somen P. Rakhunde 3, Kiran N. Borkar 4, Poonam G. Bhoyar 5, Jayant Y. Hande 6 1 Student, Electronics