SWING POWER GENERATION

ABSTRACT

Electricity need of today’s modern world is growing day by day because of the continued increase in consumption due to the growing population. Many concepts are being carried out to generate electricity on a local basis and utilize the same for said to locality. This paper is about a swing, which is used by children for playing that produces electricity while being used.

In its simple construction, the swinging action of swing makes the horizontal beam member turn through some angle. This horizontal shaft is connected to a wheel which turns along with it. Now this motion is transferred onto another ring of small diameter which rotates proportional to the angle of swing of the big wheel, in this was angular movement is converted to complete rotations. This is done by using a flexible leather belt connecting both the wheels externally. The smaller ring is connected to a step-up transforming which in this case is used as a motor to generate electricity. This is done by rotation of the ring cutting flux lines inside the motor. This electricity generation takes place in both to and fro motion of the swing which makes the electricity generated in AC form. This is converted to DC current and amplified by using a special circuit of a bridge rectifier.

The electricity thus produced is free of cost and is ecologically friendlier and can be used for local use by storing it in a battery during the time of operation. This way of generation of electricity if implemented at various parks, playhouses, schools etc. can certainly lower down the load on the main grid thus helping saving electricity.

CHAPTER 1

INTRODUCTION

1.1 SWING POWER GENERATION

Energy is the driving force of modern societies, and the generation and utilization of energy are essential for socio-economic development. Per-capital energy consumption levels are often considered a good measure of economic development. In recent years, energy scarcity has become a serious problem due to depletion of non-renewable energy sources, increasing population, globalization of energy-intensive economic development, environmental pollution, and global warming.

In recent years, there have been many interesting developments in the field of human power conversion. In the present project, a method of harnessing the power of children's play in playgrounds and public places, on a device such as a swing is proposed.

When a large number of children plays in a school playground, part of the power of their play can usefully be harnessed resulting in significant energy storage. This stored energy can then be converted to electricity for powering basic, low power appliances in the school such as lights, fans, communications equipment, and so on. The method provides a low-cost, low-resource means of generation of auxiliary electric power, especially for use in developing countries.

In the proposed method, a simple belt and wheel mechanism is used along with a motor to generation and storage of electricity. Use of this method is very economical and simple in construction. The lower efficiency of the resulting system is compensated by the simplicity, safety, low cost of operation and low maintenance cost.

The swing can be used in any atmospheric conditions, no heavy equipment is used and no harmful effects for the child using it. The electricity can be stored in batteries, and used to power dc-operated lights and appliances.

In this paper, we have proposed a methodology in which we generate electricity during both forward and backward motion of the swing, without adding any resistance to the person swinging. This is done by using a wheel and belt mechanism and converting the AC output generated to DC using a suitable mechanism makes the construction simple.

1.2 OBJECTIVE

The objective of the paper is to provide a method to convert obtained mechanical energy during the movement of seating of swing set into electrical energy along with no added effort and also storing the electricity thus generated into a battery, which can be utilized whenever needed.

CHAPTER 2

METHODOLOGY

The main aim of this project is to utilize the mechanical energy generated during the swinging action of the swing set and convert it into electricity and store the electricity thus generated into a battery. It works based on the principle that energy can neither be created nor destroyed but can be converted from one form to another.

2.1 DESIGN OF THE MODEL

                                                                                     Figure 2.1 Model Design

2.2 HAND BAR AND SEAT

The hand bar connects the shaft and the seat of the swing through the pad. The main objective of the hand bar is to provide stability to the motion of the swing and also help carry the load on the seat.
The Wooden seat is attached to the MS holding bar rigidly using fasteners. Here we are using Plywood as material for the seat. The seat is attached to the shaft by means of hand bar through a pad.
A material used: Mild Steel (Hand bar) & Plywood (Wooden Plate)

2.3 SHAFT

A shaft is a rotating element, which is used to transmit power from one place to another. The power is delivered to the shaft by some tangential force and the resultant torque or tension moment set up within the shaft permits the power to be transferred to various machines linked up to the shaft, in order to transfer the power from one shaft to another the various members such as pulleys, gears etc, are installed on it. A material used is C45 Steel.
This member causes the shaft to bend. In other words, we may say that a shaft is used for the transmission of torque and bending. The various members are mounted on the shaft by means of keys.
Shafts are to be designed on the basis of rigidity considering the following two types of rigidity.

1. Lateral rigidity

2. Torsional rigidity

2.3.1 Lateral Rigidity

It is important in case of transmission, shortening and running at high speed where small lateral rigidity is also important for maintaining proper bearing and clearances a for correct gear teeth alignment if the shaft is of uniform cross-section then the lateral deflection of a shaft may be obtained by using the deflection formulate as in strength of materials.

2.3.2. Torsional Rigidity

The torsional rigidity is important in the case of transmission shafts deflection 2.5° to 3°/m. The length may be used as limiting value, the widely used deflection for the shaft is limited to 1 degree in length equal to 20 times the diameter of the shaft.

2.4 BEARING

A standard pedestal bearing housing for 20 mm axle size is used. Such two number of pedestal bearings are used in this project which is clamped on the angles at the top portion.

Specifications:

• Material - Cast iron

• Inside Diameter - 20mm

• Centre Height - 33.3mm

• Overall Height - 65mm

• Length - 127mm

• Depth - 32mm

The figure shows the required dimensions of the bearing used,

Figure 2.2 Part drawing of Bearing

2.5 PAD

Pad is used for attaching the seat and hand bar to the shaft. The material used: C45 Steel By using a pad the hand bar can be fixed rigidly to the shaft. Above fig. shows the brief design that we are going to use. It is made of MS, machined and drilled to proper dimensions.
This is used to attach the holding bar to the shaft. Facing, Turning and Drilling operations are performed to get the required dimension.
The figure shows the required dimensions of the Pad used

Figure 2.3 Fabricated pad

2.6 BELT AND WHEEL

A wheel that is used is a normally used cycle wheel which has a groove on the outer surface for meshing with the belt used. The wheel rim used is of the 13-inch radius.
The material used for the wheel – Aluminium Material used for the Belt - Leather
The angle of contact between both the pulleys and the belt is as shown below:
Diameter of the larger pulley (D) = 0.325m

2.7 STEP UP MOTOR AND BATTERY

A step up motor is connected to a rectifier circuit and an amplifier circuit which is then connected to a lead acid battery to store the energy developed.

2.8 L - ANGLE

L – Angles of required dimensions are cut as per the requirements. Later holes are drilled at required positions based on a design for introducing fasteners during the assembly.

2.9 ASSEMBLY

Following are the main steps involved in the assembly operation,

• Building the frame

• Attaching the Shaft and Holding bars to the top of the frame.

• Attaching the wheel and belt pulley mechanism and Generator to a side of the frame to form the working mechanism

The final assembly of the model looks as follow

Figure 2.4: Side view of the assembled model

                     

Figure 2.5: Front view of the assembled model

CHAPTER 3

WORKING PRINCIPLE

During the forward stroke & backward stroke of swing, some torque is induced in the shaft. The shaft is mounted between two bearings. At one end of the shaft, a large sprocket is attached rigidly, this sprocket pivots over shaft axis when the shaft is displaced. The larger sprocket is attached to a smaller sprocket using chain. The smaller sprocket is mounted on a sprocket shaft, on one side of which a flywheel is attached and on another side a generator is mounted with help of screws

When the seating of the swing set moves forward & backward some torque is induced in the shaft by the holding bars of a swing set. This torque displaces the larger sprocket which is pivoted over an axis of shaft causing the angular displacement. This angular movement is converted to rotational motion of smaller sprocket by chain attachment. The sprocket rotates the flywheel which runs the generator, thus producing the electricity. The flywheel is used to smooth the flow of energy as the power is produced in alternate stroke. The electricity thus produced is stored in a battery by using electric circuits as shown in figure 3.1

               

Figure 3.1 Working Mechanism

3.1 ADVANTAGES, LIMITATIONS & APPLICATIONS

Following are the Advantages, Limitations & Applications of developed model,

Advantages :

• Pollution free electricity generation.
• This power can be stored in a battery array so as to use it further.
• Can be installed at places such as schools, playgrounds where mass transit of children is sighted e.g. hotels, fairs etc.
• Easy installation and maintenance.
•  Simple mechanism.

Limitations

• Require periodic checkups.
• Power generation is not continuous.
• Implementation cost is a bit higher than overall average production cost

Applications

The system can be employed in places such as,

• Gardens
• Playgrounds.
• Schools 
• Nurseries 
• Parks

CHAPTER 4

CONCLUSIONS

• The proposed system offers an innovative method to generate electricity from the mechanical energy produced during the swinging action of the swing seat with no added effort to the person sitting on it, which would otherwise be wasted.
•  It is an attractive technology for optimal use of available sources.
• The proposed system can be used to generate electricity effectively in a non–polluting manner at various places like schools, parks, playgrounds, garden, etc. 

REFERENCES

[1] 

R.S.Khurmi and J.K.Gupta “Machine Design” Eurasia Publications, Revised edition 2005.

[2]

J.B.K Das and P.L Srinivas Murthy “Design of machine element I & II” Sapna publications 6th revised edition 2011.

[3]

Lingaiah “Design data handbook” Volume-1 and Volume – 2

[4]

“Swing Electricity Generation System”, available www.beprojectreport.com/mechanical-abstract/c1-swing-electricity-generation-system.html

[5]

“Stepper Motor Voltage Doubler Circuit”, available at http://www.reuk.co.uk/Stepper-Motor-Voltage-Doubler-Circuit.htm

[6]

www.Wikipedia.Com

[7]

Leao Rodrigues ‘’Wave power conversion systems for electrical energy production’’