Essays on Rotor

Three phase induction motors

Introduction The three-phase induction machine is the most widely used among the rotating machines. An induction machine offers an almost constant speed within its normal operating range when operated off a constant-voltage, constant-frequency, and with the electric power source. The cost of purchasing these machines is very low, and they require little maintenance. However, speed control is difficult and very expensive. Therefore, the rotor current of the three phase induction motors is not induced by electrical connections, but rather the rotation of magnetic field.

Squirrel Cage Rotor construction

The rotor type of the motor is made up of a laminated core which is ...

Executive Project Summary – Malawi Wind Farm

Market Summary Malawi has an electricity production of 2,180 MWh and a consumption of 2,027 MWh. The 95% of the electricity generation comes from hydroelectric sources giving to the high country risks of supply shortages in adverse weather conditions when the water level of the hydroelectric plants is below the technical specifications of the turbines. The country has no other important source of energy having the country the necessity to develop new energy sources different to the hydroelectricity. The surroundings of the Malawi Lake develop winds over the 10 m/s average per year, opening the opportunity to ...

Background

The past several years have been graced with an increase in the production and use of hybrid cars. Numerous automobile companies are exploring and introducing hybrid electric vehicles to the market, with several other companies to follows soon given the demand. It is imperative to outline that the introduction and the fast embrace and use of hybrid electric cars over the past few decades have been stimulated by several factors. Apart from the increasing demand for hybrid cars based on their advantages, the increase in production of these vehicles has been stimulated by the declining fuel reserves and concerns ...

Summary

While all the components of a brake system are important, it is imperative to acknowledge that some components play significant roles in the system as compared to others. One such component is the brake pad. In most cases, the brake pad is referred to as the friction material. It is responsible for generating the friction which opposed the movement of the wheel thus causing a stop to the movement of the automotive. This report is aimed at selecting a section or component of the brake system and presents its modification. As a consequence, the report highlights and discusses the ...

Background Introduction

The paper evaluates the utility of handheld communication devices, about use, flexibility, simplistic and intuitive design, the perceptibility of data, ability to error tolerance, physical effort low in a measure, and approach in use of space and size. The objective of this paper is to give an assessment of the above from research I have conducted. To meet this objective, I have organized it to focus on individual sections for each principal mentioned. I also discuss the designer’s aid to the physically challenged and universal user ability. Later, I finish my paper with the conclusion. The principles of ...

Wave and Wind Power Generation

Wind Physics Basics Wind is atmospheric air which is in motion Energy Source The earth surface absorbs solar radiation differently. Some parts absorb more radiation than other. This creates pressure zones. As a result of pressure, air moves from high-pressure zones to low-pressure zones. This causes atmospheric air motion known as wind. Wind is a renewable source of energy. It is constantly available free of charge (Bhattacharyya, 2011).

Spatial scales

Atmospheric air motion can be categorized depending in terms of spatial scale. Four spatial scales identified include planetary scale, synoptic scale, mesoscale, and microscale. There are various types of spatial scales ...

Abstract

A rotary engine is one of the ancient internal-combustion engines ever used. These type of engines were designed with an odd number of cylinder per row in a radial configuration. The crack shaft remained stationary throughout the operation. One advantage of this kind of engine is that it is a simple engine that utilizes less moving components. On the other hand, a piston engine or a reciprocating engine is a heat engine that uses one or several reciprocating pistons. The piston engine converts pressure into a rotating motion. A piston engine has the capability to seal the gap in ...

Introduction

Energy is a key driver of any nation’s economy. The extent to which it contributes to the performance of all activities surrounding the human life is beyond measure. This is because energy contributes almost fully to the economic development of the economy. In its physical form, energy is classified either as renewable or non-renewable. Renewable energy forms the green energy that can be reused again and is less toxic to the environment. On the other hand, non-renewable energy is exploited once it’s used and mostly pollutes the environment. All this energy forms can be either used directly ...

A brake is a device that produces artificial resistance to the moving part of a machine to stop or slow down its motion. Any machine or its part that is in motion possesses kinetic energy. As per physical laws, energy cannot be destroyed; its form can only be transformed. The brake system converts the kinetic energy of the moving machine or part into thermal, potential or chemical energy. Brake systems are of various types utilized in different applications in industries, home appliances, vehicles, railway trains, and other sectors. This paper has focused on the brake systems used in vehicles, ...

Report of Wind Energy

Rights of nature are things that nature should have. In simple terms, these are some of the things that the human being should do on the earth without the affecting the environment negatively. This kind of ‘rights’ should be implemented to help and the current alarming a rate of devastation. There are several factors that affect the nature of the environment. These include; global warming, the industrial revolution, among others. They are the negative impacts on the environment that violates the rights of nature. Global warming is an occurrence that is caused by the excess carbon dioxide in the ...

Cryptography is an art that is involved in writing and interpreting secret messages. It involves encrypting messages into symbols, numbers, and letters that form a different meaning to conceal the message. In other words, it is the use of codes to conceal a message. In the past, cryptography was very common, especially during epochs of combat where it was deployed to communicate coded messages (Bauer 34). It was an important tool that a particular community would use to conceal messages from their enemies. Today, this mode of communication is rarely used. However, codes are commonly used in technology, especially ...

Abstract

This paper analyzes the importance of generator synchronization to the power grid, the required conditions to perform this procedure and the consequences of imprecise synchronization. For a generator to be synchronized to a grid, the voltage magnitude, frequency, phase sequence and phase angle must match. Manual synchronization depends on an operator to modify generator voltage and frequency, confirm phase sequences of generator and grid, and monitor phase angle difference to timely initiate breaker closure. Automatic synchronizers perform all these function through a computerized system that consists of complex algorithms and control systems, and are categorized in phase lock type ...

Abstract

Permanent magnet synchronous motors (PMSM) are a type of motors that have permanent magnets mounted on the rotors instead of the rotor windings. This particular design gives the motor a few advantages over ordinary induction synchronous motors. The magnets attached to the rotor do not require excitation, which reduces the power consumption in PMSM. This gives the motor high operational efficiency and reduces the motor active diameter. PMSM are therefore associated with applications that require high torque but have limited operation space. The permanent magnets suffer from flux leakage and are therefore aligned in a pattern that minimizes flux ...

Abstract

This article is about two types of engines; the rotary engine and the piston engine. It examines the differences between the two types of engines and their different areas of application. This refers to the specific cars where the two types are used, as well as the market response with reference to the cars in question. Furthermore, the disadvantages and advantages of the two are closely looked into, where it is determined why the piston engine is most preferred by the auto manufacturers and car enthusiasts. Besides, the article concludes with which engine type is suitable depending on the ...

Electric vehicles (EV) are receiving a great interest as an alternative to conventional transportation on oil with the purpose to decrease noise, environmental pollution by reducing carbon emissions and to reduce dependence on oil (Lowry & Larminie, 2012). Moreover, using nuclear and alternative energy including renewable allows to produce zero release of carbon dioxide by vehicles. Currently, road vehicles just reached the stage when electric cars are produced in quantity but still not widely used. First, electric cars have significantly less range. Second, it takes much more time to recharge batteries (several hours for lead acid battery) than to put ...

The dominant sources of noise are usually fans and jets, where the noise reduction can be achieved by various reduction measures. The modelling of the noise sources is necessary to develop, while the tastings are typically provided in wind tunnels and free jets. Generally, fan noise is a function of the rotational tip speed and fan pressure ratio. In this case in order to reduce the fan noise it is better to reduce the rotational tip speed and fan pressure ratio, but consequently, the increase of an engine diameter is to be observed. An optimal value for the rotational ...

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Turbine Engine Lubrication: A Vital Function

Turbine engine has high rotations per minute (RPM) and generates large energy due to compression. The rotating components in the turbine engine (Engine Bearings) must be lubricated at all times for smooth functioning of the engine. The lubricant must flow across the bearings at high pressure (Ehlert, 2011).

Background - Turbine Engines

A turbine is a machine utilizing a rotor or a wheel to produce power that is generating by the motion of the steam, water, air, gas or any fluid. The flow of the gas or the liquid rotates the ...

Introduction:

In a typical hydroelectric power generation system, a dam (water reservoir) is built near water body such as a river to create head (height) that enables water to flow at high pressure via a pipe (penstock) to the turbines that drive the power generators. The fast moving water turns the turbine blades at high velocity, and in turn, the turbine turns the electricity generator’s rotor. The wire coils in the generator’s rotor sweep past the stationary coil (stator) in the generator thus producing electricity. This concept was first demonstrated in 1831 by Michael Faraday, who discovered that ...

A helicopter is a type of aircraft that depends on the work of a rotor, or in some helicopter models, a set of rotors, in order to gain lift and propulsion. In general, helicopters can be classified both as an aircraft and a rotorcraft. Basically, an aircraft pertains to any vehicle that can launched into the sky and actually fly; a rotorcraft, on the other hand, is any vehicle that uses a rotor or a set of rotors to push itself upward, backward, downward, or in lateral directions into the sky. Over the past decades and years, the role ...

An EMS controls the vehicle engine in response to both vehicle and engine inputs. It consists of an electronic control unit composed of a micro-processor with several electromechanical and electronic actuators and sensors. Sensor devices are used to monitor the vehicle engine and detect engine speed, lambda values, crank angle and other engine parameters. The electronic control unit determines the engine ignition time, the quantity of fuel and other engine parameters that keep the vehicle engine running. The ECU does this by use of input values that are calculated based on the inputs that originate from the sensors. Under this ...

INTRODUCTION

The purpose of this report is to furnish the results of a state-of-the-art investigation of wind turbine systems, including a review of the theoretical premises of its operation.

Problem

Increasing energy crisis and global pollution make any investigation on wind energy very important, because wind energy has the possibility to reduce the above two problems. For example, the demand of electricity has increased very much throughout the world because of increased activity in industrial and digital sectors and that is causing very high fossil fuel emission, which has a direct link with global pollution. In this situation, wind energy brings high hopes of ...

Part 1

The advantages of top-down approach to engineering problems A top-down approach is also known as the stepwise design and in most some cases; it is used as a synonym of decomposition. It is essentially the breaking down of a system in order to gain insights into its compositional and elemental sub-systems or sub-groups. In this approach, a brief or detailed overview of the system is formulated and specifying but does not detail any of the first-level sub-systems. Each sub-system is then defined and refined in yet greater detail, and sometimes in many additional sub-system levels, till the entire specification is reduced ...

(Your professor’s name) (Course name & no.) (Date dd/mm/yy)

Avionics, in common parlance, stands for aviation electronics. It is the development and production of electronic instruments for use in aviation and astronautics and such electronic instruments themselves. Avionic systems include control, monitoring, communications and the display and management of multiple systems that are fitted to aircraft to perform individual functions. Such systems majorly include control apparatus performance instruments communication instruments navigation system collision avoidance system black box Avionics are the electronic systems used on aircraft, artificial satellites, and spacecraft. My ...

VESTAS

Contact data. MHI Vestas Offshore Wind A/S Dusager 4 7200 Aarhus Denmark +45 82 44 88 00

Advantages

Wind vitality is an environmentally friendly power supply source and does not bring about contamination. The capability of wind force is colossal; 20 times more than what the whole human populace needs. Disadvantages The assembling and establishment of wind turbines obliges substantial forthright ventures, both in business and private applications. Wind turbines can be a risk to natural life. Cost or value of the turbines. Taking a gander at Vestas, the organization reported a request ...

Introduction

While non-renewable energy sources, notably fossil fuels, comprise the main sources of energy today, concerns over sustainability, high oil prices and climate change, have forced the issue on need for alternative energy sources. The increased contribution of renewable energy sources across all economic sectors means that these technologies can assist countries to meet their respective policy objectives for secure, affordable and reliable energy. Renewable energy technologies remain in their infancy, but are fast gaining ground because of the unsustainably high costs, carbon footprint and pollution caused by fossil fuels. Renewable energy is defined as that which is derived from ...

Solar Power

There are the following ways of generating electricity using solar radiation: use of photovoltaic systems; hot air power - converters of solar energy into the energy of the air flow directed to the turbine generator; solar thermal energy (using the energy generated by the heating of a surface with its subsequent transformation into electrical energy in the steam generators); solar balloon power plants. Electricity produced by the steam generation in the cylinder of the balloon heated by solar radiation. The problem of extraction and processing of solar energy has long worried about the minds of ...

Introduction

Roto Air Inc. is popularly known for its manufacture of Drone helicopters; usually deployed in missions and surveillance purposes. Currently, the Roto air company is faced with major expansion and transition challenges for its new Quick Drop 100 product, which has currently been incorporated into their product portfolio. The company management is preoccupied with relocating this new product to its permanent base in Central Florida, where its official site for manufacturing and sale has been established. However, the project completion is faced with drastic challenges, which are to be delved into in the subsequent section of the paper.

Business Case

As ...

Lab Report 7

Introduction The electrical motor is the device, which converts electrical energy into the mechanical energy. It is must to analyze the characteristics of electric motor. The electric motor is always considered as the dynamic device, which changes its performance influenced by various factors. It is necessary to analyze the important electrical parameters of the electric motor, in order, to use the electrical motor for the particular applications. The electric motor is used in the applications like pumping, home appliances, lifts, cranes, etc. This report discusses about the construction of the electrical motor, and mainly, it discusses about the ...

Introduction

There are many resemblances that can be observed in magnetic and electric phenomena. A magnet comprised of north and south poles which are opposite to each other. The opposite poles attract and likewise repel each other. A magnet has principle property to influence the surrounding space. This surrounding effect of a magnet is known as a magnetic field. Magnetic fields consist of lines of force and force of attraction and repulsion that travel/or move along the lines. The developed forces depend on strength and distance apart the poles. Figure 1: Magnetic lines of force for bar magnet A ...

Let me begin with explaining what Atrial Fibrillation (AF) is. In this condition, the upper chamber of the heart experiences irregular impulses, resulting in rapid and chaotic heart beats. The may case shortness of breath and intolerance to exercise. Its serious long-term consequences include; stroke; serious bleeding; cardiac arrest, and even death. Traditionally treatment used to be started with medications. But, this approach had a limited effect. Since 1990s, hospitals had been performing a procedure, which does not require elaborate surgery or drugs. It focuses on the causes of atrial fibrillation. This procedure is called catheter ablation. In this procedure, a ...

Abstract

A body is said to be moving in a uniform circular motion if it is moving in a circle with a constant speed. The main objective of this experiment was to find the net force that acts on an object of mass m which moves in a circle of radius r at constant speed v and to confirm that the magnitude of that force is given by mv2/r.An experiment was done using centripetal force apparatus by hanging masses on it and computing the force required to stretch the string, the masses were then subjected to a rotational frequency and the average frequency determined. The ...

Introduction

A wind turbine is a device that uses the kinetic energy derived from wind to create mechanical energy. This simply means the wind’s force pushes the blade into motion. Different wind turbines have different ways of extracting wind energy like most machines. Aerodynamics, on the other hand, simply refers to the flow of air about a body. This makes aerodynamics to be a critical aspect of wind turbines as this flow of air about the turbines is what determines its power output. This paper focuses on the aerodynamic behavior of wind turbines (Hansen 21). Calculation of forces acting on a body ...

The wind is a clean and plentiful source of renewable energy that is currently being explored worldwide. It offers a reliable alternative not only for non-renewable sources of energy but also renewable energy including solar energy (Thomas 119). Wind energy is used for various purposes including sailing vessels, powering factory machinery, pumping water as well as grinding grain. Turbines are used to generate wind energy in a process called Wind power. Wind power is widely recognized for its ability to generate power that can be utilized feasibly and economically in large quantities. It is an environmentally friendly process since it produces low ...

Hybrid Wind and Solar Powered Outdoor Lighting

Team: MET-421-001 Senior Design Project I Winter 2014

Abstract 1

Project Description 2 Photovoltaic Cells 3 Wind Turbine 4 Integrated Controls Unit 6 Battery 7 LED Lighting 8 Patent /Market Review 9 Economic Analysis 9 Conclusion 13

References 14

Appendix 15 Abstract The United States Department of Energy has laid out a vision in 2011, which includes to have the U.S. secure a leading role in clean energy technologies. With current global considerations to conserve natural energy resources and convert to more sustainable methods of power generation, applied efforts need to be ...

International Transport Management

International Transport Management

Marine news is a magazine that gives information on the North American inland, offshore and coastal maritime community. It focuses on giving people information they should know about the industry. The information spans a variety of related fields that entail different expertise and appeal to a variety of interests. One of their top stories were on the right to a bon voyage. According to Haun (2014) who is a reporter for the magazine, this has been one of the issues in the priority list for National Transportation Safety Board. It came about after an accident by the commuter ferry Seastreak in ...

Authors’ Name:

The portability of the wind energy has been until recently, a major knock. However, the energy niche is quickly growing with development as small portable wind turbine generators (Kleinschmidt, 2008). The gadget is a wind power harnessing device that is small enough or can be taken down, packed up and moved with easily. The generator is powerful enough to provide energy for charging smartphones and other USB devices (Kleinschmidt, 2008). The operation principle for portable wind turbine generator is less the same that of large wind turbine generator. The device comprises of a drive train that has the main shaft, a hub, ...

Introduction 3

Background 3 Research questions 4 Research objectives 4 Rationale for the research 5 Plan for work 6 Literature review 7 Wind power evaluation 9 Tourism impact of wind energy on Arroyo 10 Costs 11 Benefits 12 Methodology 12 Data collection 13 Primary sources 13 Secondary sources 14 Data analysis 14 Reliability and validity 14 Ethical considerations 15 Conclusion 15

References 16

Introduction Background The prospect of increasing energy prices in Puerto Rico has become an aspect of concern in the societal framework. ...

1. Introduction The motor is an electrical device, which converts electrical energy into the mechanical energy. The electric motor operates by the interaction of the magnetic and the current to generate the force. The electric motor operates in generating or braking modes. The industrial fans, pumps, and motors are being powered by the direct electric current sources. The small types of motor is being found in the electric watches [1]. The motor has highly standardized dimensions with the good mechanical power to the industries. The high capacity motors is being found in the ship propulsion and compression. The ...

Objective

1. Introduction An induction motor is an AC motor, which the electric current in the rotor produces the torque. An induction motor requires commutation. All parts of the energy is transferred from stator to rotor. Three phase squirrel cage induction motor is widely used in the industrial application. In induction motor, the AC power creates the rotating magnetic field that rotates the rotor. This rotating magnetic field produces the opposing current in the rotor. This creates the magnetic field in the rotor, which opposes the rotating magnetic field. The rotor will start to rotate in the direction of ...

Candidate’s Name

Abstract The paper explores the technology of hydroelectric power generation. It throws light on how the technology works, brief historical viewpoint, its benefits and shortcomings, the transmission aspect of the technology, its future potential. Hydroelectricity is the largest source of renewable energy throughout the planet. We will learn how it provides a double benefit of energy and water management provisions leading to accelerated growth and development. Though initial costs related to a hydroelectric project are high, they provide a long term source of energy with considerably low running and maintenance costs. This paper also highlights how water resources have been utilized ...

ENGINEERING

Abstract Wind turbines have become a practical and efficient fossil fuels replacement for the generation of electrical energy. Characteristics optimized include weight, ease of manufacture and structural integrity. Ease of manufacturing has a direct relationship to costs. Lighter materials for blade construction are necessary to decrease blade weight and lengthen blades. Carbon fibers or composites of glass and carbon fibers are lighter than glass fibers. Hypothesis: controlling the speed of the infusion will allow the capacity to manage the speed of the infusion process and in that way control of the final composite material. Results showed that 68.5 meters has ...

Abstract

The purpose of this paper is to provide a basic overview of lean supply chain methodology. This will also provide how the concept was evolved over the years. The paper will provide a brief overview of the basic pillars of lean supply chain and then look at the tools used to implement and monitor lean supply chain methodology. This paper also will discuss the limitations of the current lean supply chains methodology. It will then compare lean supply chain concepts with agile supply chains and green supply chains to bring out the similarities and differences. Finally the paper will provide some ...

Lab Report: Renewable Energy Lighting System Design

Introduction Communities around the country as well as around the world are setting sustainable development goals. Twidell and Weir (2006, 2) define sustainable development in general terms as “living, producing and consuming in a manner that meets the needs of the present without compromising the ability of future generations to meet their needs.” Renewable energy sources are critical for sustainability. Renewable sources like wind and sun are different from fossil fuels because intense human labor is not necessary. Renewable resources do not negatively impact the environment which is also an important factor for reaching sustainability goals. Twiddel and Weir ( ...

Introduction

Most of the renewable energy experts in the world pay more attention to wind energy. Wind energy which is referred to as kinetic energy is converted to electricity power which can be used to power homes and businesses. ( Morthorst, G & Poul, E. 2002). One of the equipments which can be used to convert kinetic energy from wind to electricity is wind turbine. It can be made in various designs which include horizontal and vertical axis wind turbines. The most common design is the horizontal wind turbine. A wind turbine can be referred to by several names depending on ...

The dream of flying was born more than two thousand years before anyone ever made attempts realizing that dream. The kite was the first invention by human beings to know the skies. The first ever record of kite flying was in China where a Chinese general flew a distance of around two hundred meters in order to survey their enemy's territory. The ideas in flight went on advancing and from the kite the hang gliders arose. It is crucial for one to note that the Wright brothers were responsible for the first ever air borne structure that could carry the weight ...

Table of Contents 1.0 Introduction 3 2.0 Basic Components of a Jet Engine 3 2.2 Compressor 3 2.3 Combustor 4 2.4 Turbine 4 2.5 Exhaust Nozzle 4 3.0 Classification of Jet Engines 4 3.1 Turbojet engines 5 3.2 Turboprop Engines 6 3.3 Turbofan Engines 6 3.4 Turboshaft Engines 7 4.0 Creation of Thrust in a Jet Engine 7 5.0 Conclusion 9 6.0 References 10

1.0 Introduction According to Hunecke (1997), jet engines ...

There is no doubt that the negative effects of non-renewable energy have increased the need to adopt policies that encourage wider utilization of renewable sources of energy. This can be in part due to the necessity of minimizing dramatic costs associated with advancement in technology and as well, in part due to the need to reduce carbon dioxide emissions (Gasch, and Twele 20). Similarly, the increasing global energy demands have also increased the attention given to non-renewable sources of energy. Among other sources, wind energy is among the leading sources of renewable energy. Being a clean natural resource, wind offers ...

Basic Modules of Gas Turbine High Bypass Engine

Air Inlet Section: As shown in figure 5, the air inlet section is the most forward section of the engine. This section forms the air inlet for the engine and houses the inlet guide vanes. The purpose of the vanes is to direct the incoming air at the proper angle to the first fan stage. The vane at the bottom of the air inlet is thicker than the others in order to accommodate engine tubing. As indicated in figure 6, the no. 1 bearing support assembly is mounted in the center of the compressor inlet case. Behind the front ...

The dream of achieving a vertical flight has always been with Igor Sikorsky, a Russian-born aeronautical engineer for years before managing to develop the first machine that was associated with all we called helicopter today. He actually made several attempts until the dream was achieved. Some of his important failures regarding the building of helicopter is that of Circa that was built in 1910. The dream of eventually being carried into the air vertically came true eight years after submitting a patent for a modern looking helicopter in 1931. The first practical helicopter was the VS-300 that lifted him up. He never ...

Wind Energy: Advantages, Disadvantages and Solutions

Harnessing the power of the wind is nothing new. For centuries, it has powered sailing ships, provided energy for windmills and pumped water. Nowadays, with the help of turbines, wind provides us with electricity.

Introduction

I am proud to be a member of the LM Wind Power Group in their blade manufacturing division. Within 30 years of operations, LM Wind Power has produced around 150,000 blades. As such, wind energy is an important subject for me. As an energy source that is renewable and more environmentally friendly than traditional electricity generating technologies, I consider wind energy to be a viable alternative ...

Introduction

Wind energy has been in use as far back as 3000 B.C., when sailors in Egypt utilized this energy to move their boats. Today, wind energy is hailed as an important source of energy and is tapped in various regions around the world. Its importance stems from two factors: (1) it is renewable and (2) it is a clean source of energy that does not generate environmentally harmful emissions. To harness wind energy, a wind turbine is used. A turbine converts the kinetic energy of the wind into rotary mechanical energy, which can then be converted to electrical energy (“Wind turbine,” ...

1. Abstract

The proposal aims at to giving a solution to the problem of low power output by designing a power generation system that maximizes power output by mounting the turbine on a D.C generator with a suitable coupling. This generator is then connected to the water pipe. The turbine is designed to generate electricity by converting kinetic energy from water flows to electric energy. The use of this technology proves sustainable as it works under minimum maintenance. In this proposal is included the conceptual approach, results ad conclusions arrived at validating the significance of conducting this research. In include but not limited to the ...

Introduction

The beginning of the concept of aviation began in Chinese in the fourth century A.D. In 400 B.C a toy that consisted of feathers at the end of a stick was spun between the hands to generate a lift and after its release it provided a free flight, It is assumed that those who build the toys were inspired by the auto rotating nature of seeds from trees such as Sycamore. 1

In the year 1480, Leonard da Vinci discovered that a screw shaped device well made from a starched linen can rise in air if turned quickly.

Biography of Leonard da Vinci

He was born on April ...