Introduction: in this project we divided project in two parts- Electromagnetic brakes and regenerative brakes. In regenrative brakes we will genrate electricity when brakes applied. We will use 12 volt dynamo which will charge battery. We can use light for brake bulbs also or can charge electricity in battery.
In this project our motive is to make project on electromagnetic system. We studied lots of projects. But we want to make some different project. Then finally we decided to make electromagnetic breaks. Firt of all we will move a vehicle system. Then we will attach a electromagnetic solenoid system. This solenoid system will be work with battery. We will use IR proximity sensor to sense object in front of vehicle. We cant use long distance sensor for this purpose. We can also use ultrasonic sound waves system also. But this system will not work in frequency areas or jammer areas. Project will need a 12 volt two wheeler vehicle battery to control breaks.
What is Electromagnet.. An electromagnet is a type of magnet in which the magnetic field is produced by the flow of electric current. The magnetic field disappears when the current is turned off. Electromagnets are widely used as components of other electrical devices, such as motors,generators, relays, loudspeakers, hard disks, MRI machines, scientific instruments, and magnetic separation equipment, as well as being employed as industrial lifting electromagnets for picking up and moving heavy iron objects like scrap iron.
A simple electromagnet consisting of a coil of insulated wire wrapped around an iron core. The strength of magnetic field generated is proportional to the amount of current.
Current (I) through a wire produces a magnetic field (B). The field is oriented according to the right-hand grip rule. An electric current flowing in a wire creates a magnetic field around the wire (see drawing below). To concentrate the magnetic field, in an electromagnet the wire is wound into a coilwith many turns of wire lying side by side. The magnetic field of all the turns of wire passes through the center of the coil, creating a strong magnetic field there. A coil forming the shape of a straight tube (a helix) is called a solenoid. Much stronger magnetic fields can be produced if a “core” of ferromagnetic material, such as soft iron, is placed inside the coil. The ferromagnetic core increases the magnetic field to thousands of times the strength of the field of the coil alone, due to the high magnetic permeability μ of the ferromagnetic material. This is called a ferromagnetic-core or iron-core electromagnet.
Magnetic field produced by a solenoid(coil of wire). This drawing shows a cross section through the center of the coil. The crosses are wires in which current is moving into the page; the dots are wires in which current is moving up out of the page. The direction of the magnetic field through a coil of wire can be found from a form of the right-hand rule. If the fingers of the right hand are curled around the coil in the direction of current flow (conventional current, flow of positive charge) through the windings, the thumb points in the direction of the field inside the coil. The side of the magnet that the field lines emerge from is defined to be the north pole. The main advantage of an electromagnet over a permanent magnet is that the magnetic field can be rapidly manipulated over a wide range by controlling the amount of electric current. However, a continuous supply of electrical energy is required to maintain the field. The material of the core of the magnet (usually iron) is composed of small regions called magnetic domains that act like tiny magnets (see ferromagnetism). Before the current in the electromagnet is turned on, the domains in the iron core point in random directions, so their tiny magnetic fields cancel each other out, and the iron has no large scale magnetic field. When a current is passed through the wire wrapped around the iron, its magnetic field penetrates the iron, and causes the domains to turn, aligning parallel to the magnetic field, so their tiny magnetic fields add to the wire’s field, creating a large magnetic field that extends into the space around the magnet. The larger the current passed through the wire coil, the more the domains align, and the stronger the magnetic field is. Finally all the domains are lined up, and further increases in current only cause slight increases in the magnetic field: this phenomenon is called saturation. When the current in the coil is turned off, most of the domains lose alignment and return to a random state and the field disappears. However some of the alignment persists, because the domains have difficulty turning their direction of magnetization, leaving the core a weak permanent magnet. This phenomenon is called hysteresis and the remaining magnetic field is called remanent magnetism. The residual magnetization of the core can be removed by degaussing. About Electrmagnetic Breaks Electromagnetic brakes (also called electro-mechanical brakes or EM brakes) slow or stop motion using electromagnetic force to apply mechanical resistance (friction). The original name was “electro-mechanical brakes” but over the years the name changed to “electromagnetic brakes”, referring to their actuation method. Since becoming popular in the mid-20th century especially in trains and trolleys, the variety of applications and brake designs has increased dramatically, but the basic operation remains the same. Both electromagnetic brakes and eddy current brakes use electromagnetic force but electromagnetic brakes ultimately depend on friction and eddy current brakes use magnetic force directly.
Block Diagram:
Advantages: • Low cost breaking as compare to other available systems. • Need less space • Dissipate less thermal noise. • Can be easily implemented
Applications: • Breaking system in Vehicles • Breaking system in Machines • Breaking system in toys • Movements in Robotics Accesories
Future Scope of projects: • Project is made future point of view. In future companies are manufacturing Intelligent electronic Chip based vehicle. This electromagnetic system could be easily controlled with electronics system. • Few more improvements also possible in this project. Like slippage calculations and acceleration problems. We will try to solve after testing of project.