Automatic Brake Failure Indicator and Over Heating Alarm

ISSN 2321 3361 © 2016 IJESC

Research Article

Volume 6 Issue No. 7

Automatic Brake Failure Indicator and Over Heating Alarm Dr.N.Venkatachalapathi1, V. Mallikarjuna 2 Professor and Head 1, Assistant Professor 2 Department of Mechanical Engineering, Annamacharya Institute of Technology & Science, Rajampet, A.P –  A.P  –  India  India Abstract: The braking system system of a car is undoubtedly one of its more important important features. The aim of this work is to create a better braking system with indicator. indicator. Brake failure occurs occurs only because of worn out of brake shoe and cut in l iner. It consists of two sensors. One sensor is connected connected with the the brake shoe. The other sensor is the the brake liner. The signal from the two sensors is given to a microcontroller. microcontroller. When the brake shoe is worn out, the sensor senses signal to the microcontroller. microcontroller. Also if the brake liner is cut, cut, the sensor sends signal to the microcontroller. microcontroller. The microcontroller microcontroller analyses the signal and operates the the corresponding indicator. indicator. It nothing wrong, the vehicle will move and if any one critical, the vehicle will stops and the screen shows the indication of brake failure. Since this indicates the status of the brake, the user can identify the condition of the brake and thus limiting the chances of malfunction. Key Words: Anti Breaking system, Sensors, Microcontroller . I. INTRODUCTION Car safety is the avoidance of automobile accidents or the minimization of harmful effects of accidents, in particular as  pertaining to human life and health. Special safety features have been built into car’s  car’s  occupants only, and some for the safety of others. We have pleasure in introducing our new  project “automatic head “automatic head light dim/bright controller and engine over heat alarm” which  which   is fully equipped by sensors circuit, dim/bright light and engine over heat alarm circuit. It is genuine project which is fully equipped and designed for automobile vehicles. This forms an integral part of best quality. This product underwent test in our automobile vehicles and it is good. The major components of the project are follows  Frame  Battery  IR sensor circuit In this Project we are using control unit to check the Brake condition and Engine heat. Here we are sending the signal voltage through the Brake Wire from one end to other end. At the other end in the wheel the signal conditioning unit checks that whether the signal voltage in the Brake wire is available or not. The braking system of a car is undoubtedly one of its more important feature. The aim of this work is to create a better  braking system system with indicator. Brake failure occurs only  because of worn out of brake shoe and cut in liner. It consists of two sensors. One sensor is connected with the brake shoe. The other sensor is the brake liner. The signal from the two sensors is given to a microcontroller. When the brake shoe is worn out, the sensor senses signal to the microcontroller. Also if the brake liner is cut, the sensor sends signal to the microcontroller. The microcontroller analyses the signal and operates the corresponding indicator. It nothing wrong, green indicator will glow and if any one critical, red indicator will glow. If the brake is failure in running time, an alternate brake International Journal of Engineering Science and Computing, July 2016

will be operated by the microcontroller automatically. This  prevents unnecessary unnecessary accident. Since Since this indicates the status of the brake, the user can identify the condition of the brake and thus limiting the chances of malfunction Block diagram

Figure 1.1 Block diagram Back Ground Though the world is getting modernized, we have to face so many problems. One of such problems is accidents. One of the thing that everyone tried to avoid is while traveling is accidents, and sometimes it is inevitable. Now- a-days we can see accidents in every nook and corner of the world. It results in the death of thousands of lives. In foreign countries they take remedial measures for the prevention of accidents but our country like India takes less action against the prevention of accidents.. When the driver brakes they are actually pushing a  plunger into the master cylinder, which in turn pushes brake fluid through tubes and hoses to brake all the moving units in the vehicle. So many other devices are there to predict brake

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failure like United States patent 3711827, United States patent 3914734, etc. The United States patent 3711827 is a self-test incorporated to determine if the warning light is operated  properly. But my project can indicate brake failure and the function of the brake whenever the brake is applied and it is less expensive compared to other products. Ground Clearance Whenever we buy cars we often discuss the fuel economy, style, features, colour, price and all that. But unless widely  publicized, people hardly care to look at the physical specs of the car - in particular the ground clearance. Ground clearance is a factor mostly discussed when someone is buying low level cars. Indeed Luxury cars are known for their low stance and low ground clearance. Now, anyone or any website will tell you that ground clearance is the "minimum distance between the ground/road and the lowest  part of the car". And then manufacturers publish the ground clearance figures such as 160 mm or 170 mm or 180 mm.

Figure 1.5 Demonstration of ground clearance of suspension car

In our concept car the suspension of the car allow minimum of 600 mm ground clearance or even beyond that  becomes a major success factor of the model. In the case of Indian roads the vehicles which have more than 200 mm of ground clearance is appropriate for ride in urban as well as in r ural areas. Description Brake failure indicator is a device used to avoid accidents and it gives an early indication of brake failure. Of all the system that make up a vehicle, the brake system might just be important. If a force is exerted on the piston putting pressure on the fluid confined in the left hand container, the fluid is forced out through the narrow tube at the bottom and into the right hand container, exerting a force on the second piston, forcing it to move upward. The circuit can be assembled on any general purpose PCB or perforated board. The audio indicator is black in color. It is connected on the right side of steering. Both LED’s are red in color.

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The main constituent parts are: IR SENSORS Diode Resistor Capacitor  Buzzer 

International Journal of Engineering Science and Computing, July 2016

Components Required S. Component No 1 Diode 2 IC

3

Resistor

4

Capacitor

5

Switch

6

LED

7 8

Buzzer DC Socket

Specification

Quantity

IN4007 7812 CA 3140  NE555 10K 100K 470Ω 470K 1000µF,25V 100µF,25V 10µF ,25V 0.01µF 0.02µF Brake Switch Ignition Switch Red LED Green LED Plastic 12v

2 2 1 1 5 1 2 1 2 1 2 1 1 1 1 1 1 1 1

Components Description It is a complete standalone voltage regulator. We only need to use 2 capacitors. One on the input and second one on the output of 7812 in order to achieve clean voltage output and even these capacitors are optional to use. To achieve 12v 1A current, 7812 should be mounted on a good heat sink plate. Thanks to the transistor like shape of 7812 which makes it easy to mount on. 7812 is a famous IC which is being widely used in 12V voltage regulator circuits. Truly speaking a heat sink  plate. 7812 has built in over heat and short-circuit protection which makes it a good ch oice for making power supplies. In electronics markets, 7812 is sold under various names such as 7812a, 7812act, 7812t and lm7812. All of them are almost identical with a little to no differences at all. 7812 input voltage range is 14V to 35V. Exceeding the voltage range may damage the IC. Given bellow is 7812 pin diagram to make the  pin out connections clear in case you want to do some experiments. Infra Red Obstacle Detection Sensor In the system we are using 5mm IR SENSORS as an early warning system that also made it economic in design and simple in implementation. Infrared radiation is the portion of electromagnetic spectrum having wavelengths longer than visible light wavelengths, but smaller than microwaves.

An IR sensor Roughly from 0.75µm to 1000 µm is the infrared region. Infrared waves are invisible to human eyes. The wavelength region of 0.75µm to 3 µm is called near infrared, the region

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from 3 µm to 6 µm is called mid infrared and the region higher than 6 µm is called far infrared.

switches, frequency divider, capacitance measurement,  pulse-width modulation (PWM) and so on. Astable  –   free running mode: the 555 can operate as an oscillator.  Uses include LED and lamp flashers, pulse generation, logic clocks, tone generation, security alarms,  pulse position modulation and so on. Bistable mode or Schmitt trigger: the 555 can operate as a flip-flop, if the DIS pin is not connected and no capacitor is used. Uses include bounce free latched switches. LED A light emitting diode is a semiconductor diode that emits light when the electric current is applied in the forward direction of the device, as in the simple LED circuit. The effect is a form of electroluminescence where incoherent and narrow spectrum light is emitted from p-n junction. LED’s are widely used as indicator lights on electronic devices and increasingly in higher power applications such as flashlights and area light. The colour of emitted light depends on the composition and condition of semiconductor material used and infrared, visible or ultraviolet .In brake failure indicator, the LED is used for indication. 

7812 pin diagram If you hold upside down (pins up) and the IC number is facing you then the left pin will be the voltage regulator output, the centred pin will be ground and the right pin will be the voltage input pin. Under my experience, the maximum safe current you can get from one 7812 IC is 1A. If you need more  power then there are a few ways to do so. More than one 7812 can be used in parallel in order to achieve more than 1A current but output voltage of each 7812 can slightly vary resulting in unbalanced load on all of them. This can result in load balancing issues and can damage the IC carrying most current. However there is a way to overcome this problem. I have given bellow a schematic diagram in which two 7812 ICs are attached together and both of them are carrying almost equal load. At least the current difference is not too much to damage any IC IC 3140 The CA3140A and CA3140 are integrated circuit operational amplifiers that combine the advantages of high voltage PMOS transistors with high voltage bipolar transistors on a single monolithic chip. The CA3140A and CA3140 BiMOS operational amplifiers feature gat e protected MOSFET (PMOS) transistors in the input circuit to provide very high input impedance, very low input current, and high speed  performance. The CA3140A and CA3140 operate at supply voltage from 4V to 36V (either single or dual supply). These operational amplifiers are internally phase compensated to achieve stable operation in unity gain follower operation, and additionally, have access terminal for a supplementary external capacitor if additional frequency roll-off is desired. Terminals are also provided for use in applications requiring input offset voltage nulling. The use of PMOS field effect transistors in the input stage results in common mode input voltage capability down to 0.5V below the negative supply terminal, an important attribute for sin- gle supply applications. The output stage uses  bipolar transistors and includes built-in protection against damage from load terminal short circuiting to either supply rail or to ground. 555 IC The 555 Timer IC is an integrated circuit (chip) used in a variety of timer,  pulse generation and oscillator applications. The circuit arrangement of the 555 is said to be even more common, being incorporated in many single-voltage  Flash and other electrically-erasable ICs where it is the basis for the oscillator driving the charge pump which provides the  programming overvoltage. Depending on the manufacturer, the standard 555 package includes over 20 transistors, 2 diodes and 15 resistors on a silicon chip installed in an 8-pin mini dual-in-line package (DIP-8). Variants available include the 556 (a 14-pin DIP combining two 555s on one chip), and the 558 (a 16-pin DIP combining four slightly modified 555s with DIS & THR connected internally, and TR falling edge sensitive instead of level sensitive). The 555 has three operating modes Mono stable mode: in this mode, the 555 functions as a  "one-shot" pulse generator. Applications include timers, missing pulse detection, bounce free switches, touch International Journal of Engineering Science and Computing, July 2016

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Figure 2.1.2(a) LED is on i.e. no any obstacle is present When the brake is applied, the green LED blinks and the  piezo buzzer beeps for around one second if the brake system is intact. If the brake fails, the red LED Glows and the buzzer stop beeping. Diode A diode is a device that permits current flow  predominantly in only one direction. Most semiconductor diodes are made from germanium or silicon. A diode has two leads, an anode and a cathode. The cathode is often marked by a band at one end is the lead by which conventional current leaves the diode when forward biased. There are several types of diode, each with features that suits a particular job. In brake failure indicator, the inverting input is connected to the brake switch through diode and resistor. Buzzer A buzzer or beeper is a signaling device usually electronic. These devices are used in automobiles, household appliances such as microwave oven. It consists of a number of switches or sensors connected to a control unit that determines if and which button pushed or a present time has lapsed, sounds a warning in the form of an intermittent buzzing or beeping sound. Buzzer or beepers are output transducers converting electrical energy into sound. They contain an internal oscillator to produce the sound which is set at about 400 Hz for buzzers and about 3 KHz for beepers. In brake failure indicator, when

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the brake is applied th e green LED blinks and the buzzer beeps for one second and if the brake fails, the buzzer stops beeping. Thus the buzzer functions as an indicator of brake failure.

Figure 2.1.2(b) Buzzer Resistor A resistor is a two terminal passive electronic component which implements electrical resistance as a circuit element. When a voltage is applied across the terminals of a resistor, a current I will flow through the resistor in direct proportion to that voltage. This constant of proportionality is called conductance. The reciprocal of the conductance is known as the resistance R, since, with a given voltage V, a larger value of R further “resists “the flow of current I as given by ohm’s law: I = V/R Resistors are common elements of electrical networks and electronics circuits and are ubiquitous in most electronics equipment’s. Practical resistors can be made of values compounds and films, as well as resistance wire (wire made of a high-resistivity alloy, such as nickel-chrome).Resistors are also implemented within integrated circuits, particularly analog devices, and can also be integrated into hybrid and printed circuits. Capacitor Capacitor (formerly known as condenser) is a device for storing electric charge. The forms of practical capacitors vary widely, but all contain at least two conductors separated by a nonconductor. Capacitor used as parts of electrical system, consist of metal foils separated by a dielectric (insulator). Energy is stored in the electrostatic field. An ideal capacitor is characterized by a single constant value, capacitance, measured in farads. Capacitors are widely used in electronic circuits, for  blocking direct current while allowing alternating current to  pass, in filter network, for smoothing the output of power supplies, in the resonant circuits that tune radios to particular frequencies and for many other purposes. Main and Secondary Power Supply Main power supply is for complete circuit and the secondary power supply is only for the Led and IR circuit activation. Specification of both the supplies are –  Main power supply  –  1 Batteries i.e. 12 V and 1.5 ampere

Figure 2.1.2(c) Main Power Supply Batteries International Journal of Engineering Science and Computing, July 2016

Secondary Power Supply 9V battery

Figure 2.1.2(d) Secondary Power Supply Joystick for Controlling the Vehicle The below diagram shows the joystick and its designing, wiring done in respect of the vehicle

Figure 2.1.2(e) Joystick for the vehicle Soldering

Soldering is the process of joining two or more similar or dissimilar metals by melting another metal having lower melting point. Soldering Fluxes In order to make the accept the solder readily; the components terminals should be free from oxides and other obstructing films. Soldering flux cleans the oxides from the surface of the metal Zinc Chloride, ammonium Chloride and Rosin are the commonly used fluxes. Solder Solder is used for joining two or metals at temperature  below their melting point. The popularly used solders are alloy of Tin (60%) and Lead (40%) that metals at 375f and solidifies when it cools. Soldering Iron It is used to melt the solder and apply at the joints in the circuit. Block Diagram of IR Circuit A typical system for detecting infrared radiation is given in the following block diagram:

Infrared Source All objects above 0 K radiate infrared energy and hence are infrared sources. Infrared sources also include blackbody radiators, tungsten lamps, silicon carbide, and various others. For active IR sensors, infrared Lasers and LEDs of specific IR wavelengths are used as IR sources. Transmission Medium Three main types of transmission medium used for Infrared transmission are vacuum, the atmosphere, and optical

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fibers. The transmission of IR  –   radiation is affected by  presence of CO2, water vapor and other elements in the atmosphere. Due to absorption by molecules of water carbon dioxide, ozone, etc. the atmosphere highly attenuates most IR wavelengths leaving some important IR windows in the electromagnetic spectrum. Optical Components Often optical components are required to converge or focus infrared radiations, to limit spectral response, etc. To converge / focus radiations, optical lenses made of quartz, CaF2, Ge and Si, polyethylene Fresnel lenses, and mirrors made of Al, Au or a similar material are used. For limiting spectral responses, band pass filters are used. Choppers are used to pass interrupt the IR beams. Infrared Detectors Various types of detectors are used in IR sensors. Important specifications of detectors are  Photosensitivity or Responsivity: Responsivity is the Output Voltage/Current per watt of incident energy. Higher the better.   Noise Equivalent Power (NEP): NEP represents d etection ability of a detector and is the amount of incident light equal to intrinsic noise level of a detector.  Detectivity (D*: D-star): D* is the photosensitivity per unit area of a detector. It is a measure of S/N ratio of a detector. D* is inversely proportional to NEP. Larger D* indicates better sensing element. In addition, wavelength region or temperature to be measured, response time, cooling mechanism, active area, no of elements, package, linearity, stability, temperature characteristics, etc. are important parameters which need attention while selecting IR detectors. Signal Processing Since detector outputs are typically very small,  preamplifiers with associated circuitry are used to further  process the received signals. We used these sensors as a detector which provides early detection. Process Description Brake failure indicator is a device which is used to avoid accidents. The brake failure indicator circuit is a circuit that constantly monitors of the condition of brakes and gives an audio visual indication. When the brake is applied the green LED blinks and the piezo buzzer beeps for around one second if the brake system is intact. If brake fails the red.The circuit will work only in vehicles with negative grounding. It also gives an indication of brake switch failure. In hydraulic brake systems of vehicles; a brake switch is mounted on the brake cylinder to operate the rear brake lamps. The brake switch is fluid operated and doesn’t function if the fluid pressure due to leakage. The fluid leakage cannot be detected easily unless there is a severe pressure drop in the  brake pedal. This circuit sensor the chance of brake failure by monitoring the brake switches and reminds you of condition of  brake every time the brake is a pplied. The circuit comprises of IC’s, seven resistors, seven capacitors, two LED, Tw o diodes and a buzzer. The circuit uses an op-amp (IC 2) as voltage comparator and timer in constable configuration for alarm. IC International Journal of Engineering Science and Computing, July 2016

2 senses the voltage level across, the brake switch. Its non  –  inverting input gets half the supply voltage through potential divider resistors R3 and R4 of 10 Kilo  –   ohms each. The inverting input of IC2 is connected to brake switch through diode DI, ICI and resistor R2. It receives a high voltage when the brake is applied.  Normally, when the brake is not applied, the output of IC2 remains high and the red LED glows. Resistor R1 is used for the input stability of IC2. ICI and CI provide a ripple-free regulated supply to the inverting input of IC2. IC3 is wired as a mono stable to give pulse output of one second. Timing elements RT and C4 make the output high for one second to activate the buzzer and LED2. Usually the trigger pin of IC3 is high due to R6 and the buzzer and LED2 remains off. When the brake pedal is pressed, pin 2 of IC2 gets a higher voltage from the brake switch and its output goes low to switch off the red LED. When there is a pressure drop in the brake system due to leakage, the pressure sensor works LED1 remains ‘on’ And the buzzer does not sound when the brake is applied. The circuit can be assembled on any general purpose PCB or  perforated board. The circuit can be powered form the vehicle’s battery. The circuit requires well -regulated power supply to avoid triggering while the battery is charging from the dynamo. IC4, C6 and C7 provide regulated 12V to the circuit. The power supply should be taken from the ignition switch and the circuit ground be clamped to the vehicles body. A bicolor LED can be used in place of LED1 and LED2 if desired. Anti Collision System The Anti – Collision device is a detection device meant to  be incorporated into cars for the purpose of safety. As opposed to the anti – collision devices present in the market today, this system is not designed to control the vehicle. Instead, it serves as an alert in the face of imminent collision. The device is intended to find a way to implement a minimum spacing for cars in traffic in an affordable way. It would also achieve safety for the passengers of a moving car. The device is made up of an infrared transmitter and receiver.

Figure 3.1 Grid formation by transmitted rays of IR sensor

Also incorporated into it is an audio visual alarm to work in with the receiver and effectively alert the driver and/or the  passengers. The device works by sending out streams of infrared radiation and when these rays are seen by the other equipped vehicle, both are meant to take the necessary precaution to avert a collision. The device would still sound an alarm even though it is not receiving infrared beams from the oncoming vehicle. This is due to reflection of its own infrared beams. At the end of the design and testing process, overall system was 8675

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implemented with a constructed work, tested working and  perfectly functional.

Figure 3.1(b) Transmission and reception of the waves by IR sensors This is due to reflection of its own infrared beams. At the end of the design and testing process, overall system was implemented with a constructed work, tested working and  perfectly functional. Circuit Diagram

 braking system with indicator. Brake failure occurs only  because of worn out of brake shoe and cut in liner. It consists of two sensors. One sensor is connected with the brake shoe. The other sensor is the brake liner. The signal from the two sensors is given to a microcontroller. When the brake shoe is worn out, the sensor senses signal to the microcontroller. Also if the brake liner is cut, the sensor sends signal to the microcontroller. The micro controller analyses the signal and operates the corresponding indicator. It nothing wrong, green indicator will glow and when break failure signal fault detected red indicator will glow and automatically activated external mechanical brakes used to avoiding the accident. The system automatically stops vehicle, when the IR sensor detecting the  parts of the operator inside the machine. How Brake Failure Works? As drivers, we need both of these features as much as we need to breathe in and out. If you've ever been in a vehicle that did not stop, you know the sheer terror that brake failure can cause. Whether your vehicle is equipped with disc or drum  brakes, you expect them to work when you hit the brake pedal. Brakes can't talk -- or can they? If you're not distracted with chatter or music, you might hear your brakes trying to tell you when something's wrong. Brakes have their own language; they squeal, click, squeak and grind. You need to listen carefully to their noises rather than ignore them and hope the sounds will magical.

Figure 3.2 circuit diagram

The circuit uses an op-amp IC CA3140 (IC2) as voltage comparator and timer NE555 (IC3) in constable configuration for alarm. Voltage comparator IC2 senses the voltage level across the brake switch. Its non-inverting input gets half the supply voltage through potential divider resistors R3 and R4 of 10 kilo-ohms each. The inverting inputs of IC2 are connected to the brake switch through diode D1, IC7812 (IC1) and resistor R2. It receives a higher voltage when the brake is applied.  Normally, when the brake is not applied, the output of IC2 remains high and the red LED glows. The output of IC2 is fed to trigger pin 2 of the mono stable through coupling. Resistor R1 is used for the input stability of IC2. IC1 and Cl provide a ripple-free, regulated supply to the inverting input of IC2. 1C3 is wired as a mono stable to give pulse output of one second timing elements R7 & C4 make the output high for one second to activate buzzer and LED 2 usually the trigger pin of IC 3 is high due to R6 & Buzzer and LED2 remains of when the brake  pedal is pressed pinto of IC2 gets higher voltage from the  brake switch and its output go slow to switch of the red LED. The low output IC2 gives a short negative pulse to the mono stable through C2 to trigger it. This activates buzzer and Led 2 indicate that brake system is working. When there is a pressure drop in the brake system due to leakage, LED1 remains on and the buzzer does not sound when the brake is a pplied. Working Principle The braking system of a car is undoubtedly one of its more important feature. The aim of this work is to create a better International Journal of Engineering Science and Computing, July 2016

Figure 3.3(a) Disc brake

The easiest way you can avoid brake failure is by maintaining the vehicle regularly and being attentive to any changes in performance. Because a vehicle's brake system involves many components along the entire length of the vehicle, any number of things can go wrong. Calipers, drums and brake pads, Let's say that despite your attentive care of th e vehicle, the brakes begin to fail. What dangers might you and your passengers face, and h ow can you prepare for them? What will you do if you are towing a boat or trailer and experience  brake failure? How can a runaway truck ramp help if your  brakes stop working? In this article, we'll investigate the answers to these questions, explaining everything you need to know along the way. Brake Pads Working There's a lot more to effectively using your car's braking system then simply stomping on the pedal when a squirrel darts out in front of you. The braking systems of cars, trucks and motorcycles are made up of a number of parts that translate the driver's actions into physical force that stops the car. One of those brake parts is your vehicle's brake pads. Brake pads are a key brake part because they are the component that contacts and applies pressure and friction to a

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vehicle's brake rotors -- those flat, shiny discs that you can sometimes see just behind the wheels of some vehicles.

Figure 3.3(b) disc pads

The pressure and friction applied to the brake rotor is what slows and stops the wheel. Once the wheels stop turning, the vehicle stops moving, too. Though the role of brake pads as  braking parts is pretty simple, the brake pads themselves are anything but. Because of how fast a vehicle's wheels rotate and how much a typical car or truck weighs, brake pads undergo extreme stress every time you slow down or come to a stop. Think about it: Would you want to grab and hold on to a heavy metal disc that was spinning really fast? Imagine slowly squeezing that disc until the vehicle rolls to a halt -- it's a thankless job, but brake pads do it repeatedly for thousands and thousands of miles without complaint. Brake Controllers Working If you've ever gone roller skating at the rink with a large group of friends, you might very well have started a train. With everyone in single file and holding onto the person in front of him or her, the train continues in a circle around the rink. As long as everyone skates together at the same relative speed, the line will move along safely.

Figure 4.1(a) Emergency brake assist Dynamic Stability and Traction Control (DSTC) DSTC makes driving on twisty and slippery road conditions safer, by using sensors to detect whether any of the wheels is losing traction. DSTC has the ability to cut power in a flash, helping the car to regain its grip. If in any case the car shows a tendency to skid the system automatically slows the  particular wheels to help maintain control.

Figure 4.1(b) Brake assist Electronic Brake Distributed (EBD) EBD makes sure that the braking forces of the car are distributed between the front and the rear brakes in order to optimize braking efficiency.

Figure 3.3(c) brake controller

The group can't go on skating in circles forever, of course. So when someone needs to take a break, the best way the whole train can slow down at the same time is if the person at the front of the line sends a signal to rest of the skaters to slow down. This way, each skater stops at about the same time, avoiding any collisions. If the front skater had decided to stop on his own without letting those behind him know of his decision, the full force of the train's momentum would cause his fellow skaters to crash into him, creating a massive pileup and probably tripping up any nearby strangers. You can think of a truck towing a trailer in a similar way. IACCIDENT AVOIDANCE SYSTEMS Emergency Brake Assist (EBA) In an emergency, many people do not depress the brake  pedal hard enough. EBA senses an emergency braking situation and helps the driver to reduce speed in the shortest distance possible.

International Journal of Engineering Science and Computing, July 2016

Figure 4.1(c) Electronic Brake Distribution Anti-lock Braking System (ABS)

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With ABS you can brake as hard as you can and steer yourself to safety without the fear of wheels locking up and skidding.

Figure 4.1(d) Anti-Lock braking system Blind Support Information System (BSIS) Using cameras set just below the outer rear view mirrors the BSDS tell you if there is any vehicle in your blind spot.

Figure 4.1(e) Blind Spot information system Night Vision Driving during the night becomes safe than ever with the night vision where one can see clearly on the control display even in pitch black. Thanks to infra-red technology

Figure 4.1(f) Night vision Rules and Regulations Several rulemaking committees and government safety authorities have addressed the deficiencies in the existing elevator regulations and have proposed revisions to the elevator safety codes. The report from the American Society of Mechanical Engineers - A17 Mechanical Design Committee on "Cars ascending into the building overhead,"-dated September 1987, contained the types of failures that could result in elevators accelerating into overhead structure and an analysis of the  possible solutions. In addition, a proposal to the A17.1 Committee for a new code Rule 205.6 was introduced as follows: Rule 205.6 ("Prevention of over speeding car from striking the overhead structure"): All traction elevators shall be  provided with a means to prevent an ascending car from

International Journal of Engineering Science and Computing, July 2016

striking the overhead structure. This means shall conform to the following requirements: 1. Prior to the time when the counterweight strikes its buffer, it shall reduce the speed of the car to the speed for which the counterweight buffer is designed. 2. It shall not develop an average retardation of the car in excess of 32.2 ft./s2 (9.81 m/s2) during the stopping  phase. 3. It shall be a mechanical means independent of the driving machine brake. 4. It shall prevent over speeding of the elevator system through the control of one or more of the following: a. Counterweight  b. Car c. Suspension or compensating rope s ystem. This proposed rule is currently under committee review, and consideration has been given to requiring protection to  prevent the car from leaving the landing with the doors opened or unlocked. An ascending elevator car accident occurred at a western Pennsylvania coal mine on February 4, 1987 and caused extensive structural damage and disabled the elevator for two months. Following this accident, the Pennsylvania Bureau of Deep Mine Safety established an advisory committee to determine these devices that are available to provide ascending car over speed protection for new and existing mine elevator installations. The following four protective methods were determined to  be feasible based on engineering principles or extensive mine testing. 1. Weight balancing (counterweight equals the empty car weight). 2. counter weight safeties 3. dynamic braking 4. rope brake. The Pennsylvania Bureau of Deep Mine Safety has approved these four methods and has made ascending car over speed protection mandatory on all existing counterweighted mine elevators within the state of Pennsylvania, effective December 1, 1991. The safety code also addressed the potential risk of injuries to passengers if a failure would cause the car to leave the landing with the door open. This hazard could cause the  passenger to be crushed between the car floor and landing door header. This risk is also present in the down direction. To eliminate the "trapping risk" in both directions, additional  protective means that must detect any un controlled movement of the car are required. Protective Devices Several methods are available to provide ascending car over speed protection. Some methods are feasible only on new installations, and others are easily retrofitted to existing elevators. Three of the most viable solutions ar e presented here for consideration. Counterweight Safeties The obvious method is to install traditional safeties on the counterweight; however, the reliability of this old technology is being questioned. In addition, this m ethod can be difficult to

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install on existing elevators, especially if the counterweight guide rails and brackets need to be replaced to accommodate the additional load forces. Clearances may not be available for the counterweight safeties due to limited shaft way dimensions. There is also a problem with maintaining the safety system under the less than desirable operating environment that is  present in the mine shaft way. Dynamic Braking A second solution used in the United States mining industry is the application of passive dynamic braking to the elevator drive motor. As mentioned earlier, most elevators use direct current drive motors that can perform as generators when lowering an overhauling load. Dynamic braking simply connects a resistive load across the motor armature to dissipate the electrical energy generated by the falling counterweight. The dynamic braking control can be designed to function when the main power is interrupted. Dynamic braking does not stop the elevator but limits the runaway speed in either direction; therefore, the buffers can safely stop the conveyance. Mechanical Modification Prior to testing, several mechanical modifications were required to protect the rope brake system from environmental and mechanical damage. The modifications also reduced the  possibility and the undesirable effect of an air leak in the  pneumatic system. The following modifications were included in the rope brake design: 1. The 200 lbf/m2  rated plastic air hose was replaced with 2,000 lbf/m2  rated metal braided hose with integral couplings. 2. The air hose compression fittings were replaced by stainless steel threaded connectors. 3. All the electrical components were installed in protective enclosures, and the wiring was installed in conduit. 4. A check valve was installed in the compressed air supply line to hold the rope in the applied position once it was set even if air pressure was lost in the air compressor tank. 5. The added check valve required an additional pressure switch to monitor the supply air pressure. The original  pressure switch would n ot detect a pressure loss in the air compressor tank when the check valve was installed. The contacts of the two pressure switches were installed in series. MECHANICAL TESTING Product In order to detect the efficiency and its working of Brake failure indicator, several tests were conducted. Before releasing it as a new product into the market, every product undergo testing. So product testing is essential to verify the working of the product. The test should be decided in order to verify whether the product satisfied all the objectives. With the help of speed test, we can verify the different levels of speed. In order to detect the effect of petrol level on this device, the  petrol level testing is also conducted. The condition of brake is also detected with the h elp of another methods. Therefore, with the help of this tests, we find out whether the “Brake Failure Indicator’ is working properly or not.

International Journal of Engineering Science and Computing, July 2016

Speed Testing With the help of this test, we can confirm that the brake failure indicator is working in all the above conditions. This test was under taken to check the working of brake switch as well as brake failure indicator. From this testing, we find out that whether the speed is high or low, the brake failure indicator is working in all condition. It is working at even low speed also. So from speed test we can confirm that it is working properly. Petrol level Testing: From the above test, we can confirm that the level of petrol does not cause any problem to the condition of brake. Thus the brake failure indicator worked properly at all conditions. Tests were conducted to determine if the rope  brake would operate reliably in the mining environment to  provide ascending car over speed protection. First, accelerated mechanical testing was performed to determine if the braking system could withstand repeated operation without experiencing significant wear or failure. These tests were performed while the suspension ropes were stationary. This testing was conducted at both the mine site installation and in the laboratory. Mine site testing was conducted every 4 hr. Mechanical counters were installed on both the machine brake and the rope  brake to record the total number of operations for each brake. Every 4 hr, the number of times the machine brake had set during the previous 4 hr period was noted, and then, the rope  brake was operated an equal number of times. The mechanical testing concluded after 30 days of around the clock testing. The total number of rope brake operations was 3430. The temperature range varied from 25 to 83°F. One of the rope brake components subjected to wear was the piston ring gasket. This gasket provides the air seal  between the moving piston, which presses against the traveling  brake pad, and the stationary cylinder. An overload test was conducted to determine the integrity of this seal. For the test, 8750 lb (125% of rated load) was loaded onto the car at the bottom of the sh aft. Then, the rope brake was set, and the machine brake was disengaged. The air pressure was released from the air compressor tank, and the air pressure inside the rope brake cylinder was monitored. The load was successfully held stationary for 1 hr. The initial air pressure was 114 lbf/in 2, and after 1 hr, the pressure was 102 lbf/in 2. The pressured reduction may be attributed to an air leak through the check valve or past the piston ring gasket as a result of wear. After 2 mo of testing and 146,836 operations, the rope  brake was disassembled and inspected for wear. The pneumatic  piston ring gasket exhibited minimal wear. Superficial rust was evident where the compressed air entered the rope brake and displaced the lubricant. Over the 70 days of testing, the temperature ranged from 5 to 82°F, and the relative humidity varied from 25 to 100%. At times, thick accumulations of frost build up on the air line  between the magnetic valve and the rope brake cylinder. Therefore, the formation of ice inside the compressed air lines was possible; however, no adverse effects were observed. Rope Pulse Tachometer Test The brake control logic obtains the speed reference signal from an independent pulse tachometer assembly. The pulse

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tachometer assembly consists of two proximity switches mounted 45 mechanical degrees apart around a rotating rubber wheel. Two sheet metal screws are installed into the rubber wheel on opposite sides (180° apart). The rubber wheel is friction driven by the suspension ropes. A spring tension arm maintains pressure between the rubber friction wheel and suspension ropes. Electrical pulses are generated as the screw heads pass beneath the proximity switches. This pulse train is interpreted by the brake control box to obtain the speed of the elevator. Speed Relay Input Test The brake control logic also monitors a speed relay to determine if the elevator should be running. For this installation, the elevator speed relay RL2 is monitored by the  brake control logic. The normally closed contact of RL2 opens when the elevator reaches 60% of the rated speed. The speed contact serves as a check on the rope tachometer. When RL2 is opened, the brake control should be receiving a signal from th e rope tachometer. The rope brake and machine brake set if the tachometer fails for any reason to produce a signal when the elevator control has a run command. Motor Contactor Input Test The M contact is the main motor contactor that closes to supply armature current to the drive motor. When the M contact is open, power is removed from the elevator drive motor and the machine brake is set. An auxiliary contact on th e M contactor drives the M x  relay, which then drives the M a relay. The normally open contact on the M a relay is monitored  by the rope brake control logic. Therefore, when the Ma contact is open, the elevator should be stationary or coming to a stop. Pressure Switch Test The rope brake is equipped with two pressure switches to monitor the air pressure on each side of th e added check valve. The contacts for each pressure switch are connected in series. Therefore, both must be closed to provide power to the SR relay (fault string) and allow the elevator to run. According to the previously discussed test results, the pressure switch contacts close when the air pressure is greater than 54 lbf/in 2. When low pressure is sensed on either side of the check valve, the SR relay drops out, which opens the safety fault string, thereby removing the drive power and causing the machine  brake to set. The brake control logic did not detect the shorted failure of the pressure switch during laboratory testing. Therefore, a mechanical limit switch was required to be installed on the rope brake to monitor the position of the rope brake pads and assure that the rope brake is released when the elevator is running. Test Button A test button is located on the front panel of the brake control box. The purpose of the button is to test the speedsensing circuitry of the brake control system. If the test button is pressed while the elevator is running at rated speed, a red indicator button is illuminated. During laboratory testing, it was discovered that depressing the test button will defeat the over speed protection of the brake control. As a result of this discovery, the test button was required to be disconnected from International Journal of Engineering Science and Computing, July 2016

the rope brake electronic control and was required to be mechanically disabled. Dynamic Performance Tests The retarding capacity of the Bode rope brake model 580 was tested at the mine site on three occasions over a 6-mo  period. During the test procedure, the elevator motor armature current, field current, armature voltage, speed (analog tachometer feedback), and rope brake cylinder air pressure were monitored and recorded on an eight-channel thermal array recorder. Low Air Pressure Tests A series of tests were conducted with the air compressor motor disconnected from the power source to determine the number of times the rope brake could stop the elevator from the stored pressurized air in the compressor tank. The test were conducted with no car load in the upward direction.

Figure 5.3 Rope Brake Retarding Effort during Low Air Pressure

The stopping distances were calculated from the actual deceleration rates based on an initial speed of 600 ft/min. As expected, the stopping distance increased as the available air  pressure decreased. The rope brake was able to effectively stop the elevator within 82 feet with as little as 30 lbf/in 2 in the air compressor tank. After the rope brake set, only 22lbf/in 2  was available in the air compressor tank. The slight distortion in the curve may be attributed to the varying condition of the suspension rope surface an d initial speed fluctuations. Compound Braking The effect of compound braking is always a concern on elevators equipped with multiple brakes. This elevator is equipped with four independent braking systems: the machine  brake, dynamic brake, rope brake, and safeties. Each system must be individually capable of retarding the elevator. However, deceleration rates in excess of 16 ft/s 2  should not occur when all the braking systems are activated simultaneously. Analysis of the data showed th e greatest deceleration rates were observed when the machine, dynamic, and rope brakes were activated with no car load in the down direction. This compound braking produced a deceleration rate of 13.8 ft/s2, which is considered to be a safe stopping rate.

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The rope brake was also capable of stopping the maximum rated load (7000 lb) traveling down at rated speed. The measured deceleration rate was 5.88 ft/s 2, which translates into a stopping distance of 8.5 ft when traveling at 600 ft/min. The dynamic braking system produces a retarding force  proportional to the speed with an initial deceleration rate of 2.7 ft/s2. The dynamic braking system begins retarding the elevator immediately since the motor contactor connects a resistor across the motor armature instead of opening the circuit and allowing the counterweight to accelerate downward. The dynamic braking effort is reduced as the speed decreases until an equilibrium is reached between the retarding effort and the load forces, resulting in a steady-state speed [6]. Dynamic braking is an excellent system to assist the mechanical brake since the dynamic brake limits the initial overspeed conditions without having a significant compound  braking effect.

[5] J. A. Nederbragt, "Uncontrolled Speed, Up and Down," Elevator World, Dec. 1985. [6] T.D. Barkand, W.J. Helfrich, “Application of Dynamic Braking to Mine Hoisting Systems", IEEE Transactions on Industry Applications, September / October 1988. [7] J.A. Nederbragt, "Rope Brake: As Precaution Against Overspeed," Elevator World, July 1989. [8] -----, "Report of Test Results" conducted by TNOIWECO, Delft Tech. Univ., June 7, 1989.

Scope of the Paper The brake failure indicator circuit is designed for avoiding accidents due to brake failure. If you can grasp the necessary force and the durability that brakes require to stop tones of moving metal, you can understand how brake malfunctions can occur. So many things can cause brake failure. There are something that we all take for granted, the brake on our vehicles.  It is very unusual for a vehicle to suffer total failure of the braking system. Though it has so many limitations, this equipment is very effective to detect brake failure and it will find great scope in future. CONCLUSION We are proud to express our delight as the project we embarked upon is successfully finished within the target date. The project gave us more confidence that we will be able to  put in practice, whatever theoretical knowledge. we gained during our course of study till now. If really persuades us to do more and more, perhaps in better way in our future. Brake failure indicator is a early warning system. it constantly monitors the condition of the brake and give audio visual indication. REFERENCES [1] A17 Mechanical Design Committee Report on Cars Ascending into the Building Overhead, ASME, Sept. 1987.

[2] W.J. Helfrich, "Island Creek Coal Company V.P.-5 Mine," MSHA, Mine Electrical Systems Division Investigative Report No. C080978, August 1978. [3] T.D. Barkand, "Investigation of the Accident and Installation and Testing of Dynamic Braking on the Main Elevator at Duquesne Light, Warwick Mine, #3 North Portal," MSHA, Mine Electrical Systems Division Investigative Report C-052287-12, May 1987. [4] C. E. Valhovic, "Rational for New Rules, in CSA-B44 Safety Code for Elevators," Elevator World, July 1989.

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