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1 Wi Lights - A Wireless Solution To Control Headlight Intensity Amiya Kumar Tripathy 1, Deepali Kayande 2, Joel George 3, Jerome John 4, Bejoy Jose 5 Department of Computer Engineering, Don Bosco Institute of Technology, Mumbai, India 2 kayande.deepali@gmail.com, 1 tripathy.a@gmail.com, 3 joelgeorge46@gmail.com, 4 jeromejohn445@gmail.com, 5 bejoyjose1993@gmail.com Abstract - A number of factors are considered during theanalysisof automobile transportation with respect to increasing safety. One of the vital factors for night-time travel is temporary blindness due to increase in the headlight intensity. While headlight intensity provides better visual acuity, it simultaneously affects oncoming traffic. This problem is encountered when both drivers are using a higher headlight intensity setting. Also, increased speed of the vehicles due to decreased traffic levels at night increases the severity of accidents. In order to reduce accidents due to temporary driver blindness, a wireless sensor network (WSN) based controller could be developed to transmit sensor data in a faster and an efficient way between cars. Low latency allows faster headlight intensity adjustment between the vehicles to drastically reduce the cause of temporary blindness. An attempt has been made to come up with a system which would sense the intensity of the headlight of the oncoming vehicle and depending on the threshold headlight intensity being set in the system it would automatically reduce the intensity of the headlight of the oncoming vehicle using wireless sensor network thus reducing the condition of temporary blindness caused due to excessive exposure to headlights. Keywords: WSN, Microcontroller, Communication, Driver Detection Systems, Headlight Detection System. I. INTRODUCTION Around 33% of all the traffic accidents generally occur during night time travel inspite of the fact that during night time the number of vehicles fleeting through the roads is comparatively very much lower as compared to the number of vehicles during the daytime[1]. Also, the accident taking place during the night time also shows a trend of having higher proportion of fatalities. Earlier research done by researchers show that the potential risk associated with getting killed in a road accident is as much as twice of that which occur during the day time travel. All these alarming facts show that the problem of temporary blindness caused due to elevated headlight intensity is very severe with respect to the number of fatalities which occur during night time travel[2]-[4]. In order, to avoid these conditions which arise due to elevated light intensity a particular system is attempted to be developed which would cater to the above problem. The current headlights which are present in the market do have a setting to manually reduce the intensity of their own headlights. Any type of a particular headlight in the vehicle whether it is a headlight or tail light has its own intensity level setting which changes with the different variety of headlight being used in the system[2]. The different type of headlight which may include the halogen headlights, LED headlights, tungsten filament headlights, etc. consists of different levels of headlight intensity. Either of these variety of lights being used in the headlight or tail light their maximum intensity of light obviously affects the drivers. The current headlights being used in the vehicles only have a setting by which the user can manually set the intensity level[6]. The problem which is expected to be tackled by the system is the problem of temporary blindness which is caused due to the elevated headlight intensity of the vehicles. This in turn would eventually lead to reduced number of accidents due to temporary blindness especially due to night time travel. This scenario could be effectively tackled by reducing the intensity of the headlights simultaneously which would completely avoid the problem of temporary blindness. This could be implemented by developing a system which would sense the headlight intensity of the oncoming vehicle and sensing the headlight intensity it should be capable of reducing the intensity. If a system could be developed which would regulate the intensity of the oncoming vehicle and vice versa, the problem could be effectively handled. Thus in this way the problem of temporary blindness could be systematically tackled. The existing system of headlights which are currently being used in the vehicles do not have a mechanism by which they can sense or automatically reduce the intensity setting of the headlights or tail lights[3]-[4]. With respect to this condition, earlier a solution was thought upon, by which the same idea of automatically reducing the intensity of headlights was thought to be implemented. A slight difference of changing the intensity of the headlight, not of the oncoming vehicle as the discussed in the earlier section but of the same vehicle in which the system is incorporated. This idea was thought upon during the earlier research phase of the system /15/$ IEEE

2 The above mentioned system had certain flaws. The system mentioned above had the same functionality as the final architecture which will be discussed later, but the flaw was associated with the regulation of the headlight intensity of the same vehicle. To understand that a scenario can be considered wherein, two vehicles during night time travel in which the above mentioned system is incorporated are supposed to be moving in the opposite direction, i.e. towards each other. The system in one vehicle will sense the intensity of the light of the oncoming vehicle and reduce the intensity of its own. In this case, the problem of temporary blindness would be avoided for the oncoming vehicle[11]. But with respect to the oncoming vehicle, the headlight intensity of the opposite vehicle is already sensed to be reduced so it would not reduce its own headlight intensity. Thus, still the problem of temporary blindness would still prevail for the other vehicle. So the above system fails to avoid problem of temporary blindness so a new system was thought upon which would sense the intensity of the headlights as in the earlier system but instead of reducing its own headlight intensity with respect to the other vehicle it would reduce the intensity of the oncoming vehicle and vice versa so the problem of temporary blindness is completely avoided. The proposed system which is expected to counter the problem of temporary blindness would sense the intensity of the headlights from the oncoming vehicle in analog form, which would be sent to the analog-to-digital converter (ADC) to convert to digital signals[5]. The Analog to digital converter would send this digital signal to the microcontroller where the threshold intensity level is set. It would compare the received intensity in the digital form to the threshold intensity and send this signal via X-Bee to the other vehicles' system. Once the other system receives the signal via the X-Bee the pulse width modulator in the system would reduce the intensity of the headlight which is connected to it. The same function will be performed by the system incorporated in the other vehicle. The system uses X-Bee transmitter and receiver because the transmission of signal using this is more efficient and faster. A. Background Research II. METHODOLOGY For developing the system which would cater as a solution to the problem of temporary blindness various factors had to be considered as in for developing the architecture. For sensing the light from the headlight of the oncoming vehicle LDRs are used. Similarily, the selection of the correct microcontroller all was an elemental part of the research phase. For converting the analog signal to digital signal usage of ADC is required. In order to proceed with the implementation of the system one would require knowledge of microcontrollers, analog digital converters, X-bee transmitters and receivers, pulse width modulator (PWM), Light Dependent Resistors also the knowledge of programming related to the microcontrollers is required. To begin with the system various research work related to the different types of headlights being used in vehicles along with the intensity of the headlights which is perceivable to human eyes is required. Depending on the headlights being used in the vehicle the threshold intensity i th of the headlights may differ. According to the research during the research phase of the system, depending on the vehicles it was found that there was a similar variance in the type of headlight being used. So, by this it could be concluded that for different headlights the value of threshold intensity will also change. This paper presentation does not deal with the variance in the headlight but is dependent completely on the usage of basic headlights which are used in motorbikes. (As shown in Fig. 1) In bright -light situations (called photopic, using cones),the sensitivity peaks around 550 nm, going from 400 to 700.In the dark, we switch to scotopic vision (rods), centered at 510 nm, going from 370nm to 630nm[7]- [9]. Fig. 1. Graph related to intensities perceivable to human eye In order to develop a system which would sense the light intensity using Wireless Sensor Networks the system was proposed which would use LDRs, Microcontrollers, Pulse Width Modulator, Analog Digital Convertors, by which it would automatically reduce the intensity of the headlight of the oncoming vehicle using wireless sensor network thus reducing the condition of temporary blindness caused due to excessive exposure to headlights. III. PROPOSED SYSTEM The final proposed system which is expected to reduce the problem of temporary blindness would sense the intensity of the headlights from the oncoming vehicle in analog form, which would be sent to the analog-to-digital converter (ADC) to convert to digital signals. The ADC would send this digital signal to the microcontroller where the threshold intensity level is set. It would compare the received intensity in the digital form to the threshold intensity and send this signal via X-Bee to the other vehicles' system. Once the other system receives the signal via the X-Bee the pulse width modulator in the system would reduce the intensity of the headlight which

3 is connected to it. The same function will be performed by the system incorporated in the other vehicle. The system uses X- Bee transmitter and receiver because the transmission of signal using this is more efficient and faster. Also, the X-Bee provides a better range of 100 m which is approximately equal to 300 ft and has a line of sight of approximately 1.6 kms. A. Microcontroller The microcontroller to be used in the system is IC89S52 which belongs to the 8051 family. The function of the microcontroller in the system is to compare the intensity value of the oncoming headlight with the threshold headlight intensity which would be set into the system. The working of the microcontroller is shown in Figure 2. The intensity obtained to the microcontroller is in the form of digital signal. This digital signal is a form of the signal which would be the signal which would be received to the analog to digital converter (ADC) through the LDR (Light Dependent Resistor). Fig. 2. Block diagram of the Working of the Microcontroller [2] The light dependent resistor senses the light intensity from the oncoming vehicle it sends it to the microcontroller which already has the threshold intensity that would be compared and the event is set which will be discussed later in this paper. In accordance with that, the output intensity value would be set and output to the headlights. The onset of the event is said to commence from the moment when the LDR in the system would sense the intensity of the headlight. The X-Bee transmitter and receiver is capable of communicating with the range of approximately 300ft or say 100 m. In order to send signals between the vehicles so as to regulate the intensity of the headlight X-bee transmitter and receiver proves to be elemental as the main cause of developing the system that is to prevent the problem of temporary blindness. B. Analog to Digital Converter (ADC) An analog-to-digital converter (ADC) is a component that converts an analog signal to a digital number or a digital signal that represents a certain amplitude of the signal. The function of the ADC is to convert the analog signal sensed by the LDR to digital which is given as input to the microcontroller. An ADC is defined by its bandwidth which is the difference between the highest frequency and the lowest frequency. It generally depicts a certain range of frequency. It also depicts signal to noise ratio which elaborates on how precisely it is capable of measuring a signal relative to the amount of noise introduced by the system. Fig. 3. ADC 0809 chip [4] The original bandwidth of an ADC is identified initially by its sampling rate, and to a lesser extent by the way it handles errors such as aliasing. The dynamic range of an ADC is affected by a number of factors, including the resolution which implies the number of output levels it can regulate a signal to, linearity and accuracy which implies how efficiently the quantization levels match the actual analog signal and jitter which refers to minimal timing errors that introduce additional disturbance to the signal which is generally referred to as noise. The dynamic range of an ADC is often explained in terms of its effective number (ENOB), the number of bits of each measure it returns that are on average not noise. An ideal ADC has an ENOB similar to its resolution. ADCs are chosen to match the bandwidth and required signal to noise ratio of the signal to be quantized. If an ADC operates at a sampling rate greater than twice the bandwidth of the signal, then perfect reconstruction is possible given an ideal ADC and neglecting quantization error. The presence of quantization error limits the dynamic range of even an ideal ADC, however, if the dynamic range of the ADC exceeds that of the input signal, its effects may be neglected resulting in an essentially perfect digital representation of the input signal. C. X-Bee transmitter & receiver The X-Bee transmitter and receiver is used in the module of Wireless Sensor Network. The X-Bee is utilized in transferring the normalized intensity level to the other vehicle. The X-Bee is used for faster transfer of data or signal to the other receiver incorporated in the system of the other vehicle. X-Bee transmitter receiver pair consists of Atmel microcontroller It is comparatively much faster and efficient as compared to the ZigBee. In terms of, range and line of sight the ZigBee is inferior to the X-Bee. Due to all these factors, for wireless transmission of signal transmission between the systems the X-Bee was considered to be a better option as compared to the ZigBee transmitter and receiver.

4 Fig 4. X-Bee System[12] The X-bee can send or transfer signal or data within the range of 100 m or 300 ft and has a line of sight of 1.6 kms. The System needs to be incorporated in both the systems. The X- Bee transmitter and receiver has to be incorporated in both the vehicle system for proper functioning of the system. D. Pulse Width Modulator The pulse width modulator performs the main function of regulating the headlight intensity with respect to the threshold headlight specified to the microcontroller. Pulse-width modulation (PWM), as it applies to motor control, is a way of delivering energy through a succession of pulses rather than a continuously varying (analog) signal. By increasing or decreasing pulse width, the controller regulates energy flow to the motor shaft. The motors own inductance acts like a filter, storing energy during the on cycle while releasing it at a rate corresponding to the input or reference signal. In other words, energy flows into the load not so much the switching frequency, but at the reference frequency. PWM is somewhat like pushing a playground-style merry-go-round. The energy of each push is stored in the inertia of the heavy platform, which accelerates gradually with harder, more frequent, or longer-lasting pushes. The riders receive the kinetic energy ina very different manner than it is applied. E.Threshold Intensity A variety of headlights are used in different vehicles, which means the threshold intensity also varies accordingly. Thethreshold intensity is denoted by ( i th ). The threshold intensity is the maximum value which is perceivable to human eyes. It is an elemental component of the proposed system which tackles the problem of temporary blindness. The following flowchart shows the working of microcontroller in dependence with the threshold intensity. Fig. 5.Working of a Microcontroller The flowchart displayed here in Fig. 5 is descriptive about the working of the microcontroller. After reading the intensity of the headlight the microcontroller checks or rather compares the value of the threshold intensity. If it is found to be greater than the threshold then the event is set. Then according to the functioning of the system, it would reduce the intensity value and simultaneously send it to the PWM to modulate the intensity of the headlight.

5 F. Architecture IV. OUTCOME With the help of the proposed system it is expected that the prominent problem of temporary blindness would be curbed. In this paper presentation we have tried to propose a system which would prove to be a cost effective as well as a high performance system which would be affordable and can be easily implemented as well as prove to be an effective solution which would inturn reduce the number of accidents due to excessive exposure of headlight intensity. The proposed system deals with the various problems related to night blindness, but further studies have to be done to deal with the effects of streetlights, climatic changes, etc. which causes problems while driving vehicles at night. REFERENCES Fig. 6. Architecture of the HIC-WSN As shown in Fig. 6, the architecture consist of LDR (light dependent resistor which senses the intensity of headlight of the oncoming vehicle. This intensity is received in analog form. This is converted into digital form with the help of ADC (analog to digital convertor). This value is passed to IC8051 microcontroller which compares the received value with the predefined threshold intensity. If the intensity is greater than the threshold then the signal is passed to the oncoming vehicles system with the help of X -Bee transmitter and receiver system. If the received intensity is less than the threshold value then the event does not occur. In the oncoming vehicles side the signal is received. If the intensity is more than the threshold then the oncoming vehicles microcontroller gives a signal to lower its own intensity. This is done with the help of PWM (Pulse width modulator) which modulates the light to the intensity specified by the microcontroller E. Experimental Setup [1] Victor Nutt, Shubhalaxmi Kher, Headlight Intensity Controller using Wireless Sensor Networks Special Issue of International Journal of Computer Applications( ) on Issues and Challenges in Networking, Intelligence and Computing Technologies ICNICT 2012, November 2012 [2] P. F. Alcantarilla, L. M. Bergasa, P. Jiménez, I. Parra, D. F. Llorca, M. A. Sotelo, S. S. Mayoral Automatic light beam Controller for driver assistance March [3] Niraimathi.S, M.Arthanari, M.Sivakumar, A Fuzzy Approach to Prevent Headlight Glare, International Journal of Computer Science and Information Security (IJCSIS), Vol. 9, No.2,February [4] Chen, Y.L., Night time vehicle light detection on a moving vehicle using image segmentation and analysis techniques WSEAS Trans. Comput. 8(3), (2009). [5] Roumen Petkov, Interactive headlight control system, US patent publication number 2006/ A1, July 13, [6] Shubhalaxmi Kher, Preeti Bajaj., A novel Fuzzy Control of Headlight Intensity for night driving, IEEE, IVS-2000 conference, Dearborn, MI, Sep [7] Joseph S. Stam et al., Continuously variable headlamp control, US Patent number , issue date, Apr 11, [8] Bajaj, P., and Kher, S., Smart Control of Headlight Intensity of Automobiles for Improved Night Vision, 38th SICE Annual Conference, vol. A247, pp , July [9] Kher, S. Bajaj, P., Fuzzy control of head-light intensity of automobiles: design approach, 37th SICE international conference pp , July Fig. 7. Experimental Setup.[1] The proposed system would be setup near the headlights of the vehicle. The system is supposed to be incorporated in both the vehicles for proper working of the system. The system would automatically reduce the intensity of the headlight of the oncoming vehicle using wireless sensor network thus reducing the condition of temporary blindness caused due to excessive exposure to headlights.