Design & Implementation of CAN Bus for Intelligent Vehicle using Sensors System

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1 IJIRST International Journal for Innovative Research in Science & Technology Volume 2 Issue 11 April 2016 ISSN (online): Design & Implementation of CAN Bus for Intelligent Vehicle using Sensors System Kamal Indurkar Savita S. Pathade Trushna S. Kale Kirti Chokhandre Prof. Rahul Hiware Abstract The main purpose of this project is to develop CAN BUS for intelligent vehicles system. This can contribute to construct safer vehicles, improving the treatment for crash victims, and enhancing road status in order to decrease the death rate. In this project we are using CAN BUS. CAN is a multicast-based communication protocol characterized by the deterministic resolution of the contention, low cost and simple implementation. ABS is implemented in the project for preventing the vehicle from the accident using ultrasonic sensor and MEMS technology is used to detect the tilt and vibration level of the vehicle Keywords: Vehicle, Microcontroller, Sensors, CAN, Ultrasonic, Accelerometer I. INTRODUCTION According to the World Health Organization, more than a million people in the world die each year because of accidents [1]. Controller Area Network (CAN) is a serial network that was originally designed for the automotive industry, but has also become a popular bus in industrial automation as well as other applications [2]. The CAN bus is primarily used in embedded systems, and as its name implies, is the network established among microcontrollers [3]. It is a two-wire, half duplex, high-speed network system and is well suited for high speed applications using short messages [4]. Its robustness, reliability and the large following from the semiconductor industry are some of the benefits with CAN [5]. In order to implement this project we are using the following sensors, the project is just a prototype so 1-2 sensors we are using over here [6]. This involves the design and development of the fixture to unload the control valve from assembly line solely with the objective of safety of the worker and to reduce the human fatigue. This model is all about designing and development of fixture carrying valve assembly. On completion of this model anyone may gain the enough knowledge about design, mechanism, fabrication and pneumatics. How do CAN Bus Modules Communicate? CAN bus uses two dedicated wires for communication. The wires are called CAN high and CAN low. When the CAN bus is in idle mode, both lines carry 2.5V. When data bits are being transmitted, the CAN high line goes to 3.75V and the CAN low drops to 1.25V, thereby generating a 2.5V differential between the lines. Since communication relies on a voltage differential between the two buses lines, the CAN bus is NOT sensitive to inductive spikes, electrical fields or other noise. This makes CAN bus a reliable choice for networked communications on mobile equipment. Fig. 1: All rights reserved by 151

2 CAN power can be supplied through CAN bus. Or a power supply for the CAN bus modules can be arranged separately. The power supply wiring can be either totally separate from the CAN bus lines (Using suitable gauge wiring for each module) resulting in two 2-wire cables being utilized for the network, or it can be integrated into the same cable as the CAN bus lines resulting in a single 4-wire cable. CAN bus cabling is available from multiple vendors. The CAN Bus (Controller Area Network) is a vehicle bus standard designed to allow micro-controllers and devices to communicate with each other within a vehicle without a host computer. CAN is a multi-master broadcast serial bus standard for connecting electronic control units (ECUs). Each node is able to send and receive messages, but not simultaneously. A message consists primarily of an ID (identifier), which represents the priority of the message. A CAN message that is transmitted with highest priority will succeed and the node transmitting the lower priority message will sense this and back off and wait. II. BACKGROUND The CAN protocol is defined as the 2 first layers of the ISO-OSI model: - Physical Layer: Data Link Layer: Fig. 2: ISO-OSI Reference model The typical CAN node is made of two parts: a digital section to generate transmission and reception signals (TxD and RxD) and the physical section to generate differential CAN signals (CAN_H and CAN_L). Fig. 3: Communication Model The CAN bus logic is made of 2 logical levels: 1 for recessive level and 0 for dominant level. The recessive level is the default level. In case of multiple nodes on CAN bus, only the node(s) with the dominant level(s) will win. Fig. 4: Logical States All rights reserved by 152

3 CAN Message Receiving: Fig. 5: CAN Message reception process III. DESIGN OF PROPOSED HARDWARE MODEL In order to control all these sensors and their inputs, a digital processor can be used [1]. As prototype micro controller is used to control Transport system [2]. This will allow the control circuit to be realized by a minimum of circuits [3]. The inputs to the microcontroller, which contain information about the accident, are distributed [4]. The inputs to the microcontroller, which contain information about the accident, are the sensors mentioned above are distributed inside the vehicle [5]. The LCD will show the user about the recorded data when the accident has occurred [6]. The main function of the microcontroller program is to take input samples from different ports [7]. These samples are taken from the sensors installed in the vehicle [8]. Fig. 6: Block Diagram of the Hardware SENSOR: IV. HARDWARE REQUIREMENTS A sensor is a technological device that detects / senses a signal, physical condition and chemical compounds and records, indicates, or otherwise responds to it. - Selection of sensor depends on: 1) Variable measured and application All rights reserved by 153

4 2) Dynamic range 3) Cost, size, usage and ease of maintenance Ultrasonic Ranging Module HC - SR04: Features: 1) Ultrasonic ranging module HC - SR04 provides 2cm - 400cm non-contact. 2) Measurement function, the ranging accuracy can reach to 3mm. The modules includes ultrasonic transmitters, receiver and control circuit. The basic principle of work: 1) Using IO trigger for at least 10us high level signal. 2) The Module automatically sends eight 40 khz and detect whether there is a pulse signal back. 3) IF the signal back, through high level, time of high output IO duration is the time from sending ultrasonic to returning. Test distance = (high level time velocity of sound (340M/S) / 2. Fig. 7; Ultrasonic Sensor Accelerometer ADXL335 FEATURES 1) 3-axis sensing 2) Small, low profile package 3) 4 mm 4 mm 1.45 mm LFCSP a) Working of ADXL335: The ADXL335 is a small, thin, low power, complete 3-axis accelerometer with signal conditioned voltage outputs. The product measures acceleration with a minimum full-scale range of ±3 g. It can measure the static acceleration of gravity in tilt-sensing applications, as well as dynamic acceleration resulting from motion, shock, or vibration. Temperature sensor (LM35): Features: 1) Calibrated directly in Celsius (Centigrade) 2) Linear mv/ C scale factor 3) 0.5 C accuracy guarantee (at +25 C) 4) Rated for full 55 to +150 C range 5) It operate on 4 to 30 volts Fig. 8: Acceleromter Sensor Fig. 9: Temperature Sensor All rights reserved by 154

5 a) Working of LM35: 1) It has an output voltage that is proportional to the Celsius temperature. 2) The scale factor is.01v/oc 3) Another important characteristic of the LM35DZ is that it draws only 60 micro amps from its supply and possesses a low selfheating capability. The sensor self- heating causes less than 0.1 oc temperature rises in still air. V. CONCLUSION Real-time, reliability and flexibility, all these characteristics make CAN BUS an indispensable network communication technology applied in automobile network communication field. This article based on the analysis of the CAN bussing technique, designed CAN BUS working nodes based on which designed the SAE application layer design. It also gives the basic software and hardware implementations of CAN BUS network. Finally, tests results show that the hardware circuit of the CAN BUS network communication structure is stable and software design is reasonable, achieved the goal of this design. REFERENCES [1] Fu Liang, Li Wei. The Development and Design on CAN-bus Controller SJAlOOO [J]. Modem Transportation Technology, 2007, (4). [2] Song Qingkun, Wu Lisong. CAN-bus intelligence nods design [J]. Automation Technology and Application. 2008, (27),7. [3] Chen Shaoshuang. The Design and Research on Automobile Network Information Platform Based on CAN-bus [0]. Dissertation for Master Degree Zhejiang University, 2007, 5. [4] Wyczalek F.A. Market mature 1998 hybrid electric vehicles [J]. Aerospace and Electronic Systems Magazine, IEEE.l999, 14(3) : [5] Gao Suling. The Research on Vehicle Information System Based on CAN-bus [0]. Dissertation for Master Degree, Harbin University of Science and Technology, [6] SAE Jl939/21 - CAN Data Link Layer - Issue , Revised [7] LM35 : datashee All rights reserved by 155