Autonomous Vehicles - KPIT

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Figure 2: 3-D view of a terrain recreated using Aerial LIDAR [5] IV. Radar The principal of Radar is similar to that of LIDAR except that it uses other part of electromagnetic spectrum i.e., Radio waves and uses frequency change in the reflected wave caused by Doppler effect (see Fig. 3). It can be used to determine position of the object. The radar can be used effectively for long range characteristics – ranges at which other electromagnetic wavelengths are strongly attenuated. For example, it can be used in adaptive cruise control to detect obstacles up to 200 m in front of the car. The disadvantage with Radar is that scattering effect of radio waves highly depends on the size, shape and material of the target. Smaller objects reflect the original wave in similar frequency results in inability to identify position of the object. Similarly, objects made up of radar absorbing material and magnetic substances, sometimes, hinder the efficiency of radar in finding position of the object. The ability of radar to sense the range, altitude, direction or speed of objects helps the unmanned vehicle to visualise the real scene and drive safely. Radars are available in market at different ranges around $30 USD to $300 USD depending upon the accuracy and additional features [13]. V. Ultrasonic sensor Unmanned vehicles using ultrasonic sensors navigate similar to Bats by using ultrasound with frequency greater than that of human hearing range. The principal is similar to Radar but can be used to provide proximity for low speed events i.e., the sensors are blind if cars move fast. This kind of sensors can be used for APS, low-speed ACC and automatic door opener (opens the door when sensor detects a person coming towards it). Although ultrasonic-sensor technology is more mature and less expensive than radar, car manufacturers are reluctant to have too many ultrasound sensor apertures visible on the car's exterior. At present, Ultrasonic sensors are used in conventional cars for assisting reverse parking and the whole system cost is around $70 USD [9]. Figure 3: Doppler Effect – The frequency of radio wave increases when object approaches towards receiver and increases when moves away [6] VI. Infrared Sensor Most of the objects near room temperature emit thermal radiation which corresponds to electromagnetic radiation of longer wavelength. These radiations are not visible to normal human eye and hence this sensor in autonomous vehicles helps to avoid distraction of neighboring drivers with visible light. Unlike radar, LIDAR and ultrasonic, long wavelength infrared called as Far Infra-Red (FIR) sensor doesn't radiate or generate any energy for detection purpose. Instead, it detects infrared radiation from an object. But, Near Infra-Red (NIR) sensors require infrared headlights over the car to illuminate the road ahead. The detection is possible even in the night time and hence used in unmanned vehicles to provide night vision (see Fig. 4) for smart driving. Infrared camera for automobile costs around $150 USD [11]. Thermal cameras use infrared sensors. 24 TechTalk@KPIT, Volume 6, Issue 4, 2013
Figure 4: Infrared image of a street showing various temperature fields [7] VII. GPS Navigation device GPS is a satellite based navigation system helps to find the position and information regarding locations anywhere on the earth where there is clear line of sight to four or more GPS satellites. This navigation system provides directions and traffic congestion maps to autonomous car for deciding the best route to travel in short time. This also helps to keep track of your robotic car, finding the best place to park and also helps to find the speed of travel in real time. GPS Navigation systems are available from $60 to $250 USD [10]. VIII. Carputer The above mentioned sensors cannot be called as “Smart sensors” without interfacing them with embedded system or computers. Autonomous vehicles produce lot of data and require real time processing to make travel safe. This requires additional processing capability of the computer to be used with the sensors. Specially designed mobile computers with high processing capability to be used in robotic cars can be categorised under Carputer. The carputer also provides touch screen interfaces to get inputs for the autonomous cars from the passengers and also for displaying information regarding the travels. IX. Conclusion The principal of all described sensors might seem simple but in unmanned vehicles they are used smartly to provide a flawless autonomous system. Among the briefed sensors, optical cameras and Infrared c a m e r a s h a v e b e e n e x t e n s i v e l y experimented on autonomous vehicles because of their low cost, size and versatility. LIDAR and Radar have also been experimented by some companies that give more importance to reliability than aesthetic of the car. Even though ultrasonic sensors provide reliable measurements; they have been utilised only for small modules in the unmanned vehicles. Presently, the advantage of each sensor are added by making a hybrid system of different sensors to cross check the measurement of individual sensors. This hybrid system helps the robotic cars to provide hassle-free travel. In the future, the robotic cars would be designed in such a way that it can interact with fellow vehicles and help to make prior decision against the future movement of neighboring cars. This kind of interactive environment between unmanned vehicles would result in reduction of number of accidents. Even though, autonomous cars are years far for commercial use, we believe that they can transform society as profoundly as the Internet and mobile phones have. References [1] http://en.wikipedia.org/wiki/Google_driverless_car [2] http://en.wikipedia.org/wiki/Autonomous_car [3] http://flickr.com/ [4] D. B. Gennery, “A Stereo Vision System for an Autonomous Vehicle”, International Joint Conference on Artificial Intelligence, 1977. [5] http://www.groupeinfoconsult.com/lidar [6] http://www.vebidoo.de/ [7] http://www.gizmag.com/ [8] T. Deyle, “Velodyne HDL-64E Laser Rangefinder (LIDAR) Pseudo Disassemble”, 2009. Available: http://www.hizook.com/ [9] http://shopping.rediff.com/ [10] http://www.snapdeal.com/ [11] C. Vieider et al., “Low-cost far infrared bolometer camera for automotive use”, Proceeding of international society for optics and photonics, 2010. [12] http://www.citizensinspace.org/2012/11/low-cost-high-speedimaging-options/ [13] http://www.amazon.com/ [14] http://www.indianexpress.com/news/chinese-military-testsunmanned-smart-car/1064353/ TechTalk@KPIT, Volume 6, Issue 4, 2013 525
Page 1 and 2: TechTalk@KPIT a quarterly journal o
Page 3 and 4: Contents Editorial Guest Editorial
Page 5 and 6: Dr. Vinay G. Vaidya CTO KPIT Techno
Page 7 and 8: Journey Without Driver About the Au
Page 9 and 10: A. Stanford Cart - The First Smart
Page 11 and 12: autonomous vehicles in 2004. The Gr
Page 13 and 14: obtained by laser range finder. The
Page 15 and 16: To Be or Not To Be... A Driver Abou
Page 17 and 18: When the autonomous vehicle complet
Page 19 and 20: ultrasonic sensors, etc. provide vi
Page 21 and 22: Scientist Profile Sebastian Thrun S
Page 23 and 24: Seeing Through Sensors About the Au
Page 25: Figure 1: A robotic Volkswagen Pass
Page 29 and 30: Bringing Vision to Life About the A
Page 31 and 32: Radar needs an attention, there exi
Page 33 and 34: Sr. No. Table 1: List of patents fi
Page 35 and 36: Drive-By-Wire : A KPIT Case Study A
Page 37 and 38: the operational accuracy, it is har
Page 39 and 40: DRIVERS BRAKE HYDRAULIC MOTOR Manua
Page 41 and 42: Wired Through Wireless About the Au
Page 43 and 44: FORWARD OBSTACLE DETECTION AND AVOI
Page 45 and 46: Microcontroller Abstraction Layer (
Page 47 and 48: Autonomous Intelligent Vehicles Aut
Page 49 and 50: Inside Connected Vehicle About the
Page 51 and 52: D. Communications security (COMSEC)
Page 53 and 54: security built-in from the very beg
Page 55 and 56: Gazing Through a Crystal Ball About
Page 57 and 58: Thus, from a passenger acceptance a
Page 59 and 60: About KPIT Technologies Limited KPI

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