Department Publications

We present a simulation study of a cooperate car following application implemented by the Wireless Access for Vehicular Environments (WAVE) protocol stack, which uses the MAC and Physical layers defined by the IEEE 802.11p protocol. This is a simple Intelligent Transportation Systems (ITS) application which forms the foundation for autonomous driving. As with many safety-critical ITS applications, cooperate car following uses beaconing as the primary means of communication. The beacon frequency and the transmit power of the mobile nodes are considered as the key communication parameters, while the vehicle density is considered as the key traffic parameter. The two main factors affecting the performance, the end-to-end delay and the packet loss, are studied for different scenarios defined by the above parameters. Results indicate how the application performance may be improved by adapting the …

Vehicular ad-hoc networks (VANETs) play a vital role in enabling intelligent transport services (ITS). The state of art dedicated short range communication (DSRC), which is envisioned to facilitate the communication in VANETs, requires dedicated hardware. This hinders the penetration of ITS especially in developing countries. This paper studies the suitability of Wi-Fi Direct (WD), which is readily available on many smart phones, as an alternative communication technology for VANETs. Performance measures such as throughput, end-to-end delay, packet receiving/loss ratios for both WD and DSRC are presented through simulations, using network simulator NS3, and the traffic simulator Simulation of Urban Mobility (SUMO). Both single-hop and multi-hop communication is considered. The results show the potential of WD as an alternative communication technology for VANETs.

Vehicle tracking and surveillance is an area which is having a considerable attention in the context of security and safety. The detection and tacking of moving vehicles through multiple cameras is considered as a method of vehicle surveillance. This work addresses a problem of detecting and matching vehicles through multiple cameras. The power of GPUs are used to increase the number of video streams which can be processed using a single computer. In the detection process the Gabor filter is used as a directional filter and the SURF is used by the matcher to uniquely represent the vehicle.

An informative digital map is a prerequisite for future Intelligent Transportation System (ITS) applications such as lane level navigation systems. Preparing and updating such detailed digital maps by using existing methods such as surveying and image digitization is not practical due to the time and cost involved. We propose a method that statistically mines Global Positioning System (GPS) trajectory data obtained from vehicles to generate a lane level digital map of the road. The proposed method is capable of generating a digital map of the road which contains lane centerlines. The proposed method is independent of the lane width, lane parallelism and can handle lane splits and merges. In addition, a method that can be used to generate a map of lane boundaries is also presented. The proposed methods have been tested using the GPS data collected using vehicles equipped with GPS enabled mobile phones …

Typical Automatic Number Plate Recognition (ANPR) system uses high resolution cameras to acquire good quality images of the vehicles passing through. In these images, license plates are localized, characters are segmented, and recognized to determine the identity of the vehicles. However, the steps in this workflow will fail to produce expected results in low resolution images and in a less constrained environment. Thus in this work, several improvements are made to this ANPR workflow by incorporating intelligent heuristics, image processing techniques and domain knowledge to build an ANPR system that is capable of identifying vehicles even in low resolution video frames. Main advantages of our system are that it is able to operate in real-time, does not rely on special hardware, and not constrained by environmental conditions. Low quality surveillance video data acquired from a toll system is used to …

We present a novel method where smart phone sensors are used to sense the prevailing traffic situation and to share extracted information among a community. Instead of using the power-hungry GPS receiver in the mobile device for detecting congestion through vehicular motion, we use the accelerometer along with a novel algorithm. We show that traffic congestion situations can be identified with 78% accuracy with our technique. Vehicular traffic has become a severe problem, particularly in the less developed countries. Therefore pre awareness of congestion situations is very important for an efficient lifestyle.

It is known that every working day millions of drivers are looking for a place to park and most of the urban traffic occur due to the drivers loitering in search of parking spaces. We wished to offer a simple solution to this problem by implementing a car park navigating system using ultrasonic sensors. RS-485 protocol, a mobile application and Bluetooth communication. The system indicates whether the car park is full or not and provide a simple navigation to the driver to the vacant spot.

In this work we focus on the problem of detecting vehicles that come to a stop, in a video of approximately 15 frames per second. The videos are retrieved by surveillance cameras fixed as shown in Fig. 1 which are located few meters from the ground.

This paper suggests a decision support system for vehicle drivers, accessible via mobile phone. Concept behind the system is to help drivers to schedule their activities, best utilizing their time along the way, minimizing the impacts of traffic. This is in contrast to existing approaches focused on controlling traffic in highways. Vehicle is continuously tracked along the journey and information presented to user is adapted according his location and time dimensions. System is based on a decision tree based classification model to predict the future traffic and use those results for decision making. System mines spatio-temporal data to build the decision tree, therefore developed in a distributed architecture to avoid load for a single server. System is exposed to community via existing social networks, bringing social networks into vehicular context. Decision trees to predict traffic are periodically rebuilt using most recent data …

As the problem of urban traffic congestion spreads, there is a pressing need for the introduction of advanced technology and equipment to improve the state of the art of traffic control. In this context, the techniques used for sensing traffic flow information plays a vital role, ensuring accurate real time controllability. Closed Circuit Television (CCTV) has gained popularity because of its ability to provide diverse information on relatively large regions leading to opportunities for performing substantially more complex tasks than conventional detection schemes. By processing these video images, traffic parameters such as speed, traffic composition, queue length etc. can be extracted. In addition CCTV images can be further processed for other useful information such as detection of vehicle shapes, vehicle types, occurrence of traffic violations and vehicle identification numbers etc. To introduce CCTV based vehicle …

Autonomous personal vehicle systems face many challenges due to complex and unpredictable environments. Thus, much of such platforms' computational resources are wasted on trying to localize in a given environment, slowing down the navigation phase. To overcome this problem we propose intelligent assistance, a novel scheme to assist autonomous mobile platforms by providing localization information externally. In the proposed scheme, the moving targets are detected using a laser range finder and camera based sensor unit and tracked using particle filter based technique. Calculated localization is fed back to the mobile platform as assistance information. The preliminary experiments show the validity of the proposed scheme for mobile robots.

This paper proposes a novel method for a dynamic ridesharing mechanism using the combination of several modern information and communication technologies.

The determination of the motor and battery specification is one of the major challenges in the electric vehicle designs, specially considering the different kinds of requirements and specifications in different designs. This paper discusses about a method of simulating a vehicle in given terrains and driver models for extracting the torque, power and battery usage; and hence get the most optimized set of parameters for the given design requirement. The simulation takes the driver as a fuzzy model and the overall vehicle as a non-linear model for calculating the motor and battery requirements according to the terrain, driver commands and traffic condition.

The paper presents the combined application of Geographical Information Systems (GIS), the Global Positioning System (GPS), the General Packet Radio Service (GPRS) and the Internet for tracking of vehicle fleets. It is one component of an enterprise solution that is designed to manage and track a large fleet. The key features of the system are an open-source GIS platform, real-time location information update, and a web-based user interface. The system consists of GPS-based vehicle tracking devices, a communications server, a web-server, a database server, and a map server. The tracking devices mounted in the vehicles collect location information in real-time via the GPS. This information is transferred continuously through GPRS to a central database. The users are able to view the current location of each of the vehicles in the fleet via a web-based application, and thereby manage the fleet. The vehicle positions and other related information are displayed on a digital map, which is made available by a map server.

This paper discusses the design of a centralized control and monitoring system for railway traffic that can be implemented on top of the existing control logic (interlocking system) of Sri Lanka railways. The overall solution comprises of a central server system and databases with redundancy, relay house hardware unit (with embedded Ethernet and a custom communication protocol for microcontrollers) to interface with the relays of the interlocking system, Dispatchers Controlling Interface for remote monitoring and controlling, and a TCP/IP network which interconnects all the above mentioned components of the total system. The current centralized traffic control (CTC) system in Sri Lanka, located at Maradana, was implemented in the year 1985. This has manually operated switch boards, a relay based operation (separate relays for controls and indications) having every switch hardwired to the relays which are …

The paper presents the combined application of Geographical Information Systems (GIS), the Global Positioning System (GPS), the General Packet Radio Service (GPRS) and the Internet for tracking of vehicle fleets. It is one component of an enterprise solution that is designed to manage and track a large fleet. The key features of the system are an open-source GIS platform, real-time location information update, and a web-based user interface. The system consists of GPS-based vehicle tracking devices, a communications server, a web-server, a database server, and a map server. The tracking devices mounted in the vehicles collect location information in real-time via the GPS. This information is transferred continuously through GPRS to a central database. The users are able to view the current location of each of the vehicles in the fleet via a web-based application, and thereby manage the fleet. The vehicle positions and other related information are displayed on a digital map, which is made available by a map server. It is a typical example of how the advantages of ICTs may be leveraged for the efficient and effective management of a company's resources, particularly in the face of skyrocketing fuel costs.

The design and implementation of a low cost bell and light protection system for a railway level crossing is described. This is directly targeted to cater for the un protected level crossings in Sri Lanka. The design is entirely hardware oriented. It detects the presence of a train on the rail track to activate a set of red lights and a bell to warn the road users. To enhance the reli ability of the system, the electrical continuity of the rail track is also monitored.

The concept of vision information has become a key feature in modern vehicular traffic control and Intelligent Vehicle Highway Systems (IVHS)[1]. Vehicle detection by video cameras is one of the most promising new technologies used in implementing advanced traffic control and management systems [2].

Construction of new highways or expansion of existing highways to meet the everincreasing highway traffic is a very expensive and time-consuming task Management of existing highways effectively is considered as a high priority option in Traffic and Highway Engineering. Trafic control by a system of traffic signal lights and variable message signs that can adapt to the changing environment is an essential part of such management scheme The multiprocessor architecture described in this paper maintains near neighbor connectivity and shares information via these near neighbor interconnections for calculation of optimum traffic plans. The near neighbor connectivity simplifies the expansion of the multiprocessor architecture with city developments

Development of the hardware, firmware and control and monitoring software to interface the UNIROAD Traffic Signal Controller (TSC) to Advanced Traffic Control system (ATCS) is described. This system is capable of controlling and monitoring traffic signal controllers over a standard telephone link. It is specially developed at a low cost for third world countries such as Sri Lanka.

The concept of vision information has become a key feature in modern vehicular traffic control and Intelligent Vehicle Highway Systems (IVHS)[1]. Vehicle detection by video cameras is one of the most promising new technologies used in implementing advanced traffic control and management systems [2]. The CCTV Image Grabber discussed in this paper is a low cost design which can capture, store and transmit video information to a remote computer for visual site inspection and extraction of vehicular traffic parameters for adaptive control of road traffic.

The design and implementation of a low cost solid-state lamp driver and failure detector (LD/FD) for incandescent lamps is described. The design is directly targeted for the signal lamp heads in highway traffic signal systems. This is entirely hardware oriented and can be used to replace the relay systems currently used without doing any modification to control signals. The incorporated lamp failure detection circuitry enhances the features of the design by activating a feed back signal to indicate lamp failures. This feature enables us to develop an automated maintenance scheme in a centralized traffic control system such as the emerging Advanced Traffic Control System (ATCS).

The determination of the motor and battery specification is one of the major challenges in the electric vehicle designs, specially considering the different kinds of requirements and specifications in different designs. This paper discusses about a method of simulating a vehicle in given terrains and driver models for extracting the torque, power and battery usage; and hence get the most optimized set of parameters for the given design requirement. The simulation takes the driver as a fuzzy model and the overall vehicle as a non-linear model for calculating the motor and battery requirements according to the terrain, driver commands and traffic condition.