CMD: A Multi-Channel Coordination Scheme for Emergency Message Dissemination in IEEE 1609.4

In the IEEE 1609.4 legacy standard for multi-channel communications in vehicular ad hoc networks(VANETs), the control channel (CCH) is dedicated to broadcast safety messages while the service channels (SCH's) are dedicated to transmit infotainment service content. However, the SCH can be used as an alternative to transmit high priority safety messages in the event that they are invoked during the service channel interval (SCHI). This implies that there is a need to transmit safety messages across multiple available utilized channels to ensure that all vehicles receive the safety message. Transmission across multiple SCH's using the legacy IEEE 1609.4 requires multiple channel switching and therefore introduces further end-to-end delays. Given that safety messaging is a life critical application, it is important that optimal end-to-end delay performance is derived in multi-channel VANET scenarios to ensure reliable safety message dissemination. To tackle this challenge, three primary contributions are in this article: first, a channel coordinator selection approach based on the least average separation distance (LAD) to the vehicles that expect to tune to other SCH's and operates during the control channel interval (CCHI) is proposed. Second, a model to determine the optimal time intervals in which CMD operates during the CCHI is proposed. Third, a contention back-off mechanism for safety message transmission during the SCHI is proposed. Computer simulations and mathematical analysis show that CMD performs better than the legacy IEEE 1609.4 and a selected state-of-the-art multi-channel message dissemination schemes in terms of end-to-end delay and packet reception ratio.Comment: 15 pages, 10 figures, 7 table

FLEX-RO: DESIGN, IMPLEMENTATION, AND CONTROL OF SUBASSEMBLIES FOR AN AGRICULTURAL ROBOTIC PLATFORM

Automation technology in agriculture is growing, making agricultural robotics viable. Innovative field usable multi-purpose robotic platforms are needed for the successful progression of agricultural robotics. Furthermore, the field of agricultural robotics would benefit from a robotic platform design allowing for variable height, thus accommodating navigation throughout various crop growth stages. A variable height machine, Flex-Ro was developed to accommodate this feature. Multiple sub-assemblies were designed and implemented for Flex-Ro. An electronic control unit (ECU) enabled engine was used to power Flex-Ro. An embedded application program was developed to control engine speed using proprietary Controller Area Network (CAN) messages in conjunction with J1939 standard messages. It was observed that the maximum standard deviation from the requested set speed was 8.423 rpm. A hydrostatic transmission system was designed and implemented on Flex-Ro. An embedded application program was developed for controlling the pumps and motors of the hydrostatic transmission utilizing proprietary CAN messages. Additionally, the embedded controller operated a Control Cut Off (CCO) that regulated flow to the spring applied motor brakes and the Electronic Displacement Control (EDC) which controls pump flow. Based on the motor speed data collected, it was observed that an increase in deviation occurred as the operational speed increased with a minimum standard deviation of 6.98 rpm at 50 RPM and a maximum standard deviation of 36.13 rpm at 156 RPM. The measured data should be used in developing further higher level control programs. A vertically adjustable frame was developed to allow Flex-Ro to enter crops at various growth stages. A steering system was developed and programmed to allow for steering control through the CAN bus again using proprietary CAN messages. Lastly, a remote control program was developed to allow messages to be created and wirelessly transmitted to Flex-Ro’s CAN bus for teleoperation. Sub-assemblies of Flex-Ro will be further developed for fully autonomous navigation, and performing various field operations. Advisor: Santosh Pitl

FLEX-RO: DESIGN, IMPLEMENTATION, AND CONTROL OF SUBASSEMBLIES FOR AN AGRICULTURAL ROBOTIC PLATFORM

Automation technology in agriculture is growing, making agricultural robotics viable. Innovative field usable multi-purpose robotic platforms are needed for the successful progression of agricultural robotics. Furthermore, the field of agricultural robotics would benefit from a robotic platform design allowing for variable height, thus accommodating navigation throughout various crop growth stages. A variable height machine, Flex-Ro was developed to accommodate this feature. Multiple sub-assemblies were designed and implemented for Flex-Ro. An electronic control unit (ECU) enabled engine was used to power Flex-Ro. An embedded application program was developed to control engine speed using proprietary Controller Area Network (CAN) messages in conjunction with J1939 standard messages. It was observed that the maximum standard deviation from the requested set speed was 8.423 rpm. A hydrostatic transmission system was designed and implemented on Flex-Ro. An embedded application program was developed for controlling the pumps and motors of the hydrostatic transmission utilizing proprietary CAN messages. Additionally, the embedded controller operated a Control Cut Off (CCO) that regulated flow to the spring applied motor brakes and the Electronic Displacement Control (EDC) which controls pump flow. Based on the motor speed data collected, it was observed that an increase in deviation occurred as the operational speed increased with a minimum standard deviation of 6.98 rpm at 50 RPM and a maximum standard deviation of 36.13 rpm at 156 RPM. The measured data should be used in developing further higher level control programs. A vertically adjustable frame was developed to allow Flex-Ro to enter crops at various growth stages. A steering system was developed and programmed to allow for steering control through the CAN bus again using proprietary CAN messages. Lastly, a remote control program was developed to allow messages to be created and wirelessly transmitted to Flex-Ro’s CAN bus for teleoperation. Sub-assemblies of Flex-Ro will be further developed for fully autonomous navigation, and performing various field operations. Advisor: Santosh Pitl

Detecting Anomalies in Controller Area Network for Automobiles

Availability of interfaces such as WI-FI, Bluetooth and Cellular networks, software components to control a vehicle’s functionality, and lack of security mechanisms in the Controller Area Network (CAN) bus protocol make vehicles vulnerable to attacks. In the recent past, researchers used internal and external attacks on automobiles to demonstrate that it is feasible to compromise the vehicle through the transmission of malicious messages on the vehicle’s CAN bus. To defend against such attacks, we propose three detection techniques. First, cross correlating and validating sensor values across multiple sensors can improve the data integrity of CAN bus messages. Second, the order of the messages from a single Electronic Control Unit (ECU) can be used to detect anomalies. CAN messages from the ECU should always be seen in a specific order as they are transmitted one after the other based on the priorities of messages. Fabrication and suspension attacks can be detected using such schemes. Third, a timing based detector is proposed to observe and detect changes in the timing behavior through deterministic and statistical techniques. An anomaly detection is possible after one malicious message if the CAN bus utilization is less than 50% or after at most three malicious messages if the CAN bus utilization is greater than 50% using a deterministic detection technique. The detection of an attack is possible with good accuracy and low false positive rates using a statistical detection technique but at the cost of longer detection latency

Efficient Control Message Dissemination in Dense Wireless Lighting Networks

Modern lighting systems using LED light sources lead to dense lighting installations. The control of such systems using wireless Machine-to-Machine (M2M) where standard LED light sources are replaced by wirelessly controllable LED light sources create new problems which are investigated in this thesis. Current approaches for control message transmission is such networks are based on broadcasting messages among luminaires. However, adequate communication performance - in particular, sufficiently low latency and synchronicity - is difficult to ensure in such networks, in particular, if the network is part of a wireless building management system and carries not only low-latency broadcast messages but also collects data from sensors. In this thesis, the problem of simultaneously controlling dense wireless lighting control networks with a higher number of luminaires is addressed. Extensive computer simulation shows that current state-of-the-art protocols are not suitable for lighting control applications, especially if complex applications are required such as dimming or colour tuning. The novel D³LC-Suite is proposed, which is specially designed for dense wireless lighting control networks. This suite includes three sub-protocols. First, a protocol to organize a network in form of a cluster tree named CIDER. To ensure that intra-cluster messages can be exchanged simultaneously, a weighted colouring algorithm is applied to reduce the inter cluster interference. To disseminate efficiently control messages a protocol is proposed named RLL. The D³LC-Suite is evaluated and validated using different methods. A convergence analysis show that CIDER is able to form a network in a matter of minutes. Simulation results of RLL indicate that this protocol is well suited for dense wireless applications. In extensive experiments, it is shown that the D³LC-Suite advances the current state-of-the-art in several aspects. The suite is able to deliver control messages across multiple hops meeting the requirements of lighting applications. Especially, it provides a deterministic latency, very promising packet loss ratios in low interference environments, and mechanisms for simultaneous message delivery which is important in terms of Quality of Experience (QoE