Haklin Kimm

Integrated Fault Tolerant System for Automotive Bus Networks

In automotive bus networks all the electronic components are interconnected to transmit and receive signals. The number of vehicles equipped with electronic components is increasing rapidly by replacing traditional mechanical and hydraulic systems. Nowadays most cars are functioning properly via many Electronic Control Units (ECUs), sensors and actuators, among which more than 2500 electronic signals are exchanged. There are several bus systems that have been developed for automotive bus systems to satisfy the different requirements of automotive applications: Local Interconnection Network (LIN), Controller Area Network (CAN), FlexRay and Media Oriented System Transport (MOST). However, there are more demands of combining these different bus networks in order to increase the efficiency and safety of the vehicle systems. The integrated automotive bus system, which communicates with software/hardware components on the different bus systems in a car, is more challenging problem. The discussion on how to interconnect those automotive bus networks in a fault tolerant way is addressed in the paper.

Evaluation of interval-based dynamic voltage scaling algorithms on mobile Linux system

During the last several years, dynamic voltage scaling (DVS) algorithms are being used for energy consumption on real, fully functional battery supplied devices, adjusting the clock speed and supply voltage dynamically. Most DVS algorithms are investigated in interval-based and task-based strategies. Task-based algorithms consider task information, especially task deadline, on deciding what speed to choose at any given time. Interval-based algorithms predict the CPU speed of the upcoming interval based on observations of the CPU utilization of previous intervals, and then set the speed for that interval based on this prediction. Most DVS algorithms have only been tested in simulation environments. In this paper, those interval-based DVS algorithms are modified with different parameters on different workloads, and evaluated to know which one saves the most energy while not degrading computer performance.

Edge Detection and Linking Pattern Analysis Using Markov Chains

There have been many studies on developing more accurate edge detection algorithms and employing them for various applications - especially in geographic information system images and maps, say coastline images. In this paper the coastline images are implemented with an edge detection algorithm using the MATLAB programs, and the edge detected images are analyzed so as to reconnect broken links. In doing so Markov transition probability matrices are generated upon the edge images and processed in order to analyze the edge linking patterns of the coastline images. Furthermore, the image analysis using the Markov Chains shall be extended and acknowledged as another alternative that can be a replacement or supportive to traditional coastline mapping techniques, because the Markov Chain represents the pattern of the coastline images numerically.

Controller Area Network for fault tolerant small satellite system design

The Controller Area Network (CAN) is a message based event triggered communication bus mostly used in the automotive industry. In this paper, however, the CAN bus is tested for being applicable to small satellite systems in order to provide better fault-tolerance. The CAN bus connects several independent CAN modules and allows them to communicate and work together asynchronously and/or synchronously. The CAN modules were designed to decrease weight and cost while improving stability and power consumption compared to current small satellite systems. We present advantages to using the CAN bus over existing satellite bus systems, design and propose a CAN protocol for CubeSats.

Failure management development for integrated automotive safety-critical software systems

Nowadays the number of vehicles equipped with electronic components is increasing rapidly by replacing mechanical and hydraulic systems. The most advanced cars function appropriately via more than 50 Electronic Control Units (ECUs), sensors and actuators that exchange more than 2500 electronic signals among them. The electronic components are interconnected with automotive bus systems. There are several bus systems that have been developed or improved in automotive bus systems to meet the different requirements for automotive applications: Local Interconnection Network (LIN), Controller Area Network (CAN), FlexRay and Media Oriented System Transport (MOST). However, there are demands to combine these different bus systems to increase the efficiency and safety of the vehicle systems. Failure management is a most challenging problem in car industry since the integrated automotive system needs to communicate with software/hardware components on the different bus systems in a car. The discussion on how to interconnect those automotive bus systems in a safety-critical way is addressed in the paper, where failure management should be applied.

The overhead model of word-level and page-level incremental checkpointing

Generally, word-level granularity for incremental checkpointing may reduce the checkpoint file size, and hence get better the performance. However, word-level granularity may not always be more efficient than page-level granularity, because word-level granularity may sometimes increase the checkpointing overhead for finding the differences between two checkpoints and for writing the address of the modified word to stable storage. In this paper, we make the overhead model and find factors which produce an effect on the over-head. We also show that the model and the factors are fairly reasonable via experimental results from Linux Kernel-level incremental checkpointing facility.

Payload system development for high altitude balloon

A balloonSat weighs up to around 4 kg and soars up to reach altitudes of 100,000 feet or higher using a high altitude balloon with its diameter of 10 to 12 feet mostly, but costs only several hundred dollars. This altitude of the stratosphere provides harsh conditions of tough and significant scientific and engineering challenges. High-altitude balloons can carry small payloads to altitudes higher than 80,000 feet into the stratosphere, in which part of space the conditions and atmosphere are quite similar to those in low-Earth orbit, so as to call it as near-space. In this balloonSat project, the payload systems are developed based upon a cubic satellite, which is equipped with a 16-bit microcontroller; wireless 2.4 GHz modem that transmits signals well to a receiver on the ground consistently upon various cosmic radiation levels in the near-space; the 9-degree sensor that collects and transmits in real time during the whole flight. In the meantime to track the BalloonSat throughout the whole flight so as to recover it safely, the GPS and Automatic Position Reporting System (APRS) are deployed with the balloonSat.

Multifunction GPS embedded wrist device for runners

In this paper we represent a wearable wrist device for runners that is equipped with a GPS chip and programmable features. While running, the device would offer velocity, distance and time measurements at a glance. A button to begin and end a tagged area would also be available so that runners could mark particular parts of their run over which they wish to improve their time. The primary components of the proposed wrist device are as follows: a Microchip dsPIC 33FJ128MC802, a Sparkfun 128×128 pixel color LCD, and the LS20031 GPS chip, also available through Sparkfun. However, these components will be reviewed again and replaced with more suitable ones later.

Distributed event-triggered robot control system over controller area network

In this paper the distributed control systems, of which components are managed with event-triggered and/or time-triggered approaches to exchange messages and function properly, are discussed. Furthermore a prototype of the distributed control systems is designed, developed and tested so as to understand more and to find a better way to control various components of the real-time systems efficiently. The proposed prototype system is implemented over the controller area network (CAN) to have several components/robots function in synchronous and asynchronous ways. In order to understand the relationship of the hardware/software components of the prototype system, the unified modeling language (UML) diagrams are developed while building the test bed system physically and developing programs to function properly for the components of the proposed system.

Efficient use of java MIDP record management system in wireless devices

We present an approach that can promote the efficient use of the Java Mobile Information Device Profile (MIDP) record management system (RMS) in wireless devices such that faster record retrieval using a smaller memory is achieved, which makes the device consume less battery power. The comparable program segments, which show how to use Java MIDP RMS efficiently with or without a record-enumeration interface, are presented and analyzed. The proposed approach supports faster access of record traversal, which shows O(log n) time to retrieve any record in an MIDP RMS file, while the record retrieval in the current Java MIDP RMS takes O(n) time. In addition, the proposed approach uses less RMS storage than the method using the record-enumeration interface does