Development of path estimation algorithm with laser radar data

Abstracts / JSAE Review Vehicle specifications and experimental data are also prepared in a database for quick reference. With this method, we were able to study torsional vibration level speedily and accurately in the planning and in the preliminary design stage. 9539554 A Study on Low-frequency Brake Squeal Noise Tsuyoshi Kurahachi, Makoto Asai, Jchiro Kido (Toyota Motor Corporation) High-frequency brake squeal (.5-15kHz) often occured in the past. However, low-frequency brake squeal (I-3kHz) also occurs, and eliminating this type of squeal has become an important task. In this study, we assumed that the low-frequency squeal is self-exited vibration caused by fluctuations in the friction between brake disc rotor and pad contact surface, and investigated characteristics of the phenomenon by complex eigenvalue analysis using a simplified three-degrceof-freedom system model. Finally, we analyzed the low-frequency squeal by complex eigenvalue analysis using FEM model of the entire brake system, and confirmed the usefulness of this method by experimental validation. 9539563 A Portable Acoustic Measurement System in a Vehicle Yasuhiro Fuse, Satoru Tazaki (Clarion Co. Ltd.) Cabin We are now researching relationships between the physical characteristics and human psychological characteristics in acoustics in a car. For this purpose, we developed an acoustics measurement system composed of two parts. One is a portable audio analyzer which calculates and displays the physical characteristics at various modes, and the other is the Microphone Moving System which measures the sound pressure level inside the vehicle cabin. 9539572 Estimation of Vibration and Acoustic Response in a Tractor Cabin Using Statistical Energy Analysis Kunio Dan (Doshisha University Graduate School), Takayuki Koizumi, Nobutaka Tsujiuchi (Doshisha University), lsamu Kubomoto, Eiichi Jshida (Kubota Corporation) The purpose of this paper is to predict vibration response of the parts in a tractor cabin in engine-idling status using Statistical Energy Analysis (SEA). First, modal density and loss factor of each part is estimated, and it was found that modal density of plane parts is constant regardless of frequency, while that of complex parts changes with frequency. Then, vibration response was calculated using these parameters. Comparing calculational data with experimental data, it was shown that the error between them decreases as mode number per frequency band increases. It also becomes evident that an application limit exists in SEA. 9539581 Reduction of Vibration and Noise of Tractor Cabin using Active Mass Damper Hiroshi Adachi (Doshisha University Graduate School), Takayuki Koizumi, Nobutaka Tsujiuchi (Doshisha University), Jsamu Kubomoto, Eiichi Jshida (Kubota Corporation) The purpose of this paper is to reduce vibration and noise in the tractor cabin using a mass damper actuator. First, in the tractor cabin, vibration and noise are measured and the contribution ratio of solid born noise, that can be decreased, is investigated. Next the control effectiveness of the active mass damper is understood, and the active control system is designed based on velocity feedback control theory. Applying this control system to the tractor cabin, the vibration and noise can be decreased. 9539590 Control of Car Parking Using Neural Network Yoshihiro Adachi (Zexel R&D Center) This paper presents the control of car parking by using the Neural Network technology. A simplified model with two wheels is used to represent a vehicle. A matrix is constructed to express the positions of obstacles with respect to the vehicle. The input vector for the Neural Network is computed from the matrix, and the output vector consists of the steering angle and the direction (i.e. forward or backward) of motion. The back propagation learning rule is used to train the controller.

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Computer simulations of this controller dealing with car parking problems.

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have proved highly efficient

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9539608 Development of Steering Control Algorithm using Visual Information Ken’ichi Yoshimoto (The University of Tokyo), Hideki Ogawa (Tokyo Marine), Hiroshi Kubota (The University of Tokyo Graduate School) An automatic steering control algorithm was proposed, which used motion of objects in a visual image (Optical Flow) obtained from an JTV camera looking ahead in the situation without forward vehicles. This algorithm is improved to apply to the situation in which the forward tracking course is made invisible by the interference of forward vehicles. The adjustment of the control parameters against the change of vehicle speed is confirmed by computer simulation experiments. Development of Path Estimation Algorithm with Laser Radar Data Yasunori Yamamoto, Ayumu Doi, Tohru Yoshioka, Tomohiko Adachi (Mazda Motor Corporation) We have been developing the technology of headway-distance measurement to improve vehicle safety from the viewpoint of “Collision Avoidance.” Its two key elements are obstacle detection with a scanning laser radar (SLR) and path estimation. The obstacle detection is to understand the location of other vehicles or obstacles, and the path estimation is to determine the preceding vehicle. We developed a new algorithm for path estimation which does not require expensive CCD cameras and yaw rate sensors. The effective estimation is achieved by observing longitudinal and lateral movement of obstacles with SLR. This paper describes its basic idea, formulation and experiment results. 9539626 Development of Intelligent IC Voltage Regulator Katsuji Marumoto, Atsushi Kannke, Keiichi Mashino (Hitachi, Ltd.) An intelligent JC regulator was developed to improve the efficiency of automotive alternators. The JC regulator controls the output voltage by Pulse Width Modulation and the driving torque by field current detection. It also incorporates diagnosis and warning functions to indicate system malfunction. 9539635 60GHz Mixer MMIC for Millimeter Wave Radar Yoshiki Ueno, Takashi Taguchi, Kunihiko Sasaki, Tadashi Hattori (Nippondenso Co., Ltd.) Monolithic Microwave Integrated Circuits (MMJCS) are key components of millimeter wave radars for automotive collision avoidance systems: We developed a 60 GHz low loss mixer MMlC for this application by using a new device and circuit simulation techniques. To decrease the modulation noise that is peculiar to an FMCW (Frequency Modulated Continuous Wave) system, we introduced a phase shift circuit that compensates the frequency responses of mixer diodes. 9539644 Inertial Unit for Detection of Acceleration and Angular Acceleration Jun Mizuno, Kay Nottmeyer, Takashi Kobayashi @exe1 Corporation), Kazuyuki Minami, Masayoshi Esashi (Tohoku University) In recent years there has been a growing demand for acceleration sensors for applications in automobiles and in robotics. A silicon micromachined structure. Icm X 2cm in size was designed and fabricated, which can detect not only translational acceleration but also angular acceleration at the same time. This is achieved by capacitive detection of the respective displacement and tilt of a seismic mass, which is symmetrically suspended with torsion bars. The ratio of the sensitivities to translational acceleration and angular acceleration can be influenced by proper choice of the dimensions and the shape of the torsion bars. 9539653 Development of Heart Rate Sensor for Automobiles Atsushi Nakashima, Kazutoshi Ebe, Hazime Jnagaki (Toyota Central Research & Development Labs., Inc.) An ambulatory monitoring sensor of driver’s heart rates has been developed. The sensor is a wrist band type which can be worn easily. The