Development of new electronic 4WD system

Abstracts /JSAE Review 17 (1996) 435-458 (2) Whether variables of dynamics can be measured, or only geometric variables can be measured. Simulation studies are done for the purpose of evaluation of the algorithms. Simulation results under the condition of constant speed, varying speed and varying distance between the leading car and the following car are discussed. 9633603 Development of Active Controlled Steering System for Active Safety - A Proposal for Avoidance of Collision - Katsutoshi Nishizaki, Shiro Nakano, Yoshihiro Goto, Tomoyasu Kada (Koyo Seiko Co., Ltd.) This paper describes the control strategy of a steering system for avoidance of collision. This system detects driver's handling action and side/rear neighboring vehicles' approach, then controls the action if it is going collide with those vehicles. In order to recognize the driver's intention only from his handling action, we experimented with varied handling patterns in different driving conditions, and analyzed the dynamic characteristics of each steering torque. The test results suggest that this system is effective in reduction of traffic accidents. 9633612 Simulation of Urgent Obstacle Avoidance Using Genetic Algorithm Minoru Onda, Tadahiro Katagiri, Masao Nagai (Tokyo University of Agriculture and Technology) Reduction of traffic accidents has become an increasingly important issue during recent years with the advance of the automobile society. A key to coping with this issue is to investigate thoroughly the behavior of drivers, especially in emergency situations, such as the case of suddenly encountering an obstacle during driving. Assuming an emergency situation of obstacle avoidance, taking consideration of the nonlinearity of tires, this paper studies the characteristics of the driver under the critical condition by way of a genetic algorithm (GA). 9633621 Development of Extended C Language for Vehicle Control Nobuynki Isono, Nobuyasu Suzumura (Aisin Seiki Co., Ltd.), Fr~dtric Craisson, Toshio Okoshi (IMRA Europe S.A.) Electronic controls are indispensable for Automobiles, and more complex functions are demanded year after year. In terms of software development for electric control units, the rate of developing time of programs is increasing, so a high-level language, suitable for vehicle control, becomes necessary. In this context, we have defined an extension of the C language, suitable for vehicle control, and built up the associated pre-processor. 9633630 Braking Device using Fluid Friction by Applying an Electric Field Kunio Shimada (Toyama University), Toyohisa Fujita (Akita University), Makio lwabuchi, Kenichi Okui (Toyama University) Basic research on a braking device which uses rotating actuators controlled by applying an electric field were made experimentally and theoretically. This device has an electrotheological fluid (ER fluid) type of particle dispersion which is elastic in a solvent. By supplying a D.C. voltage to the ER fluid, its viscosity is increased and the rotating disk can be stopped. The torque and number of revolutions were measured. The experimental data were compared with the theoretical analysis, taking into account the elasticity of the particles. 9633649 Development of New Electronic 4WD System Tomoynki Hara, Kouji Nishio (Nissan Motor Co., Ltd.) Sport-utility vehicles are required to have a very high level of both on-road and off-road performance. Nissan Motor Company has recently developed a new electronic torque split four-wheel drive system by which these high levels of performance can be achieved. This paper describes the development aims of the new system, its construction and technological features, the details of its driving power distribution control mechanism and the performance obtained in actual vehicle tests.

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9633658 Torque Distribution Management in a New Electronic 4WD System Toshiharu Takasaki, Kazuyuki Kono, Akira Kikuchi (Nissan Motor Co., Ltd.) This paper describes a new electronic torque split 4WD system that provides good driving performance under both on- and off-road conditions. It automatically distributes the optimum level of torque to the front wheels according to the road conditions and vehicle operating conditions. This optimized management of torque distribution achieves consistently high levels of driving performance. 9633667 Theoretical and Experimental Analysis of On-Center Stability of Large Size Vehicles - The 2rid Report: On-Center Stability of Tandem-Rear-Axle Tracks - Fujio Momiyama, Hirokazu Okuyama, Akira Takeishi (Hino Motors, Ltd.), Katsumi Kageyama (Emeritus Professor of Nihon University) A principle of on-center stability characteristics was hypothesized and verified by numerical analyses and experiments. There is an inflection speed point (ISP) at which the vehicle behavior and driving security feel change. The existence of ISP is caused by slight lateral and directional movement of unsprung masses. The location of the instance movement center is the key to on-center stability design. 9633676 Stability Analysis of Articulated Vehicles with All-WheelSteering Sunao Chikamori, Yutaka Shimizu (Seikei University), Kawasawa Shouzou (Mitsubishi Motors Co.) We introduce the state equations of the articulated vehicles with all-wheel-steering, and built a servo control system to make each vehicle follow its individual target. By applying the feedback regulator, all wheels become able to steer optimally. In the case of pulling I ~ 3 semi-trailer units, we conducted a series of simulations on typical transient maneuvers. The results of these simulations indicate that the allwheel-steering of articulated vehicles is highly effective for improving directional stability. 9633685 Modeling of Shimmy Phenomenon on Steering System of Large Size Vehicle Toshiki Ezoe, Ichiro Kageyama (Nihon University), Fujio Momiyama, Kiyoaki Miyazaki (Hino Motors, Ltd.) Shimmy is "known as a vibration of the steering system of vehicles. When a large size vehicle goes over a protuberance, the shimmy appears at around 60 k m / h , and does not disappear at around this speed. This phenomenon has not yet been understood. This paper discribes the shimmy phenomenon using an analysis of a steering system model of large size vehicle with the tire model for dynamics of lateral force proposed by the authors. It was found that this model gives a good description of the shimmy phenomenon. We consider the influence of Coulomb friction around the steering axis on the shimmy phenomenon, and it is shown that this theoretical model expresses the shimmy phenomenon qualitatively. Finally, using a full vehicle model, the shimmy phenomenon is quantitatively described. 9633694 A Study on Lane Change Maneuver of Tracked Vehicles Numerical Simulation Employing a Linear Preview Model - Kouetsu Takano, Keiji Watanabe, Masanori Kitano, Hiroshi Harada (The National Defense Academy) A mathematical model was developed for tracked vehicles which predicts the response of the vehicle-driver as a closed loop system. The model is based upon available nonlinear equations of motion and the linear preview model. To evaluate the effect of vehicle speed, adhesion of track-ground contact area and driver position on the preview time and the steering gain, a numerical simulation of lane change motion was conducted. The results demonstrate that the proposed model is a useful design aid for achieving optimum performance at high speeds. 9633702 Development of a Car Navigation System with a Bird's-eye View Map Display Norimasa Kishi, Masaki Watanabe, Okihiko Nakayama (Nissan Motor Co., Ltd.)