In April 1996, HONDA announced “HONDA EV PLUS” which is Japanese first real electric vehicle designed from the ground up. It is a practical electric vehicle comfortably accommodating four persons, having just enough performance under the various traffic conditions including freeway with electrical and collision safety.

New Racoon, the bicycle with an electric motor assist system, was developed aiming at reasonable price and excellent utility. Light weight, compact and high efficiency power assist drive system has been achieved by adopting an unified motor with the assist drive system, sensing mechanism of running speed on motor spindle, polyacetal driving gear. Furthermore, convenience was enhanced using U-shaped under-bone frame, battery indicator and one-touch charge system of battery.

Honda has developed a compressed natural gas-powered “Civic GX”.

In order to optimize the engine for natural gas, the high compression ratio, VTEC technology and high strength engine components are employed. Engine durability is substantially improved by developing new materials for the valve and valve seat. A sequential multi-point manifold gaseous injection system and the integrated 2-stage pressure regulator provide precise air-fuel control. Coupled with 600 cell dual catalysts bring extremely low emission capabilities. An all composite CNG tank reduces the weight of vehicle and extends the driving range.

A CNG tank and its associated fuel lines are assembled in a rigid frame. This module assembly create the ease of installation and the protection of essential CNG components from a rear end collision.

After fifty years of Japanese motorization progress, now, the days that everyone utilizes cars every day in the home town have come. On the basis of such understanding, it is required anew to produce “best” cars for “everyone” in “every day life town”.

Honda Logo was developed with the view point shown above, that is , to re-evaluate throughtout the performance of vehicle, re-determine target values to “Suitable Performance for Purpose” and make a password “Perfect Fit High Performance”.

The new designs have been applied to the major part of Logo from package to platform to get value for money at high level. The development management also have been reformed radically and applied to this project.

CBR1100XX Super Blackbird was developed and put onto the market from September 1996, with a high engine performance, good handling characteristics which give the motorcycle behavior as a rider's intention, and an excellent comfortability even if during a long distance cruising riding.

To achieve high engine performance, the engine was newly developed to get a high power and an aerodynamic characteristics was enhanced reducing an air resistance. To achieve good handling characteristics, lightening and compactness for each component, and simplifying for each functional part were considered.

A small four-stroke engine capable of multipositional using has been developed. The engine for hand held equipment provides easy maneuverability like two-stroke engines which are dominated in the small engine market.

The developed technologies include the following items.

①360 degree universally inclinable operation by adopting a new lubrication system.

②Light-weight with a thin uni-block cylinder, etc.

③Normal operation at up to 10,000 rpm while combining high output with a wide torque band including low and medium revolution range.

Easy operation and handling as well as better workability compared with the conventional two-stroke engines are achieved. In addition better starting reliability, drastically improved emission, and half-reduction of running costs are also confirmed.

The 3.0 liter V6 engine for the 1997 model “ACURA CL” has been developed as an engine with a minimum weight and size using the VTEC (Variable Valve Timing & Lift Electronic Control System) mechanism, which is known as a technology that achieves both low fuel consumption and high power output. This engine features a 60 degree V-angle and both compactness and lightweight.

This paper describes a features and effects of technologies incorporated in this engine.

The available electronically controlled 4-speed automatic transmission used on the Prelude and Acura CL 3.0 is a new design: more compact, lighter and more efficient than its predecessor. The low-gear hold function of the previous transmission is now incorporated into the new transmission, so the low one-way clutch and low-hold clutch are eliminated. Major features of the new transmission are as follows,

(1) Centrifugal hydraulic cancellation mechanism added to the 1-2 clutch

(2) Direct hydraulic control system by two linear-solenoids

(3) New shift logic hydraulic circuit

We have developed Active Torque Transfer System (hereafter referred to ATTS) for FF car toimprove the turning performance by distributingoptimum driving force to right-hand and left-handfront wheels. This paper describes about the theoryof controlling vehicle behavior by distributingoptimum driving force to right-hand and left-handfront wheels, the principle of driving forcedistribution using overdrive device and multiple discclutch, the overdrive mechanism with Honda originalplanetary gear, the double joint type suspensionwhich makes the most of driving force distributingfunction, the electronic hydraulic control systemmechanism and the control method, and the performance of ATTS onboard car.

This system was introduced in the new Preludeunveiled in the last autumn, and showed new driving sense which is not inherent in the conventional driving systems.

For the "easy and stable brake operation" of light weight motorcycles, Motor Actuated Combined Antilock Brake System (M.A.-C.ABS) having the function of Combined Brake System on rear brake and Antilock Brake System on front and rear brakes was developed.

To make M.A.-C.ABS small and low cost, a single channel actuator is adopted to control front and rear brakes simultaneously, which consist of functional switch rotation motor, electromagnetic brake, double planetary differential gear and etc.

Test rides by "beginner class rider" have proved the relief from tension and the increase of braking force by 20-30 %.

The M.A.-C.ABS was applied successfully on a 50cc motor scooter of domestic market.

For studying the mechanism of charge stratification on a lean-burn engine (1.5L VTEC-E), analysis is made to air flow and fuel spray motion in intake port and cylinder. In particular, study is made to fuel spray into a cylinder and droplet distribution under different injection timings. The results show that: 1) strong vertical air flow around the center of a combustion chamber during the intake stroke, prevents spray dispersion and creates rather concentrated spray formation; 2) some spray induced by valve slope flows along pent roof to reach exhaust valves: 3) spray from the secondary valve is well atomized due to small opening and then strike into a spark plug for dispersion; 4) sauta mean diameter of droplets which are injected during induction stroke decrease less than 5µm during compression stroke; and 5) there be no fuel droplets having its sauta mean diameter of more than 5µm in cylinder when fuel injection made except induction stroke.

A high precision A/F control technology applied modern control theory is essential to decreasing emission for Honda ULEV. Usual Automotive CISC micro computers are not enough for high speed calculation in order to realize high precision A/F control for this purpose.

This paper described outline of the first gasoline engine ULEV system, especially the high precision A/F control by using newly developed 32bit 1chip RISC micro computer and C-programing.

Four forces act in rings for a metal pushing V-belt. These forces are: two kinds of intercepting forces which prevent blocks from going outside of pulleys (one caused by pulley thrust, the other caused by centrifugal force), frictional force acting between the rings and the blocks, and bending force in longitudinal direction.

In the previous paper ^{1)~3), 5)}, distribution of three forces, excluding centrifugal force, were presented at low belt speed. We successfully measured all four different forces including centrifugal force acting continuously at practical operating conditions for layered rings. In this paper, distribution of these four forces acting on the innermost ring is described at steady states.

The improvement of output power and the reduction of the intake and exhaust noise of the engine are the item to be each other disagreed and need a great development period to finding the point of compromise of these. Therefore, we developed the tool as these can be estimated at the same time in the engine laying-out process. In this paper, the point of view, the precision verification of this simulation and application to the development are described.

Road noise is composed of air-borne and solid-borne noise. It is assumed that the ratio of air-borne and solid-borne noise in road noise depends on rough road surfaces. By making this point clear, effective countermeasures for road noise can be proposed. This paper presents the separation methods of air-borne and solid-borne noise. The proposed methods are proved to be effective through several experiments.

Improving sound quality is essential for a vehicle to intense the competitiveness in the market. A sound quality evaluation method to be able to exactly evaluate the sound is required to attain the improvement mentioned above. The conventional evaluation methods almost do not show quantitatively the frequency area and the level which become real problem on the feel of auditory.

The purpose of this paper is to consider a sound quality evaluation method taking account of the human auditory characteristics and to embody the results as a sound quality evaluation system.

This system allows to faithfully reproduce the original sound since a dummy head microphone is used for recording the sound. With computing process using modelized human auditory characteristics, it is also capable of calculating objective evaluation values which is the same measure as the human auditory sense.

This system has been evaluated effective resulting from the experiments of applying to the evaluation of piston slap noise and interior noise during acceleration.

We have developed the riding comfort evaluation index for joint road which appears at freeway in USA typically in Los Angels as a part of rearrangement of objective evaluations on riding comfort of passenger vehicle. The bodily feel characteristics resulting from the survey were utilized for the evaluation index, also the comparison with bodily feel characteristics specified in ISO^1)~3) was made.

The various verifications demonstrated that the evaluation index is perfectly consistent with the subjective evaluations.

A new measuring method which enables quantitative force evaluation for the ride comfort analysis has been developed. The force transmitted from road surface to tire has been measured while the vehicle is running.

The result of the measurement has shown that the force transmitted from road to tire has certain direction of action in side view, within the frequency range between 5 and 15Hz. And the inclination angle of the direction of action has been found to be dependent on the vehicle velocity.

As the application of the measuring technique, the optimal wheel center locus inclination angle in side view, which minimizes the fore and aft force transmission from vehicle suspension to the body, has been studied. And the optimum angle has been confirmed to exist.

Concerning the Sn-Pb eutectic solder that is used most frequently as electric joint material, we have evaluated the reliability of five kinds of degradation modes. (① Thermal fatigue ② Intermetallic compound layer fracture ③ Creep fracture ④ Vibration fatigue ⑤ Migration).

Adopting the reliability engineering method, first,the mechanism of degradation was investigated, then the accelerated test method and characterstic parameter were fixed.

On the basis of the establishment as above, the accelerated test was executed under several conditions to find the stress dependency and the solder degradation was modeled.

While the enviromental stress frequency was obtained and they were put together by using a minor method, which enabled us to fix the accelerated test condition that was needed to guarantee the life of solder.

It's possible to form spark discharge on ignition parts, connection lines and contact points of electrical transmission parts used in car. The spark discharge forms nitrogen oxide (NOx) and ozone (O₃) by way of gasous products generated by discharge in air. NOx and O₃ react with water vapour (H₂O) in the atmosphere and cause to form nitric acid (HNO₃). HNO₃ is an important factor product to damage electrical transmission parts. Particulary, it has a possible case of damage on grease applied in ignition parts and a kind of switch. But there are few precedent for the quantitative estimation concerning how grease is damaged.

In this reserch, we visualized the sample greases and observed time change of those oil survival ratios through the experiments on exposure by the discharged gasous products and the heat-cool cycle, and clarified grease deterioration mechanism and speed quantitatively. And moreover as the countermeasure for the deterioration, we proved the necessity of the no-formation structure or the ventilation for NOx, O₃, etc. that are the origin of the grease deterioration.

Evaluation of the corrosion resistance of new coatings is often time consuming with currently accepted methods.

This research focused on developing a new accelerated test method for determining the quality of organic coatings. A practical coating test equipment “DECT”, using cathodic disbandment was developed.

Though a hydrogen absorbing capacity of intermetallic TiFe alloy is about 1.5 times as large as that of LaNi₅ alloy, TiFe alloy actually has not been commercialized for its difficulty in an initial activation treatment. Authors intend to improve the characteristic of TiFe alloy by partial substitution of the Fe with Pd having superior catalytic and hydriding natures. It has been confirmed that the partial substitution by Pd for the Fe is much effective for mitigating the initial activation condition of TiFe alloy.

A reduced nickel content heat-resistant alloy NCF3015 was developed to replace the nickel-base superalloys for exhaust valves applicable to unleaded gasoline only.

This alloy has superior high temperature strength and microstructural stability after long term use. This was obtained by increasing the amount of gamma-prime phase and optimizing additional elements.

This alloy has been employed in the exhaust valves for Logo at 1996 model.

High strength and good plasticity material is necessary for reducing size and weight of valve springs. The authors have reconsidered the chemical composition of material, modified the texture of carbides and developed a new surface softening (decarburization) process. As a result, more than 30% improvement of strength and the same plasiticity as that of conventional materials were obtained.

In the case of connecting rods for general purpose engines, aluminum alloy die castings are popularly used. Powder Metallurgy (P/M) forged Al-Si alloys for connecting rods have been developed aiming at weight and size reduction as well as high reliability compared with the conventional rods.

P/M forged Al-Si alloy for connecting rods were made by mixing metal powders such as Al, Cu,AlSi,and Al-Cu. As a result, wear resistance improves remarkably by dispersing Si particles as spots and optimization of the Si perticle size. Furthermore elongation is increased by adding trace transition elements and artificial aging. High fatigue strength is also obtained by the process of liquid phase sintering and forging that makes fine composition and less failes. Connecting rods made from these materials are found to be 30% thinner and 50% lighter than that of conventional die casting.

Thus, smaller sized, lighter weighted engines could be designed by making related crank shafts and cases more compact.

Zinc phosphate process with high corrosion resistance is developed as the surface treatment of aluminum-steel hybrid automotive body.

Copper contents of aluminum alloy, concentration of fluoride in zinc phosphate solution and composition of anti-corrosion pigment in E-coat are optimized to improve the corrosion resistance of aluminum alloy sheet. Analyzing the surface of the zinc phosphate film, it is found that fluoride on the zinc phosphate film reduces the adhesion of paint film and that chrome rinsing is necessary to improve the adhesion.

The new zinc phosphate process, which we developed, achieved simultaneous treatment for steel and aluminum body. And the surface treatment process productivity was improved.

Bumper facia requires high impact resistance. It is difficult to achieve thin wall facia at the same time. It was difficult to improve modulus of PP with high impact resistance.

To clear these requirements we studied PP formulation and paint with new structure. We have developed high modulus PP which has high impact resistance and also achieved lower weight and lower cost bumper facia system.

We controlled stereospecific polymerization of the PP and to optimize rubber polymer contents and morpholgy of PP/EPR rubber blends. Also we improved paint's elastic modulus and its absorption into the PP/EPR morphology. We achieved 18% weight reduction and 35% cost reduction by this thin wall bumper facia technology.

The history of the Honda side protector molding systems is dominated by the utilization of PVC and the extrusion molding process. The application of the gas assist injection molding process opened up possibilities in new application areas such as the side protector molding for which the extrusion molding process has been the previous process of choice. Whereas the extrusion process used PVC type materials the new product using the gas assist injection molding process uses TPO. The product resulted in a lighter, more aesthetic and lower cost part which also, by virtue of PVC elimination, is more environmentally friendly. This paper discusses the development of the material and the application of the new gas assist molding process which were necessary in the realization of the new gas assist injection molded side protector molding introduced in the 96 model year Civic and Accord. The future direction for this application is also discussed.

We have developed the new inexpensive substrate for headliner. That is possible to reduce cost with simple molding process.

The newly developed substrate is made by reducing the weight of KP sheet, which was used as a base of the substrate, and giving adhesion properties to the top coat and unbreathable properties to prevent it from breathing soil. KP sheet is the product of K-PLASHEET Co., Ltd. and manufactured by the paper making process using the materials of glass fibre and polypropylene powder. The substrate is capable of trimming in the molding process with short time.

An algorithm for post processing of radar signal on automobile is introduced, which estimates a movement of objects and keep frack of objects by Kalman filter and data structure which deals with multitarget. It can remove an influence of noise from object's shape and own pich or role motion. It can also detect positions of other cars and obstacles on the road by image processing data fusion.

This algorithm has been effective on an experimental automobile system which used its output for the action-decision making algorithm. Following forward car, obstacle avoidance and mixture running with other cars have been realized.

The styling CAD system capable of coping with a complex curved shape in a short term development of many models was developed to shorten a production period of master model and metalic mold for exterior parts of motorcycles, and to enhance their appearance. The high speed and high quality numerical data processing for curved surfaces of the clay model was realized by the semi-automatically forming and modifying method for curved shapes based on the data structure and processing architecture of object directional. The curved shapes data was also used for layout design and CAE analysis as basic data in motorcycle development, and contributes to enhance the development efficiency by linking three dimensional data.

Wearing mechanism of electrode on aluminum spot welding was analyzed to increase weldability of aluminum alloy sheets. The reduction of weldability results from the local deformation of the electrode tip and the reduction of the contact area, caused by alloy-phase ( θ phase: CuAl₂) which is formed between the tip and the sheet, and MgO which is pick upped from the sheet and deposited on the tip. Therefor, to make the electrode life longer, heat at the top of the tip should be controlled by increasing the conductivity of the tip material. By the same way, proper value ranges are set up on various conditions for the aluminum spot welding.

Generally, front and rear window glass (hereafter referred to as “glass”) are attached to the body by an adhesion system which is called “direct glazing method”. The adhesion system is important for safety since it must prevent the glass from coming off and must maintain assembly appearance. In the new bonding system, we developed a sealant material which can temporally support the glass, high quality machine for bonding glass (HONDA ENGINEERING CO., LTD.) and new windshield molding construction. We eliminated all glass supporting parts for assembly and developed an automated glass bonding process. As a result, we achieved improvements in overall glass assembly quality, simplification of process and cost reduction.