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This paper offers a brief explanation of Isuzu Transport Auto Control (I-TAC), a system used to accurately collect and control information in-transit. I-TAC was developed as a means to meet needs for transportation by truck.

The growing need for improved fuel economy is a global challenge due to continuously tightening environmental regulations targeting lower CO2 emission levels via reduced fuel consumption in vehicles. In order to reach these fuel efficiency targets, it necessitates improvements in vehicle transmission hardware components by applying advanced technologies in design, materials and surface treatments etc., as well as matching lubricant formulations with appropriate additive chemistry. Axle lubricants have a considerable impact on fuel economy. More importantly, they can be tailored to deliver maximum operational efficiency over specific or wide ranges of operating conditions. The proper lubricant technology with well-balanced chemistries can simultaneously realize both fuel economy and hardware protection, which are perceived to have a trade-off relationship.

Every year the trucking industry demands lighter weight and lower cost truck components. But it is very difficult to achieve both these targets. This paper describes the example of a suspension system design which was conducted by computer simulation, so called CAE. The computer simulation by FEM was used completely to decide the detailed shape of each part. This paper also introduces a casting method to strengthen the aluminum alloy cast using high pressure during casting. By using this method, products have a precise metallographic structure. As a result, both the development cost and period were reduced by over the half the time required of the current system and lighter and strong parts were created.

It is becoming more and more complex and time consuming to have a newly developed vehicle meet the safety requirement these days. On the other hand, with the aid of computers and software technology, detailed crash simulation are possible. ISUZU MOTORS LTD. has applied these to the passenger car from the early stages of development in order to optimize the car's behavior in the 35MPH frontal barrier test. Crash simulations were performed by using the detailed full vehicle FEM model and the crash simulation program PAM-CRASH. This simulation focussed on the collapsing mode of the front structure, especially on the front of the side rails and the attached parts. Section forces, accelerations, and deformed shapes were investigated and optimized to improve energy absorption. The effect was confirmed by the experimental barrier test. This procedure contributed greatly to reducing the time required for development as well as the number of prototype vehicles needed.

When a heavy duty truck with 2 rear axles is turning a curve at slow speed, a large side bending force to the chassis frame occurres as vehicle turning radius becomes smaller. In the past, the stress produced by side bending forces was little analyzed. By our research work of FEM, side bending stress of heavy duty truck could be analyzed accurately.

To check sharply increasing traffic accident casualties, activities have been underway to analyze accidents and develop safety equipment Automobile makers have placed a great emphasis on improving safety in collision. In this situation, a new side impact standard was introduced in FMVSS 214 in October 1990 and will be applied to passenger cars in 1993 model year. The standard requires an additional full scale dynamic test in which an aluminum honeycomb moving deformable barrier (MDB) simulating the front end of a car is crashed at 33.5 mph into the side of a standstill car at an angle of 27 degrees. The Side impact Dummy's (SID) Thoracic Trauma index (TTI(d)), which is the average of the maximum rib acceleration and the maximum lower spine acceleration, is limited to 90 g's for a 2-door passenger car and 85 g's for a 4-door car. The dummy's pelvic maximum acceleration must remain no greater than 130 g's for both types of cars.

GVW 20 ton class cargo trucks were mainly powerd by L6 turbocharged engines ISUZU 6SD1TC and ISUZU 6RB1TC, and this time new 6WA1TC turbocharged engine with intercooler as a successor to 6RB1TC went into production in July 1992. In the recent cargo vehicle market in Japan, demand is increasing for higher out-put power, light weight, long service life, high reliability and low fuel consumption. Under such circumstances special engineering attention was paid to exhaust emissions and noise regulations which are expected to become even stricter in future. The basic engine structure consists of an OHC 4-valve type cylinder head and a ladder frame type cylinder block which satisfies the requirements for the high out-put power, low fuel consumption and light weight. Also, adopted are various variable structures such as a high pressure fuel injection pump with a variable injection timing and rate control device, variable swirl system and variable geometry turbocharger.

This paper shows one example of cooling system, optimized by utilizing computer simulation in the early development stage. First, a numerical simulation is conducted to obtain the air flow rate through engine compartment room by the software “STREAM”. Second, ΔTw are calculated by the software “KULI”, developed by Steyr-Daimler-Puch AG, to evaluate the original cooling system. Third, the optimization of this system is conducted by the design of experiment for cost saving and weight reduction. The test value was well matched with the calculated one and CAE was confirmed to be very helpful for saving the proto-build cost and time period.

Vibration behavior of a crankshaft in operation is complicated and difficult to simulate because of oil effects on journals, coupled vibration of crankshaft system parts, combustion and inertia acting on the crankshaft. Particularly, the stiffness and damping of oil film vary with crank angles and thus the numerical analysis must deal with nonlinear vibration. This oil film effects also diversify the vibration modes of the crankshat; the vibration modes in an actual operation differs from that in statically experiment modal analysis. This paper describes a new method developed by the author to analyses, predict, and reduce noise and vibration using several techniques including numerical simulation, finite element method, Sommerfeld concept on oil film effects, and modal frequency response.

Two working groups in the JSAE Committee of Fatigue–Reliability Section1 are currently researching the issue of fatigue life by both experimental and the CAE approach. Information regarding frequent critical problems on arc–welded structures were sought from auto–manufacturers, vehicle component suppliers, and material suppliers. The method for anti–fatigue design on arc–welded structures was established not only by a database created by physical test results in accordance with the collected information but also with design procedure taking Fracture–Mechanics into consideration. This method will be applied to vehicle development as one of the virtual laboratories in the digital prototype phase. In this paper, both the database from bench–test results on arc welded structures and FEA algorithm unique to JSAE are proposed some of the analysis results associated with the latter proposal are also reported.

In fleet uses, heavy-duty trucks with turbo, inter-cooled engines are popular in Japan. These trucks usually experience congested traffic and/or frequent road grade change in expressways. As a result, frequent vehicle speed and engine load fluctuations are observed. This paper describes the typical, on road driving data from the field and presents one sample of engine control optimization for better fuel economy in actual road conditions.