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The development of the AUTO TEMP II Temperature Control System used in Chrysler Corp. vehicles is summarized. A description of the design, development, function, and manufacturing aspects of the control system is presented, with emphasis on unique control parameters, reliability, serviceability, and check-out of production assemblies. Auto Temp II was developed by Chrysler in conjunction with Ranco Incorporated. The servo-controlled, closed-loop system, which has a sensitivity of 0.5 F, utilizes a water-flow control valve for temperature control, along with a cold engine lockout. The basic components are: sensor string, servo, and amplifier. All automatic functions involving control of mass flow rate, temperature, and distribution of the air entering the vehicle, are encompassed in one control unit. All components are mechanically linked through the gear train and are responsive to the amplifier through the feedback potentiometer.

The paper outlines testing, development, and operation of the first production four-wheel slip control system for passenger cars in the United States. The Chrysler Corp. calls the system “Sure-Brake,” but it is more generally known as “anti-skid.” The first portion of the paper deals with considerations that led Chrysler into the Sure-Brake system, the philosophy behind the system, and a detailed explanation of its operation. The second portion deals with the development and testing of the system, leading to its release as an option on the 1971 Imperial. The testing program introduced a new dimension to brake engineering. Before the advent of wheel slip control systems, many thousands of brake tests were conducted but were always terminated at the point of skid. These tests were also conducted mainly on black top or concrete roads. For the first time, thousands of stops were made at maximum deceleration on every available surface.

THIS paper describes the springs, control system, and ride of the air suspension system on the 1958 Buick. The system is a semiclosed one, providing a variable-rate suspension, automatic leveling and trim control, and manual lift. The latter feature is a knob below the instrument panel which can be operated when necessary to cope with unusual clearance conditions. The car remains at the same height with loads of up to five passengers and 500 lb in the trunk. The authors describe the road-holding ability of a car with this suspension system as excellent.

Two-stage turbochargers are a recent solution to improve engine performance, reducing the turbo-lag phenomenon and improving the matching. However, the definition of the control system is particularly complex, as the presence of two turbochargers that can be in part operated independently requires effort in terms of analysis and optimization. This work documents a characterization study of two-stage turbocharger systems. The study relies on a mean-value model of a Diesel engine equipped with a two-stage turbocharger, validated on experimental data. The turbocharger is characterized by a VGT actuator and a bypass valve (BPV), both located on the high-pressure turbine. This model structure is representative of a “virtual engine”, which can be effectively utilized for applications related to analysis and control. Using this tool, a complete characterization was conducted considering key operating conditions representative of FTP driving cycle operations.

The complexity of designing and implementing a vehicle electrical control system for ultra fuel-efficient hybrid vehicles is significantly greater than that of a conventional vehicle. To quickly demonstrate and iterate capabilities of these vehicles, an efficient and rapid means for developing requirements, mapping these into an electrical control and communications architecture, and developing prototype systems is needed. The General Motors Precept concept vehicle is an example of an energy- efficient vehicular control system developed using a "requirements to software'' development process and electronic controller infrastructure that demonstrates these attributes. The Precept is General Motors Corporation's technology demonstration concept vehicle developed to address General Motors Corporation's commitment to the Partnership for a New Generation (PNGV) program.

General Motors introduced a family of small front wheel drive six speed automatic transmissions for the 2008 model year. The family currently has two variants: 6T40 and 6T45, which cover a range of vehicles from small & compact cars to small SUVs and handle engines torque capacities up to 240 Nm Gas(280 Nm Diesel) & 315 Nm Gas (380 Nm Diesel) respectively. The 6T40/45 transmissions replace GM traditional four speed automatic wrap around transmissions 4T40/45. The wrap around transmissions have Torque Converter, Pump & Controls on the engine axis and the rest of the transmission content on the output axis. The 6T40/45 have an on-axis architecture with majority of the transmission content on the engine axis and final drive & differential on the output axis. The 4T40/45 have input chain transfer whereas the 6T40/45 have an output chain transfer.

Allison Gas Turbine Division of General Motors is performing the first phase of a multiphase development project aimed at demonstrating an electric vehicle based on a proton exchange membrane (PEM) fuel cell. This work is sponsored by the Office of Transportation Technologies of the U.S. Department of Energy (DoE) through the DoE's Chicago Field Office (Contract No. DE-AC02-90CH10435). This work complements major efforts under way to produce electric vehicles for reducing pollution in key urban areas. Battery powered vehicles will initially satisfy niche markets where limited range vehicles can meet commuter needs. The PEM fuel cell/battery hybrid using methanol as fuel potentially offers an extremely attractive option to increasing the range, payload, and/or performance of battery powered vehicles.

Electronics suitable for engine control applications has steadily evolved from analog control systems to microprocessor based designs. The change in technology required in switching from analog to microprocessors has required sensor development, new analog to digital conversion techniques, and development of custom input/output circuits suitable for automotive applications. By proper design of the microcomputer system, an engine control unit can be developed that is cost effective compared to conventional analog circuit techniques while providing additional flexibility. The primary limitation of a digital approach is the long lead time required to change the ROM pattern. This lead time can be reduced by combining PROM and ROM in the same system.

A system for controlling gasoline evaporation losses from 1970 model Chrysler Corp. cars and light trucks was developed, certified for sale in California, and put into production. Evaporation losses from both the carburetor and the fuel tank are conducted to the engine crankcase for storage while the engine is shut down. The vapors are removed from the crankcase and utilized in the combustion process during subsequent vehicle operation. Particularly interesting in this unique, no-moving parts system, are the reliability and durability, and the vapor-liquid separator “standpipe.”

TURBOGLIDE is the deluxe automatic transmission of the General Motors Chevrolet. One of its most important features is that its performance ratio is available at any throttle position, enabling control of torque ratio and engine output by the throttle pedal. The system includes a five-element torque converter, pump, three turbines, and the dual stator. The entire installed unit weighs 148 lb, a result of the general arrangement and the use of aluminum in the case and bell housing. The authors discuss the basic operating principle of the transmission, the arrangement, performance, torque distribution, control system, and valve body.

This paper describes the recent efforts on developing an automotive climate control system throughout integrating an electrically-controlled variable capacity scroll compressor with a fuzzy logic control-based refrigerant flow management. Applying electrically-controlled variable capacity compressor technology to climate control systems has a significant impact on improving vehicle fuel economy, achieving higher passenger comfort level, and extending air and refrigerant temperature controllability as well. In this regard, it is very important for automotive climate control engineers to layout a system-level temperature control strategy so that the operation of variable capacity compressor can be optimized through integrating the component control schemes into the system-level temperature control. Electronically controlled expansion devices have become widely available in automotive air conditioning (A/C) systems for the future vehicle applications(1, 2, 3 and 4).

The development and application of a traction control Kodiak and GMC TopKick are explained. Most traction systems use engine management to enable traction control, while the adaptive braking system can provide traction assist for either gas or Diesel powered vehicles from 14,000 lbs. to 33,000 lbs. GVW. The performance driven criteria that established the design requirements and the development of a new product to meet these objectives are discussed. Both the vehicle manufacturer and the traction controller supplier provided these criteria. The basic ABS and traction control hydraulic schematics will be described as they apply to the vehicles. The results of the development program will be compared to the criteria used to establish the goals, and the benefits of the traction control system will be discussed.

This paper describes an absolute stability analysis of idle speed control systems. Current idle speed control systems make use of both spark advance and the idle air actuator to control engine speed for improved response relative to variations in the target idle speed due to load disturbances. The control system at idle can be presented by a multiple input multiple output (MIMO) model [1]. Control system design is usually done based on linear or linearized models [2,3,4]. However idle speed control systems are nonlinear because of the saturation of the actuators. This paper describes an application of the absolute stability theory to idle speed control systems with saturation of actuators.

THIS description of the hydraulic control used with the hydra-matic transmission reveals how the control operates to change ratios under power without direction from the driver. The control's pattern of automatic shifting for ordinary, high-range driving has been selected as the best compromise between top performance and low ratio of engine noise to wind noise. The control's low range shifts gears according to performance dictates alone, furnishing greater power for extreme conditions at low speeds and enabling the driver to use his engine as a brake on steep descents. Heart of the control system is a double hydraulic governor, sensitive both to car speed and throttle opening. THIS paper, as well as the two that follow, one by Messrs. Nutt and Smirl and the other by Mr. Kimberly, make up a symposium on automatic transmission components presented at the 1947 SAE Summer Meeting.