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This paper describes a computer-controlled engine test cell being developed at the General Motors Research Laboratories. The object is to combine the advantages of the controlled experimental conditions possible in an engine test cell with the dynamic capabilities of a vehicle driven on the road or on a chassis dynamometer to produce a unique research and development tool. The overall system, consisting of an IBM 1800 process control computer linked to an electric dynamometer and engine in an engine test cell, is introduced. A description is given of the test cell control and data acquisition instrumentation and of the pallet system which permits prebuilding of engine experimental packages for rapid installation in the test cell. An overview of the computer programs, with emphasis on user interaction, is presented. The throttle and speed control algorithms, which apply road or chassis dynamometer load conditions to the engine in the engine test cell, are discussed.

“Smooth road shake” complaints resulting from tire and wheel nonuniformities have been greatly reduced on original equipment tires. However, the problem still exists on after-market tires that have not been ground. The On-Car Tire Grinder (OCG) was developed by General Motors Research to provide a means for correcting smooth road shake complaints in the field. The device effectively duplicates the grinding done on original equipment tires. It has a low initial cost, does not require removing the tire from the car, and has proved practical for service use. Several companies have been given a free license to manufacture the On-Car Grinder for sale to tire stores and automobile dealers.

A number of tires have been examined in terms of the higher orders of radial and fore-and-aft force variations. Presented in this paper are some typical values of higher orders as measured on a specially designed high-speed machine. These measurements are related to the following factors: 1. Tire operating conditions. 2. Tire construction variations. 3. Influence of wheel and balance. 4. Radial force correction. 5. Ride evaluation. With experience, emphasis has shifted to understanding how tire manufacturing introduces higher harmonic disturbances, and thereby improving tire production, and making better use of conventional uniformity grading equipment.

This paper covers the features of rotary engines with charge-cooled rotors developed by Yanmar Diesel Engine Co., Ltd. It includes test results obtained with charge-cooled rotors during the course of development of the engine with this feature. With continuing new applications of the NSU/Wankel rotary engine, charge-cooling appears to be a promising feature, especially in small-sized engines, from the point of view of simple structure and improved economy.

The role of a systems house in implementing a system for a manufacturing complex can best be illustrated by the neutral position that a systems house will take in integrating the management requirements in relation to the real-time data base, which must be implemented from the manufacturing floor.

Discussion of the rotary-combustion engine's history, operation, and lubrication illustrates the role of various quality level engine oils in providing the necessary functions of engine seal wear protection, bearing lubrication, rotor cooling, and overall combustion chamber area cleanliness. Specific examples of current quality and experimental-type engine oil influence on overall engine durability, including seal and housing surface wear, are cited for various engine designs. Data evaluating lube oil effects on engine cleanliness and oil consumption characteristics are also discussed. Analysis of used oil from a number of test engines is presented showing the rotary-combustion engine to yield oil deterioration typical of current piston engines.

Industrial practices can cause consumer confusion. The failure to communicate between the highest levels of automotive and petroleum companies provides an example. Gasoline is taken for granted by the driving public. It is extremely toxic and its emission products are a major contributing factor to air pollution. Engineers know how automotive and gasoline problems are interlocked. The Clean Air Act has forced scientists and engineers to cooperate. Technological solutions and cleanup timetables are insurmountable only when this collaboration is missing. The substantiation of gasoline advertisements, trade secrecy, standardization, and lead consumption are also covered in this paper. To preserve a safe and pollution-free environment, the scientist and the engineer both have a duty to anticipate toxic and unsafe products and company practices.

MECAR (Metropolitan Engineers Council on Air Resources), organized in 1965 to represent the engineering profession through its various societies in the New York metropolitan area, has four objectives: 1. To advise on standards and formulation of laws to improve air quality. 2. To serve law enforcement agencies in an advisory capacity. 3. To alert city, county, regional authorities, and the general public to pollution problems. 4. To inculcate within the engineering profession the need to cope with the sociotechnical problem. The group attempts to maintain consistency of direction of policy in matters pertaining to air quality in metropolitan areas.

The premise of this paper is that many of the problems facing society are technological at heart, and can be solved only by the application of better technology by technologists. Further, it is the duty of technological organizations to present and publicize impartial, balanced advice to the public and government as to the best courses of action to pursue. The author illustrates his hypothesis by taking three areas as examples, namely, the population explosion, the eutrophication of lakes, and automobile emissions. For each, he examines currently disseminated information, points up inaccuracies in much of this information, and suggests avenues to be explored in working for solutions.

Over the past few years there has been a growing interest in the applications of isocyanate-based structural foams (Dermathane). Molds and tooling are critical to making a good article. Experience is the principal teacher in this area of technology. An analysis of various toolings and applications tells what is necessary and what is unnecessary. Density is well-known as the most important variable when strength is considered. However, when sandwich-like structures are involved, the analysis for strength becomes more complicated. This paper includes all the processing and design information necessary for using Dermathane at the optimum strength and economy.

Polyolefin structural foams have the potential for large usage in the automotive industry because they have all the attractive properties of the solid polyolefins, plus greater rigidity at a lower cost for molds and molding machinery. The advantages to the automobile manufacturer include: lighter vehicle weight, lower cost, better balance to offset safety and antipollution devices, greater collision safety, noise reduction, better resistance to corrosion, and a smoother ride. Preliminary designs and economic studies were performed for several automobile parts including bucket seats, hoods, rear deck lids, dash panel inserts, air-conditioner housings, etc.

COMMODITY STRUCTURAL FOAM MATERIALS FOR AUTOMOTIVE APPLICATION Structural foam plastic materials are increasingly being used in engineering functions as well as in areas where styling and aesthetics are important. Recent developments in plastic part designs and in processing research point toward significantly increasing uses of structural foam for automotive and truck applications. Plastic structural foam parts are now being molded that are as large as 12 feet in the longest dimension. Existing molding equipment will allow part weights as great as 100 pounds to be processed. It is technically feasible to mold passenger compartment-sized parts with the present state of the art. Physical property data for structural foams are presented to assist designers and engineers in their work.

Tire force and moment test machines are used to measure mechanical properties important to vehicle handling. Many different machines have been developed for this type of work. This report discusses considerations in the design of such equipment which include productivity, road simulation, tire size range, input parameters, weighing system design, and data processing. The design of a new test machine with a belt type road simulator is described. Some early test data on machine correlation, lateral force and aligning torque dynamics, and flat road uniformity are presented.

The ability to view the tire footprint and simultaneously to measure the tire-to-road surface interface forces is essential to the investigation of parameters affecting high-speed passenger tire performance on wet surfaces. The tire is photographed from below through a glass plate; the tire-to-road surface inter-face forces are recorded for various combinations of tire types, inflations, loads, wear conditions, water depth, and vehicle velocity as the tire passes over a triaxial force pin. The facility and test method are described for the evaluation of pneumatic tires at all modes of operation: free rolling, sliding, and free rolling with a slip angle. An empirical equation is given to estimate the hydroplaning speed of a passenger tire on a smooth surface in a single mode (free-rolling) of operation. The parameters that affect tire hydroplaning are discussed as are some of the conditions that may influence the method of test.

There is a growing need for specialized road surfaces in order to conduct a variety of tire and/or vehicle tests. This need arises in such areas as vehicle and/or component testing required by various Department of Transportation standards, dynamic calibration surfaces for road-monitoring “skid trailers,” and comparison of tires at multiple sites on a common basis. Surfaces which would fulfill this need should meet the following objectives: 1. Be entirely prescribable, utilizing easily obtainable components and simple construction techniques. This would assure that any organization could produce a desired surface with confidence of specific and repeatable results. 2. Provide the desired frictional characteristics. These could be “real world” surface characteristics, or a specific set of characteristics required as a particular test parameter. 3. Exhibit reasonable durability.

This paper summarizes the highlights of developments of the rotating combustion (RC) engine at Curtiss-Wright Corp. in each of several principal areas; speculates on remaining directions, both within and without the framework of previous explorations; and briefly describes germane technical features of the engines used in commercial applications of other licensees. At the same time an attempt has been made to span gaps left by previous papers or publications and to expand material considered proprietary earlier. Design features, testing, and ramifications of the RC1-60 rig engine are examined in detail. The application of the fundamentals and principles of the RC engine to automotive, air-craft, and small, air-cooled engines is also described.

The Inter-Industry Emission Control (IIEC) Program included the thermal reactor as one of the effective ways of oxidizing HC and CO in the exhaust system. However, this was accompanied by very substantial fuel economy penalties, especially in the case of small engine-low emission concept vehicles. Starting with a new concept aimed at obtaining the HC/CO oxidizing trigger temperature in the thermal reactor by modifying engine settings, the authors arrived at an economical technique of matching the thermal reactor to the engine.

During the past four years, Mitsubishi Motors Corporation has been active in the design and development of catalytic converter systems in the IIEC Program. Experience indicates that an effective dual catalytic converter, consisting of a NOx catalyst and a HC/CO catalyst, is indispensable to achieve the stringent IIEC targets, established on the basis of 1976 Federal Standards. However, there still remains a major difficulty of meeting the NOx target since NO is regenerated in the HC/CO catalyst in the dual converter system. This paper describes our major efforts in seeking a breakthrough to control the NOx emission, and covers some noteworthy findings on transient NO concentrations at the inlet and outlet of HC/CO converter in an experimental dual converter.

A test procedure to determine the conversion performance of oxidation and reduction catalysts for the treatment of automotive engine exhaust gases is described. The variable parameters are the air/fuel ratio, the secondary air quantity and the space velocity. The results are recorded in diagrams which permit the selection of optimal catalysts with reference to the conversion and which also form the basis for the lay-out of the necessary devices for controlling air/fuel ratio and secondary air. Characteristic results with noble metal catalysts on monolithic supports and pelleted base metal catalysts are shown.

During vehicle cold start, emissions, mass flow rates, and catalytic converter space velocities vary by orders of magnitude. Therefore, catalytic exhaust control systems must be designed to operate at high efficiency almost from the moment of engine start-up. Catalysts must reach their operating temperature as quickly as possible. Therefore, the utility of different methods for improving the warm-up characteristics of catalytic systems is illustrated. A very elegant method to speed the warm-up is the use of the engine itself as a “preheater” for the catalytic converters. High exhaust gas enthalpy to raise exhaust system mass up to its operating temperature is obtained by the use of extreme spark retard, stochiometric mixtures, and fully opened throttle. Intensive studies to investigate the effects of concurrent changes of spark timing and air/fuel mixtures on exhaust gas temperature, enthalpy, NOx and HC emissions are discussed.