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This paper describes the design and implementation of the SEA, Ltd. Brake and Throttle Robot (BTR). Presented are the criteria used in the initial design and the development and testing of the BTR, as well as some test results achieved with the device. The BTR is designed for use in automobiles and light trucks. It is based on a servomotor driven ballscrew, which in turn operates either the brake or accelerator. It is easily portable from one vehicle to another and compact enough to fit even smaller vehicles. The BTR is light enough so as to have minimal effect on the measurement of vehicle parameters. The BTR is designed for use as a stand-alone unit or as part of a larger control system such as the Automated Test Driver (ATD) yet allows for the use of a test driver for safety, as well as test selection, initiation, and monitoring. Installation in a vehicle will be described, as well as electronic components that support the BTR.

This paper describes the design and development of the hardware, electronics, and software components of a state-of-the-art automated steering controller, the SEA, Ltd. ASC. The function of the ASC is to input to a vehicle virtually any steering profile with both high accuracy and repeatability. The ASC is designed to input profiles having steering rates and timing that are in excess of the limits of a human driver. The ASC software allows the user to specify steering profiles and select controller settings, including motor controller gains, through user-interface windows. This makes it possible for the test driver to change steering profiles and settings immediately after running any test maneuver. The motor controller used in the ASC offers self-contained signal input, output, and data storage capabilities. Thus, the ASC can operate as a standalone steering machine or it can be incorporated into typical existing, on-vehicle data acquisition systems.

This paper describes the design and operation of a facility for measuring vehicle center-of-gravity height; roll, pitch, and yaw moments of inertia; and roll/yaw cross product of inertia for a broad range of test specimens. The facility is configurable such that it is capable of measuring these properties for light, single axle trailers; long, heavy vehicles; and tank turrets. The design was driven by the need for accurate, repeatable measurement results and the desire to have a single facility capable of making measurements on a broad range of vehicle sizes.

This paper describes the design of a vehicle inertia measurement facility (VIMF): a facility used to measure vehicle center of gravity position; vehicle roll, pitch, and yaw mass moments of inertia; and vehicle roll/yaw mass product of inertia. The rationale for general design decisions and the methods used to arrive at the decisions are discussed. The design is inspired by the desire to have minimal measurement error and short test time. The design was guided by analytical error analyses of the contributions of individual system errors to the overall measurement error. A National Highway Traffic Safety Administration (NHTSA) database of center of gravity position and mass moment of inertia data for over 300 vehicles was used in conjunction with the error analyses to design various VIMF components, such as the roll and yaw spring sizes.

The Suspension Parameter Measurement Device Model 7547 (SPMD Model 7547) has been designed and built for the purpose of measuring displacements and forces acting on the road wheels of a vehicle. These displacements and forces may be due to movement of the vehicle body (kinematic), forces occurring in the plane of the road (compliance), or due to movement of the steering wheel (steering). The SPMD Model 7547 tests the entire vehicle as a unit and provides a “black box” determination of the suspension characteristics in terms of input/output relationships. This data can then be used in the simulation of the performance of light cars and trucks.

The purpose of this paper is to give a description of using the new type Suspension Parameter Measurement Device. The design philosophy and specifications are elaborated on in another SAE paper entitled “Design of a New-Type Suspension Parameter Measurement Device”. The importance of using this new machine will be addressed in this paper. Because of the ease of use for this new device, testing can be accomplished in hours. To check repeatability, repeat testing can be done in a short period of time. This rapid testing is the main advantage of the new generation of SPMD's. The new SPMD collects raw data from transducers. All data are stored in the computer. Some are used directly to generate graphic outputs. Some are utilized to calculate wanted parameters. Graphs are generated so that some characteristics can be scrutinized. Parameters can be presented either by points or by cross plotting in graphs.