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In hybrid electric vehicles (HEVs) and full electric vehicles (EVs), efficient electrical power management with proper supply of power at the required voltage levels is essential. A DC (Direct Current)-DC converter is one of the key electrical units in a HEV/EV. The DC-DC converter dealt in the present work is intended to create the DC voltages necessary to power the accessories. The electronic circuit in this DC-DC converter consists of high power devices like Metal-Oxide Semiconductor Field-Effect Transistors (MOSFETs), inductors, transformers, etc. mounted on a printed circuit board (PCB). The DC-DC converter interacts with a high voltage battery pack and supplies a low voltage power to the accessory battery. Due to this power handling operation, the devices in the convertor experience high temperatures. The temperature rise of the devices beyond the permissible limits could be detrimental to an efficient and safe operation of the converter.

It has been demonstrated that multiple beam ranging can be achieved with a single camera and a spatially encoded probing beam matrix. However, as the density of the beam matrix increases, identification ambiguities among some of the probing beams may occur that will cause errors in triangulation ranging. This paper focuses on how to label the beams that are otherwise confused by the spatial encoding. An optimized system configuration is constructed to create unique regions in the image plane to enhance the probing beam identification. If needed, further discrimination is achieved using boundary conditions and adaptive thresholds. The system is demonstrated with 7×7 probing beams and a VGA CMOS camera.

A single camera and dot matrix structured light are used for target range measurement with optical triangulation. The probing beams are spatially encoded in the image plane so that each beam can be uniquely identified without confusion. Such an arrangement allows multiple probing beams in a single image frame to obtain target range profiles. Compared with either a stereovision system or an expensive range scanning system, the approach provided in this paper is more practical, efficient, and cost effective. Principles of spatial encoding, optimized optical configuration, beam labeling and system operation are described. The system is demonstrated with 4×7 probing beams and a VGA CMOS camera.

Rollover sensing and discrimination generally requires an algorithm that monitors vehicle motion and anticipates conditions that will lead to a rollover. In general, a deploy command is required in a time frame such that safety measures can be activated early enough to protect the occupants. A rollover discrimination system will typically include internal motion sensors, vehicle signals from other on-board sensors, and a microprocessor to execute the deployment algorithm. A supplemental signal path is used to arm the system, making it less susceptible to single point component failures. In this chapter we explore basic concepts of rollover sensors and system mechanization, rollover discrimination algorithms, and arming methodology. A simulation environment that models the performance of the system across part tolerance, temperature extremes and component age is used to estimate the scope of expected discrimination performance in the field.

A method of canceling unknown angular rate effects in impact immunity measurement for angular rate sensors is presented. A pair of the same type of testing sensors is arranged such that the sensing axes of the sensor pair are 180° out of phase. While an angular rate produces anti-phase component in the sensor outputs, a linear acceleration produces in-phase response from the sensors due to similar mechanical symmetry. This phase difference is used to cancel the angular rate component even though the actual angular rate may still be unknown. This cancellation can be derived from the sensor output transfer function and is supported with our experimental data.

This paper presents a test methodology for evaluating angular rate sensors used for detecting vehicle rollover. The key electrical parameters over temperature are tested with a rate table. Immunity to linear accelerations is evaluated at room temperature with a vibration table and a thruster. The vibration test provides mechanical resonance information and rough road performance, while the thruster test provides g-sensitivity parameters under severe impact conditions such as with vehicle frontal and side impact events. The vehicle level evaluation includes severe vehicle maneuvers, rough road and gravel road tests, as well as full-scale vehicle rollover tests.