Abstract: The present invention relates to a motor vehicle navigation method and system (10). More specifically, this system comprises a central navigation computation unit (11) equipped with a memory (12) containing the topography of a predetermined zone, and a device (13) for locating the vehicle. The central unit (11) is associated with a voice-guidance device (15) and a screen (14) operating in a mode known as “normal guidance” mode, in which at least one direction pictogram is displayed on the screen to indicate the major maneuvers which have presently to be reproduced by the driver.

Abstract: The device comprises transistors (T1, T2, T3, T4) each connected in series with one of the phases (.phi.1, .phi.2, .phi.3, .phi.4) of the stator of the motor in order to control its power supply by an electrical energy source (+V.sub.BAT). Means (D1, D2, D3, D4) are provided for detecting the simultaneous stopping of conduction in all of the phases and to then control the return to conduction of one of the phases (.phi.4), by an appropriate control of a transistor (T5), in order to lock the rotor with a predetermined holding torque established by this phase. Thus, in the case of a failure of the control of the phases of the motor, the motor remains substantially immobile even if it is subject to the action of a parasitic or resisting torque.Application to a motor for controlling the butterfly valve for the gases of an internal combustion engine.

Abstract: In this system, the units are capable of transmitting and/or of receiving messages in at least a first format by way of a channel (A). Circuitry included in at least one of these units (B, M) are provided for transmitting on the channel (A), in a second format distinct from the first format, a message for putting the other electronic units (M) into operation.

Abstract: A device for the production of a tachometry signal of infinite resolution and without ripple from an inductive position sensor. The sensor is fed by a sinusoidal reference signal and supplies two phase signals. A resistance-capacitance circuit tuned to the frequency of the reference signal is fed by the two phase signals of the sensor and supplies a sinusoidal signal whose phase angle is proportional to the rotation of the sensor. This signal is then digitized and processed by digital phase comparators and low-pass filters before differentiation. This includes the use of particular digital phase comparators, each associated with a particular return to zero detector, to produce by a storage flip-flop and an electronic switch, the outgoing tachometry signal with the aid of a single differentiator with a device for elimination of discontinuities.