Vehicle Sensor Power Circuit for Pre-Start Zero Point Correction

Solution Overview

Problem

Existing vehicular navigation systems face challenges in completing zero point correction of gyro and acceleration sensors before the vehicle starts moving, leading to incorrect direction estimation and user discomfort, especially due to voltage drops during engine cranking.

Innovation Solution

A vehicular apparatus with a first power supply circuit for multimedia devices and a second power supply circuit with a lower minimum operating voltage, enabling the power supply to sensors and a correction unit to start before the engine is activated, allowing zero point correction to be performed even when the vehicle is stopped.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a single power supply circuit with a fixed minimum operating voltage is used, then the system structure is simple, but the zero point correction cannot be completed before engine start due to voltage drops during cranking

Engineering Contradiction:

Improvezero point correction completionVSAvoidpower supply circuit structure

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The power supply system is divided into two independent power supply circuits: a first power supply circuit for multimedia devices and a second power supply circuit for sensors and correction units. This segmentation allows the second circuit to operate at lower voltages during cranking, enabling zero point correction to complete before engine start, while the first circuit maintains higher voltage requirements for stability.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different parts of the system are assigned different minimum operating voltage requirements. The second power supply circuit serving sensors and correction units has a lower minimum operating voltage than the first power supply circuit serving multimedia devices. This local differentiation allows critical correction functions to operate during voltage drops while non-critical multimedia functions wait for stable power.

Inventive Principle:

Principle #3Local quality

2Measurement precision

If the power supply starts before engine cranking, then zero point correction can be performed, but voltage drops during cranking may cause incorrect correction results

Engineering Contradiction:

Improveangular velocity detection accuracyVSAvoidzero point correction accuracy

Core Design Contradiction:

Measurement precisionVSReliability

Solution Approach 1:

The power supply system is divided into two independent power supply circuits: a first power supply circuit for multimedia devices and a second power supply circuit for sensors and correction units. This segmentation allows the second circuit to operate at lower voltages during cranking, enabling zero point correction to complete before engine start, while the first circuit maintains higher voltage requirements for stability.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The second power supply circuit is designed to start before engine cranking and maintain operation during the cranking period. This preliminary action allows the zero point correction to be completed in advance, before any voltage drops occur, ensuring both early execution and measurement accuracy by isolating the correction circuit from cranking-induced voltage fluctuations.

Inventive Principle:

Principle #10Preliminary action

3Stability of the object's composition

If zero point correction is delayed until after engine start, then power supply stability is ensured, but the vehicle direction cannot be correctly estimated causing user discomfort

Engineering Contradiction:

Improvepower supply stabilityVSAvoidvehicle direction estimation accuracy

Core Design Contradiction:

Stability of the object's compositionVSMeasurement precision

Solution Approach 1:

The power supply system is divided into two independent power supply circuits: a first power supply circuit for multimedia devices and a second power supply circuit for sensors and correction units. This segmentation allows the second circuit to operate at lower voltages during cranking, enabling zero point correction to complete before engine start, while the first circuit maintains higher voltage requirements for stability.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The second power supply circuit is designed to start before engine cranking and maintain operation during the cranking period. This preliminary action allows the zero point correction to be completed in advance, before any voltage drops occur, ensuring both early execution and measurement accuracy by isolating the correction circuit from cranking-induced voltage fluctuations.

Inventive Principle:

Principle #10Preliminary action

Data Source

PatentUS11858438B2Vehicular apparatus

Publication Date: 2024.01.02 DENSO CORP

AI summary

A vehicular apparatus includes a first power supply circuit, a second power supply circuit, a correction unit, and a sensor configured to detect an angular velocity or acceleration applied to a vehicle. The first power supply circuit is configured to perform a first power supply with a first minimum operating voltage. The second power supply circuit is configured to perform a second power supply with a second minimum operating voltage set to be lower than the first minimum operating voltage. The second power supply circuit is enabled to start the second power supply before an engine of a vehicle is started. The correction unit is configured to perform a process related to a zero point correction of the sensor. Herein, the sensor and the correction unit are configured to receive the second power supply from the second power supply circuit.