In-vehicle device controller and power steering device

Patent metadata

Field	Value
Publication number	US-9975572-B2
Application number	US-201515111237-A
Country	US
Kind code	B2
Filing date	Feb 5, 2015
Priority date	Feb 24, 2014
Publication date	May 22, 2018
Grant date	May 22, 2018

Abstract

An in-vehicle device controller has at least two redundant operating condition detection units. Under normal circumstances, the controller performs actuator drive control based on an operating condition detection signal of one of the operating condition detection units. Upon detection of an abnormality in the signal transmission state, data state or operating status of one of the at least two operating condition detection units, the controller performs actuator drive control based on an operating condition detection signal of another one of the at least two operating condition detection units in which no abnormality is present. By this control, the actuator function is preserved even in the event of the abnormality in the operating condition detection unit or operating condition detection signal.

First claim

The invention claimed is:

1. An controller of an in-vehicle device with an actuator, the controller comprising:
an operating condition detection system that detects an vehicle operating condition and outputs first and second operating condition detection signals, said first and second operating condition detection signals being detected by and outputted from a plurality of respective detection elements or being detected by a common detection element and outputted through respective different electronic circuits;
a first abnormality judgment circuit that judges the presence or absence of an abnormality in the first operating condition detection signal and, upon detection of an abnormality in the first operating condition detection signal, outputs the first operating condition detection signal with abnormality data contained therein as an output signal;
a second abnormality judgment circuit that detects the presence or absence of an abnormality in the second operating condition detection signal and, upon detection of the abnormality in the second operating condition detection signal, outputs the second operating condition detection signal with abnormality data contained therein as an output signal;
an ECU that performs drive control of the actuator;
a signal abnormality detection circuit arranged in the ECU such that the signal abnormality detection circuit receives the output signals of the first and second abnormality judgment circuits and detects the presence or absence of an abnormality in the respective output signals of the first and second abnormality judgment circuits; and
an actuator control circuit arranged in the ECU such that, when the signal abnormality detection circuit judges that no abnormality data is contained in the output signals of the first and second abnormality judgment circuits, the actuator control circuit calculates and outputs a drive control signal for drive control of the actuator in accordance with at least one of the output signals of the first and second abnormality judgment circuits and such that, when the signal abnormality detection circuit judges that the abnormality data is contained in one of the output signals of the first and second abnormality judgment circuits, the actuator control circuit calculates and outputs the drive control signal in accordance with the other of the output signals of the first and second abnormality judgment circuits.

2. The controller of the in-vehicle device according to claim 1 , further comprising a redundancy monitoring circuit arranged in the ECU so as to detect the abnormality in the respective output signals of the first and second abnormality judgment circuits by comparison of the output signals of the first and second abnormality judgment circuits.

3. The controller of the in-vehicle device according to claim 2 ,
wherein the ECU comprises an alternative signal receiver that receives an alternative signal usable as an alternative to the first and second operating condition detection signals; and
wherein, when the redundancy monitoring circuit judges that an absolute difference between the output signals of the first and second abnormality judgment circuits is greater than or equal to a predetermined value, the actuator control circuit calculates and outputs the drive control signal in accordance with the alternative signal.

4. The controller of the in-vehicle device according to claim 2 ,
wherein, when the signal abnormality detection circuit judges that the abnormality data is contained in one of the output signals of the first and second abnormality judgment circuits, the actuator control circuit calculates and outputs the drive control signal in accordance with the other of the output signals of the first and second abnormality judgment circuits such that an output of the drive control signal becomes smaller than when no abnormality data is contained in the output signals of the first and second abnormality judgment circuits.

5. The controller of the in-vehicle device according to claim 1 ,
wherein each of the output signals of the first and second abnormality judgment circuits is in the form of a serial data signal that contains a trigger pulse indicating a start of signal transmission, an end pulse indicating an end of signal transmission and predetermined data provided between the trigger pulse and the end pulse and indicating the vehicle operating condition; and
wherein the signal abnormality detection circuit detects the abnormality in the output signal of the first or second abnormality judgment circuit when the predetermined data is missing or is out of sequence in the output signal of the first or second abnormality judgment circuit.

6. A power steering device, comprising:
a steering system that steers steerable wheels in response to steering operation of a steering wheel;
an electric motor that applies a steering force to the steering system;
a steering condition detection system that detects a steering condition and outputs first and second steering condition detection signals, said first and second steering condition detection signals being detected by and outputted from a plurality of respective detection elements or being detected by a common detection element and outputted through respective different electronic circuits;
a first abnormality judgment circuit that judges the presence or absence of an abnormality in the first steering condition detection signal and, upon detection of an abnormality in the first steering condition detection signal, outputs the first steering condition detection signal with abnormality data contained therein as an output signal;
a second abnormality judgment circuit that detects the presence or absence of an abnormality in the second steering condition detection signal and, upon detection of the abnormality in the second steering condition detection signal, outputs the second steering condition detection signal with abnormality data contained therein as an output signal;
an ECU having a microprocessor that performs drive control of the electric motor;
a signal abnormality detection circuit arranged in the ECU such that the signal abnormality detection circuit receives the output signals of the first and second abnormality judgment circuits and detects the presence or absence of an abnormality in the respective output signals of the first and second abnormality judgment circuits; and
a motor control circuit arranged in the ECU such that, when the signal abnormality detection circuit judges that no abnormality data is contained in the output signals of the first and second abnormality judgment circuits, the actuator control circuit calculates and outputs a drive control signal for drive control of the electric motor in accordance with at least one of the output signals of the first and second abnormality judgment circuits and such that, when the signal abnormality detection circuit judges that the abnormality data is contained in one of the output signals of the first and second abnormality judgment circuits, the actuator control circuit calculates and outputs the drive control signal in accordance with the other of the output signals of the first and second abnormality judgment circuits.

7. The power steering device according to claim 6 , further comprising a redundancy monitoring circuit arranged in the ECU so as to judge the presence or absence of the abnormality in the respective output signals of the first and second abnormality judgment circuits by comparison of the output signals of the first and second abnormality judgment circuits.

8. The power steering device according to claim 7 ,
wherein the ECU comprises an alternative signal receiver that receives an alternative signal usable as an alternative to the first and second s

Assignees

• Hitachi Automotive Systems Ltd
• Hitachi Automotives Systems Ltd

Inventors

• Sasaki Mitsuo
• Hisazumi Takumi

Classifications

• B62D6/10

  characterised by means for sensing {or determining} torque · CPC title

• B62D6/002

  computing target steering angles for front or rear wheels (B62D7/159 takes precedence) · CPC title

• B62D5/0484

  for reaction to failures, e.g. limp home · CPC title

• B62D5/046

  Controlling the motor · CPC title

• B62D5/0493 Primary

  detecting processor errors, e.g. plausibility of steering direction · CPC title