Method and apparatus for short fault isolation in a controller area network

• US 9,678,131 B2
• Filed: 05/22/2015
• Issued: 06/13/2017
• Est. Priority Date: 05/27/2014
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations LLC (General Motors Company)
• Inventors: Jiang, Shengbing, Du, Xinyu, Nagose, Atul
• Primary Examiner(s): Assouad, Patrick
• Assistant Examiner(s): Pretlow, Demetrius
• Application Number:
  US14/720,414
• Publication Number:
  US 20150346260A1
• Time in Patent Office: 753 Days
• Field of Search: 324500, 324509, 324512, 324537, 324538, 324555, 32475601, 32475605, 361 42, 361 54, 439 34, 439251, 439921, 439949, 702 1, 702 57, 702 58, 702 59
• CPC Class Codes: G01R 31/006 on road vehicles, e.g. automobiles or trucks testing of ignition installations peculiar to internal combustion engines F02P17/00
• CPC Class Codes: G01R 31/50 Testing of electric apparatus, lines, cables or components for short-circuits, continuity, leakage current or incorrect line connections testing of sparking plugs H01T13/58
• CPC Class Codes: G06F 11/0739 in a data processing system embedded in automotive or aircraft systems
• CPC Class Codes: G06F 11/0793 Remedial or corrective actions recovery from an exception in an instruction pipeline G06F9/3861; by retry G06F11/1402; for recovering from a failure of a protocol instance or entity H04L69/40
• CPC Class Codes: G06F 11/3013 where the computing system is an embedded system, i.e. a combination of hardware and software dedicated to perform a certain function in mobile devices, printers, automotive or aircraft systems testing or monitoring of control systems or parts thereof G05B23/02
• CPC Class Codes: G06F 11/349 for interfaces, buses

Abstract

A controller area network (CAN) includes a CAN bus having a CAN-H wire, a CAN-L wire, and a pair of CAN bus terminators located at opposite ends of the CAN bus. The CAN further includes a plurality of nodes including controllers wherein at least one of the controllers is a monitoring controller. The monitoring controller includes a detection control routine for isolating faults on the CAN bus including measuring a CAN-H wire voltage, measuring a CAN-L wire voltage, and isolating a short fault based upon the CAN-H wire voltage and the CAN-L wire voltage.

Claims

1. A controller area network (CAN) comprising:

a CAN bus including a CAN-H wire and a CAN-L wire;

a pair of CAN bus terminators located at opposite ends of the CAN bus, each terminator having a corresponding known terminator resistance value;

a plurality of nodes including controllers wherein at least one of said controllers comprises a monitoring controller; and

said monitoring controller comprising a detection control routine for identifying fault-types on the CAN bus, comprising the following steps;

determining a set of CAN bus parameters; and

identifying fault-types based upon the CAN bus parameters;

wherein said set of CAN bus parameters comprises a CAN-H wire voltage and a CAN-L wire voltage, and said fault-types comprise CAN bus short faults; and

wherein the step of identifying fault-types based upon the CAN bus parameters comprises the following steps;

comparing the CAN-H wire voltage, the CAN-L wire voltage and a voltage differential between the CAN-H wire voltage and the CAN-L wire voltage to a predetermined set of criteria defining a plurality of fault signatures corresponding to respective fault-types;

identifying fault-types when said comparison matches one of the fault signatures.

3. The controller area network (CAN) of claim 1, wherein the step of determining a set of CAN bus parameters comprises the following step:

sampling a predetermined number of data points comprising a respective CAN-H wire voltage and a respective CAN-L wire voltage.

5. The controller area network (CAN) of claim 3, wherein said predetermined number of data points is inversely proportional to a CAN bus load.

2. A controller area network (CAN) comprising:

a CAN bus including a CAN-H wire and a CAN-L wire;

a pair of CAN bus terminators located at opposite ends of the CAN bus, each terminator having a corresponding known terminator resistance value;

a plurality of nodes including controllers wherein at least one of said controllers comprises a monitoring controller; and

said monitoring controller comprising a detection control routine for identifying fault-types on the CAN bus, comprising the following steps;

determining a set of CAN bus parameters; and

identifying fault-types based upon the CAN bus parameters;

wherein said set of CAN bus parameters comprises a CAN-H wire voltage and a CAN-L wire voltage, and said fault-types comprise CAN bus short faults; and

wherein the steps of determining a set of CAN bus parameters comprises taking a predetermined number of measurements of the CAN-H wire voltage and the CAN-L wire voltage; and

wherein the step of identifying fault-types based upon the CAN bus parameters comprises;

providing each measurement of CAN-H wire voltage and the CAN-L wire voltage to a predetermined fault signature matrix comprising a set of predetermined tests and predetermined combinations of said tests comprising respective CAN bus fault signatures;

for each test, counting a respective number of tests passed;

for each CAN bus fault signature, evaluating the number of tests passed for each test against a respective predetermined count correspondence threshold; and

outputting from said matrix an identification of a fault-type corresponding to any evaluation where each count correspondence threshold is attained for every relevant test.

4. A controller area network (CAN) comprising:

a CAN bus including a CAN-H wire and a CAN-L wire;

a pair of CAN bus terminators located at opposite ends of the CAN bus, each terminator having a corresponding known terminator resistance value;

a plurality of nodes including controllers wherein at least one of said controllers comprises a monitoring controller; and

said monitoring controller comprising a detection control routine for identifying fault-types on the CAN bus, comprising the following steps;

determining a set of CAN bus parameters; and

identifying fault-types based upon the CAN bus parameters;

wherein said set of CAN bus parameters comprises a CAN-H wire voltage and a CAN-L wire voltage, and said fault-types comprise CAN bus short faults;

wherein the step of determining a set of CAN bus parameters comprises the following step;

sampling a predetermined number of data points comprising a respective CAN-H wire voltage and a respective CAN-L wire voltage; and

wherein the step of identifying fault-types based upon the CAN bus parameters comprises the following steps;

subjecting the data points to a set of pass/fail tests;

for each test, producing a pass count;

for each fault-type, evaluating the pass counts against respective count requirements; and

identifying the fault-type when all respective count requirements corresponding to the fault-type are satisfied.

6. The controller area network (CAN) of claim 4, wherein said predetermined number of data points is inversely proportional to a CAN bus load.

7. A controller area network (CAN) comprising:

a CAN bus including a CAN-H wire and a CAN-L wire;

a pair of CAN bus terminators located at opposite ends of the CAN bus, each terminator having a corresponding known terminator resistance value;

a plurality of nodes including controllers wherein at least one of said controllers comprises a monitoring controller; and

said monitoring controller comprising a control routine for identifying a plurality of fault-types on the CAN bus, comprising the following steps;

sampling a predetermined number of data points comprising a respective CAN-H wire voltage and a respective CAN-L wire voltage;

subjecting the data points to a set of pass/fail tests;

for each test, producing a pass count;

for each fault-type, evaluating the pass counts against respective count requirements; and

identifying the fault-type when all respective count requirements corresponding to the fault-type are satisfied.

8. The controller area network (CAN) of claim 7, wherein said predetermined number of data points is inversely proportional to a CAN bus load.

9. A controller area network (CAN) comprising:

a CAN bus including a CAN-H wire and a CAN-L wire;

a pair of CAN bus terminators located at opposite ends of the CAN bus, each terminator having a corresponding known terminator resistance value;

a plurality of nodes including controllers wherein at least one of said controllers comprises a monitoring controller; and

said monitoring controller comprising a control routine for identifying a plurality of fault-types on the CAN bus, comprising the following steps;

sampling a predetermined number of data points comprising predetermined CAN bus parameters;

subjecting the data points to a set of pass/fail tests;

for each test, producing a pass count;

for each fault-type, evaluating the pass counts against respective count requirements; and

identifying the fault-type when all respective count requirements corresponding to the fault-type are satisfied.

10. The controller area network (CAN) of claim 9, wherein said predetermined CAN bus parameters comprise a CAN-H wire voltage, a CAN-L wire voltage and CAN bus resistance, and wherein said fault-types comprise CAN bus short faults and CAN bus open faults.

11. The controller area network (CAN) of claim 9, wherein said predetermined CAN bus parameters comprise a CAN-H wire voltage and a CAN-L wire voltage, and wherein said fault-types comprise CAN bus short faults.

12. The controller area network (CAN) of claim 9, wherein the said predetermined number of data points is inversely proportional to a CAN bus load.