Vehicle multi-processor control system and method with processing load optimization

• US 5,544,054 A
• Filed: 10/31/1995
• Issued: 08/06/1996
• Est. Priority Date: 06/22/1993
• Status: Expired due to Term

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Minowa, Toshimichi, Morinaga, Shigeki, Ishii, Junichi, Kayano, Mitsuo
• Primary Examiner(s): ZANELLI, MICHAEL J
• Application Number:
  US08/550,876
• Time in Patent Office: 280 Days
• Field of Search: 395/200.03, 395/650, 364/424.01, 364/131, 364/133, 364/431.01, 364/431.04, 364/431.11, 364/431.12
• US Class Current: 701/1
• CPC Class Codes: B60R 16/0315 using multiplexing techniques multiplexing for transmission of signals G08C15/00; multiplexing for electrical communication in general H04J
• CPC Class Codes: B60W 10/06 including control of combustion engines
• CPC Class Codes: B60W 10/10 including control of change-speed gearings
• CPC Class Codes: B60W 10/18 including control of braking systems
• CPC Class Codes: B60W 50/06 Improving the dynamic response of the control system, e.g. improving the speed of regulation or avoiding hunting or overshoot
• CPC Class Codes: F02D 2250/12 Timing of calculation, i.e. specific timing aspects when calculation or updating of engine parameter is performed
• CPC Class Codes: F02D 41/266 the computer being backed-up or assisted by another circuit, e.g. analogue
• CPC Class Codes: G05B 15/02 electric
• CPC Class Codes: G06F 9/505 considering the load

Abstract

An automatic control system comprises a plurality of control processors which are connected by such transmission devices as LAN, BUS and so on. Control processing load to be executed by each of the control processors are detected and each control processor executes necessary and minimum control tasks corresponding to running state information on an automobile and carries on another control tasks in the remaining time based on the detected load of each control processor so as to smooth loads of the control processors.

Claims

1. An automobile control method for controlling each part of an automobile using a plurality of control units, which are connected by transmission lines with each other, including computers and memories, comprising the step of:

executing at least one of a plurality of control task programs stored in ones of said plurality of control units for controlling each part of the automobile, by at least one other of said plurality of control units having a lower processing load;

wherein at least one of said plurality of control units having said lower processing load judges its having said lower processing load upon receiving information on running state changes of said automobile external to said plurality of control units, reads out at least one of said plurality of control task programs stored in other of said plurality of control units, and executes said at least one control task program.

2. An automobile control system for controlling each part of an automobile, comprising:

plural control units connected by transmission lines with each other, each control unit including a computer;

a memory provided in at least one of said plural control units having a lower control processing load than other of said plural control units, said memory memorizing at least one of a plurality of control task programs stored in said other control units which is transferred to said memory via said transmission lines;

means in each control unit for judging, upon receiving information on running state changes of said automobile external to said plurality of control units, when said at least one of said plural control units has said lower control processing load.

3. An automobile control system according to claim 2, wherein said memory is an electrically rewritable memory, said electrically rewritable memory memorizing at least one of the plurality of control task programs stored in other of said plural control units having a high control processing load.

4. An automobile control system according to claim 2, wherein said memory is a rewritable memory.

5. An automobile control system according to claim 2, wherein said plural control units are of a same type;

and

wherein an address in said memory to which at least one of said plurality of control task programs is transferred being a same address in another memory of at least one of said other control units from which at least one of said plurality of control task programs is transferred.

6. An automobile control system according to claim 2, wherein said plural control units are of different types;

and

wherein at least one of said control task programs is transferred in a source program form of C language, compiled by a C compiler and stored in said memory.