Engine control-oriented worst execution analysis method

Abstract

The invention discloses an engine control-oriented worst execution analysis method, which comprises the following steps of: determining a processor model according to requirements of an engine control system, and selecting a static model and a worst execution time analysis tool corresponding to the processor model; analyzing the software architecture, confirming a task scheduling mode and a task time distribution scheme, and identifying the influence of the software architecture on the worst execution time; identifying target machine environment factors including internal hardware configuration and external hardware configuration of the processor, and compiling link parameters; based on an identification result, configuring target machine environment parameters in the worst execution time analysis tool, and importing a target code of to-be-analyzed software; in combination with an engine control function and an application scene, identifying a worst call tree path through static analysis, performing actual test on the final worst scene in a software and hardware integration test environment, and verifying whether the final worst scene meets time performance requirements and task time distribution in software requirements or not; if not, iteratively adjusting the software architecture or demand and then repeatedly executing the steps; the time security of the worst execution analysis result is confirmed through expert peer review, and it is ensured that all potential execution paths and extra time are covered; according to the method, the possible worst path can be identified more efficiently and accurately.

Description

Technical Field

[0001] The present invention relates to the technical field of aviation engines, and in particular to a worst-case execution analysis method for engine control. Background Art

[0002] As a highly reliable and secure real-time system, aircraft engine digital control systems have strict timing requirements. In such systems, software correctness depends not only on functional correctness but also on meeting strict timing constraints. Worst-case execution analysis, which aims to determine the maximum execution time within a functional scope, is a common method for verifying software's timing safety. DO-178C is the airworthiness standard for the development of airborne software in civil aviation. Objectives A-5.6 and A-6.5 of this standard clearly define worst-case execution time analysis for airborne software, but lack guidance on specific worst-case execution time analysis methods. Currently, there is no specific guidance on how to conduct worst-case execution analysis for engine control software that meets DO-178C requirements, leading to numerous difficulties in engineering implementation. Summary of the Invention

[0003] Purpose of the invention: The purpose of the present invention is to provide a worst-case execution analysis method for engine control. By identifying and analyzing the hardware characteristics, software architecture, and target machine environmental factors of the controller, a worst-case execution time analysis method based on static analysis is proposed. The worst-case execution time analysis method in DO-178C is further refined and clarified to support the achievement of the worst-case execution time analysis goals in DO-178C.

[0004] Technical solution: The worst-case execution analysis method for engine control according to the present invention comprises the following steps: S1: Determine a processor model according to engine control system requirements, and select a static model and worst-case execution time analysis tool corresponding to the processor model; S2: Analyze the software architecture, confirm the task scheduling method and task time allocation plan, and identify the impact of the software architecture on the worst-case execution time; S3: Identify the target machine's environmental factors, including the processor's internal and external hardware configurations, as well as compilation and linking parameters; S4: Based on the identification result of S3, configure the target machine environment parameters in the worst execution time analysis tool and import the target code of the software to be analyzed; S5: Combine engine control functions and application scenarios to identify the worst-case call tree path through static analysis, including loop count and control flow analysis. Establish a preliminary worst-case scenario and iterate to verify its rationality until the final worst-case scenario is determined. S6: Perform actual testing on the final worst-case scenario in a software and hardware integration test environment to verify whether it meets the time performance requirements and task time allocation in the software requirements; if not, iteratively adjust the software architecture or requirements and repeat S2 to S5; S7: Confirm the time safety of the worst-case execution analysis results through expert peer review to ensure that all potential execution paths and additional time are covered.

[0005] Furthermore, in step S1, the processor models include MPC5554 and MPC5674 series processors, and the corresponding CPU static model is selected according to the project hardware requirements.

[0006] Furthermore, the task scheduling methods in step S2 include Earliest Deadline First (EDF) and Rate Monotonic Scheduling (RMS).

[0007] Furthermore, in step S3, the internal hardware configuration of the processor includes internal RAM, internal FLASH, Cache, Pipeline, etc., and the external hardware configuration includes external RAM, external FLASH, etc.

[0008] Furthermore, in step S5, the control flow analysis includes analysis of valid / invalid control scenarios and analysis of the consistency between the number of cycles and the actual situation of the project.

[0009] Furthermore, in step S6, the actual test includes repeatedly executing the worst-case scenario multiple times in the target machine environment, and recording the maximum value of the actual execution time, and comparing it with the static analysis result for verification.

[0010] Furthermore, in step S7, the expert peer review includes a review of the analysis tool configuration parameters, control flow path coverage completeness, and test result consistency.

[0011] Beneficial effects: Compared with the existing technology, the present invention has the following significant advantages: the worst-case execution analysis method proposed in the present invention is based on the processor static model for analysis, which can fully consider the impact of processor hardware characteristics that cannot be manually identified, thereby obtaining more accurate worst-case execution analysis results; the worst-case execution analysis method proposed in the present invention is based on the static analysis method, and the program target code performs control flow and other analyses, which can more efficiently and accurately identify possible worst-case paths and reduce the development cost of engine control system software. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a flow chart of the present invention. DETAILED DESCRIPTION

[0013] The technical solution of the present invention will be further described below with reference to the accompanying drawings.

[0014] like Figure 1 As shown, an embodiment of the present invention provides a worst-case execution analysis method for engine control, comprising the following steps: (1) According to the requirements of the engine control system, the processor type and compiler type to be used are clearly defined, so as to select the applicable processor static model and worst-case execution auxiliary tool; (2) Analyze the engine control system software architecture, identify the task scheduling method and task time allocation, and determine the analysis entry point and analysis strategy; (3) Identify the target machine's environmental factors and set them in the worst-case execution assistance tool, including internal and external hardware configurations such as chip type and frequency; (4) Starting from the analysis entry, use the worst-case execution auxiliary tool to iteratively search for the worst-case path until a reasonable worst-case path is found; (5) Conduct actual testing and confirmation in the software and hardware integration test environment to obtain the final worst-case execution analysis results, and confirm that the worst-case execution analysis results meet the time performance requirements in the software requirements and the task time allocation in the software architecture; (6) Conduct expert peer review of the software worst-case execution analysis method and results to confirm that the analysis results meet the time performance requirements in the software requirements and the task time allocation in the software architecture, and that all potential execution paths and additional time have been considered, which means that the time safety of the software can be met and the worst-case execution analysis activity for engine control is completed.

Claims

1. A worst-case performance analysis method for engine control, characterized in that: The following steps are involved: S1: Determine a processor model according to engine control system requirements, and select a static model and worst-case execution time analysis tool corresponding to the processor model; S2: Analyze the software architecture, confirm the task scheduling method and task time allocation plan, and identify the impact of the software architecture on the worst-case execution time; S3: Identify the target machine's environmental factors, including the processor's internal and external hardware configurations, as well as compilation and linking parameters; S4: Based on the identification result of S3, configure the target machine environment parameters in the worst execution time analysis tool and import the target code of the software to be analyzed; S5: Combine engine control functions and application scenarios to identify the worst-case call tree path through static analysis, including loop count and control flow analysis. Establish a preliminary worst-case scenario and iterate to verify its rationality until the final worst-case scenario is determined. S6: Perform actual testing on the final worst-case scenario in a software and hardware integration test environment to verify whether it meets the time performance requirements and task time allocation in the software requirements; if not, iteratively adjust the software architecture or requirements and repeat S2 to S5; S7: Confirm the time safety of the worst-case execution analysis results through expert peer review to ensure that all potential execution paths and additional time are covered.

2. The worst-case execution analysis method for engine control according to claim 1, characterized in that: In step S1, the processor models include MPC5554 and MPC5674 series processors, and the corresponding CPU static model is selected according to the project hardware requirements.

3. The worst-case performance analysis method for engine control according to claim 1, characterized in that: The task scheduling methods in step S2 include earliest deadline first and rate monotonic scheduling.

4. The worst-case performance analysis method for engine control according to claim 1, characterized in that: In step S3, the internal hardware configuration of the processor includes internal RAM, internal FLASH, Cache, Pipeline, etc., and the external hardware configuration includes external RAM and external FLASH.

5. The worst-case execution analysis method for engine control according to claim 1, characterized in that: In step S5, the control flow analysis includes analysis of valid / invalid control scenarios and analysis of the consistency between the number of cycles and the actual project situation.

6. The worst-case execution analysis method for engine control according to claim 1, characterized in that: In step S6, the actual test includes repeatedly executing the worst-case scenario in the target machine environment multiple times, and recording the maximum value of the actual execution time, and comparing it with the static analysis result for verification.

7. The worst-case execution analysis method for engine control according to claim 1, characterized in that: In step S7, the expert peer review includes a review of the analysis tool configuration parameters, control flow path coverage completeness, and test result consistency.

8. An electronic device comprising a memory, a processor, and a computer program stored in the memory, characterized in that: When the processor executes the program, the steps of the method according to any one of claims 1 to 7 are implemented.

9. A computer-readable storage medium storing a computer program, characterized in that: When the program is executed by a processor, the steps of the method according to any one of claims 1 to 7 are implemented.

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