Research Methodology for the Test Automation of Truck Controller Software System

Mr.Ajay Palkar ,Ms.Priya Deshpande Abstract. The new generations of Commercial Vehicles have seen an exponential development in on-board electronic systems, which control increasingly broad parts of the functionality. The vehicle manufacturers need to calibrate their methods and tools to handle the increasing complexity. Body controller module provides flexible on-vehicle integration capability. The electrical system in the vehicle is mostly concerned with lights, starter motors, windshield wipers, and many of such components & systems. Body controller plays vital role integrating all such devices and enhance functional data flow effectively. As a complex and configurable software/hardware device of the vehicle system, the body controller requires effective validation. These applications are repetitive as well as time consuming hence needs to be automated. In order to overcome these disadvantages a cost effective automated testing is required. This paper proposes thei implementation aspects of a reliable and accurate LabVIEW-based automated testing system. The proposed system permits the testing to be performed efficiently and without intervention. Most importantly, it relieves the operator of the usual responsibility for manually controlling the system for the test. Virtual instrumentation technique and PXI architecture is used which enhances the productivity, performance and reduces the cost through easy-to integrate LabVIEW-based application software and PXI modular hardware. Keywords: Automated Testing, Body controller, Virtual Instrumentation, PXI architecture, LabVIEW

1. Introduction

1.1. Introduction This paper proposes an Automated Test System (ATE) designed using virtual instrumentation, focusing

functional complexity, cost, modularity, scalability. The proposed system is chosen after complete study & comparison between various test systems available in the market. The most applicable system being VXI based, operates with the help of the software, a VC++ based software system. The goal of this system is to provide a means to test the various vehicle modules alone and in combination with each other. This testing can be done using the following procedure

For Functional/Integration testing of a feature, they select applicable signal input from test bench. These signals are associated with Indicators, switches on the test bench depending on the feature. For the feature under test, possible test cases are prepared. As per the test case, inputs are given through switch pack, digital switches or potentiometers. The result or expected output can be a change in value of a signal, message, alarm or lamp indicator, whatever is mentioned in STD, STP document.

1.2. Disadvantages of conventional system - Unreliable system: possibility of human errors - Complex to understand and use - Foolproof testing cannot be achieved - Loss of man-hours as the testing is manual

Paper submitted on:Fri, Feb 25, 2011 at 10:15 AM Mr. Ajay Palkar Head – Electrical & Electronic Systems Mahindra Engineering Services Ltd. Cell: +91 9766623136 palkar.ajay@mahindraengg.com Ms. Priya R. Deshpande Lecturer -MITCOE PUNE Cell: 9028306792 priyardeshpande@gmail.com

104

2011 International Conference on Environmental and Computer Science IPCBEE vol.19(2011) © (2011) IACSIT Press, Singapore

- No report generation is available - Regression and Integration testing is difficult in the present environment. - Hardware Limitations - An automated test system is proposed in this document to overcome all these disadvantages. Proposed

system will have the following advantages over the conventional test system.

1.3. Advantages of proposed system - Achievement of higher reliability and quality testing standards - Reduction in cost and time of testing could be achieved - Increases test system flexibility deployable to a variety of applications - High performance architecture that significantly increases test system throughput and provides tight co-

relation and integration of instruments from multiple suppliers including high-speed analog and digital systems

- Increases test system longevity based on widely adopted industry standards that enable technology upgrades to improve performance and meet future test requirements

- Test person would not be blocked and the reports generated would give a clear scene of testing accomplished in his absence

- Pre-knowledge of test setup and testing experience will not play a greater role in achieving correct results

2. PROPOSED SYSTEM

2.1. Problem Definition This project proposes a virtual instrumentation based automated test system (ATE), based on comparison

of technical specifications, cost, complexity, modularity, scalability and support of different available instrumentation options available in the market. Test system should give options for manual, semi-automatic and automatic testing

2.2. Features of Proposed System 1. Higher reliability and quality testing standards can be achieved. 2. Reduction in cost and time of testing could be achieved. 3. Increases test system flexibility deployable to a variety of applications. 4. It provides High performance architecture that significantly increases test system throughput. It

provides tight co-relation and integration of instruments from multiple suppliers including high-speed analog and digital systems.

5. Increases test system longevity based on widely adopted industry standards that enable technology upgrades to improve performance and meet future test requirements.

6. Test person would not be blocked and the reports generated would give a clear scene of testing accomplished in his absence.

7. Pre-knowledge of test setup and testing experience will not play a greater role in achieving correct results.

2.3. Research Methodology The scope of this system is to facilitate the automated execution of test, based on the test scripts prepared

through LabView. This system is intended for regression and integration testing of the Body Control and allied modules.

Development team will have the unit testing or bench testing will be done using test bench. Integration and regression testing will be carried out on the test automation system. Feature development team will use present test bench for unit testing. Feature development team can have the option of using test automation

105

system to carry out more detailed test, in case it is needed. Test Strategy Development and Testing Execution Team will develop the strategy for testing the features, Prepare test plans accordingly, and development of test script and software test descriptions (STDs). Test Execution Team will execute the tests as per test strategies and test plans practically.

Basic functionality testing check the different configurations that have been affected, check the functionality of a feature, Regression testing, Analysis or generation of test report as applicable. Test Environment:

The test system is based on the client sever topology. The PXI hardware is installed on the server side, which communicates with the host sever through Ethernet link. The host server has the LabView application running on it. This application controls the execution of different input and output signals to the body control module. The application also has web-server interface module, which communicates with the client system. The web server is integrated with the LabView, thus gives the direct integration of test application and the web interface. Some database management system (either Ms-Access or Oracle) needs to be installed to handle the different databases.

3. SOFTWARE DESIGN

3.1. Architecture Diagram: Test system architecture has been defined in this section. To maximize the flexibility and performance of

the hardware and software, we have used layered system architecture. This system architecture provides additional abstraction with each layer making the system upgrades and equipment reuse easier. The system architecture shown below starts from the device layer where the engineer selects specific I/O to meet requirements and then builds on each layer up to the optional Test Management layer.[11]

Figure 1: Test System Architecture [14]

Following advantages are envisaged out of the use of this system architecture definition: 1. It defines overall test process, execution flow, and operator control 2. Platform Independence 3. It focuses on building a modular test software framework rather than a product specific application 4. Large board area in small package 5. It integrates with external systems 6. It lowers development and maintenance costs 7. Increases system flexibility and extensibility 8. It extends useful test system life 9. Vendor independent as there is option of different vendors at different layers

106

10. It takes advantage of existing commercial off-the-shelf (COTS) test management software architecture

11. Could be accessed remotely Following are the different modules of proposed system: a. Generation of DATA files b. Create Software Test Documentation for particular feature c. Development of Virtual Instrumentation. d. Testing of Feature e. Report generation. a. Generation of DATA files

DATA DATA is a Vehicle System Abstract data, which is a XML file .The Test System shall take .XML

(DATA) file as an input for customizing the GUI and loading the configuration file into the Body Control Module.

The process of DATA generation is as follows. Vehicle Orders When ordering a vehicle, customers select a series of sales feature codes available for their model. This

collection of sales feature codes is called a vehicle order. Configurable software architecture is necessary as a result of variations in vehicle orders. CP

Once the vehicle order is generated, the Configuration Platform (CP) uses it to determine the parts and subassemblies necessary to construct the vehicle. One key part, relative to software, is the Electrical System Controller (ESC). The ESC interfaces with networked modules and discrete devices in the vehicle. CP also generates a list of computer software units.[10]

Proprietary Software Proprietary Software uses the list of computer software units to generate a Data. Proprietary Software

then converts the DATA into a set of configuration data structures, a binary configuration. Operating Program

Requirement configuration of DATA can be changed. In this way the DATA file is generated. Create Software Test Documentation for particular feature : The tests contained in this document have been created under the following guidelines: Completely test the feature’s requirements as specified in its requirements document(s) e.g. SRD,

SSSS, etc. Provide a single document for specifying tests that can be run on test automation software. Provide a framework that can be modified on a test by test basis to best obtain the above goals. Subsystem Segment Specification (SSSS) for feature This SSSS captures the requirements that pertain to

the system feature and translates those requirements into a Systems Design. c. Development of Virtual Instrumentation LabView is used to provide virtual instrumentation for the test automation. All the features can be tested

with the help of Automation Test System which is developed with the help of LabView. The input file DATA is loaded in controller and according to STD that particular feature will be tested. For backend

Microsoft Access is used to create database which will be used to store client request and test script results. d. Testing of Feature With the help of STD the feature will be tested and results will be stored in database. e. Report generation

107

Reports will be automatically generated in test automation software, and Analysis of the result can be done.

4. USE CASE DIAGRAM

Figure 2: System Use Case Diagram Sequence Diagram

Figure 3: Sequence diagram for connecting to the system

5. TESTING

5.1. Vehicle Validation Testing IEEE Defines it as “The process of testing an integrated hardware and software system to verify that the

system meets its specified requirements”. It is tested against system-required specifications. In System Testing, the real data is used and sometimes user’s participation is used. In this testing unit under test (UUT) is placed on the actual vehicle and real data is providing to unit. The actual functionality of the UUT is tested at this level. Currently, this testing is performed by putting the UUT to the actual vehicle.

6. EXPERIMENTATION AND RESULTS Experimentation and Result and discussion In Experimentation results are calculated with conventional system and proposed system. Following are

the results of proposed system. 1. Overall testing time to test the feature for conventional system and proposed system.

108

Figure 4: Analysis of overall testing time for feature

As a result if we will see there is a major difference in time to test feature. Time required for proposed

system is very less than conventional system. so proposed system increases performance of system. 2. Body controller response time for conventional system and proposed system

Figure 5: Analysis of Body controller response

As a result if we will see there is a major difference in response time of body controller for proposed system and conventional system. Body controller response time is very less for the proposed system.

3. Overall percentage CPU utilization

Figure 6: Analysis of CPU utilization

As a result if we will see there is a major difference in percentage CPU utilization for test system. CPU

utilization for proposed system is very less than conventional system. As processor utilization is less it increases performance of system. 4. Comparative study of PXI, VXI, LXI technologies.

Figure 7: Comparative study of PXI, VXI, LXI technologies.

109

7. CONCLUSION AND FUTURE SCOPE Vehicle manufacturing industry uses body controller to integrate on-vehicle systems, which requires

extensive testing. Currently they are using a manual Test bench for the testing of Body Controller ECU. As this conventional system are having many disadvantages, to overcome these disadvantages the proposed research work to develop test automaton strategy will be developed. Which will have higher reliability and quality testing .And also reduction in cost and time of testing could be achieved. This will increases test system flexibility deployable to a variety of applications. This proposed system will enhance the performance of system and also this system will be reliable and scalable than the existing system.

As a result of experimentation body controller response time for proposed system is very less as compared to existing system. CPU utilization is also very less and performance time to test any feature is very less in proposed system. With the help of proposed system we can have the analysis of different configuration files for particular feature. In

this way we can achieve high performance, reliability and scalability from the proposed system. Future scope for this project is that we can use National Instruments NI TestStand .NI TestStand is used for the test script preparation. NI TestStand is ready-to-run test management software designed to help you develop automated test and validation systems faster. NI TestStand can be use to develop, execute, and deploy test system software. With NI TestStand, you can develop test sequences that integrate code modules written in any test programming language. Sequences also specify execution flow, reporting, database logging, and connectivity to other enterprise systems.

8. REFERENCES Technical Paper References: [1] Grant Drenkow, Agilent Technologies “Future Test System Architectures” IEEE A&E SYSTEMS MAGAZINE

MAY 2005

[2] Chaturi Singh and K. Poddar “Implementation of a LabVIEW-Based Automated

Wind Tunnel Instrumentation System”, National Wind Tunnel Facility Indian Institute of Technology Kanpur (INDIA), 978-1-4244-2746-8/08/$25.00@2008 IEEE

[3] Yanxia Liu, BeiJing, China ,“Application of can-bus in embedded vehicle body control system”, 978-0-7695-3679-8/09 $25.00 © 2009 IEEE

[4] Chaturi Singh and K. Poddar “Implementation of a VI-Based Multi-Axis Motion Control System for Automated Test and Measurement Applications” National Wind Tunnel Facility Indian Institute of Technology Kanpur (INDIA)

[5] Xu-lan He, “Embedded Systems Based Modular Test Automation”, 2009 ISECS International Colloquium on Computing, Communication, Control, and Management

[6] Eric A. Bingham , “Automated Testing Using PX1 and IVI Technologies” , 0-7803-8449-0/04/$20.00 02004 lEEE

[7] Martino Fomasa, Massimo Maresca, Nicola Zingirian “Development of a Service-Oriented Architecture for the dynamic integration of mobile remote software components” 0-7803-9402-X/05/$20.00 © 2005 IEEE,VOLUME 1

Book References: [8] Grady Booch “Unified Modeling Language “

[9] Roger S. Pressman “A Practitioner’s Approach to Software Engineering Practices” Online References: [10] PXI Based Flight-Line Test Sets-https://www.geotestinc.com/KnowledgeBase/KBArt icle.aspx?ID=177

[11] LabVIEW Manual-http://www.ni.com/LabVIEW/ http://sine.ni.com/nips/cds/view/p/lang/en/nid/13800

[12] Information on NI developer Zone, www.zone.ni.com

[13] Product catalogs from www.etas.com and www.dspaceinc.com

[14] Articles, presentations and product catalog provided by VXI Tech. Inc., www.vxitech.com

110

[15] LabView Manuals http://www.morechemistry.com/labview/ Author Information:

1. Mr. Ajay Palkar

Head – Electrical & Electronic Systems Mahindra Engineering Services Ltd. Cell: +91 9766623136 palkar.ajay@mahindraengg.com

2. Ms.Priya R.Deshpande

Assistant Professor -MITCOE PUNE Cell: 9028306792 priyardeshpande@gmail.com

111