Building a system testing environment using the VT … Article Building a system testing environment using the VT system The need for system testing is on the rise with the increasing

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Building a system testing environment using the VT system

The need for system testing is on the rise with the increasing modularization of components in automobile development. Calsonic Kansei Corporation (Calsonic Kansei) introduced Vector’s ECU testing solution for meter control systems, succeeding in building a testing system environment.

Background of testing system introduction

Component modularization

The number of components a car is equipped with tends to increase to achieve multifunctionality in automobiles. Components thus need to be designed collectively as modules to reduce the number of individual components and achieve reduced weight and improved fuel efficiency with that. As one of the few suppliers that globally provide module systems, Calsonic Kansei provides products such as cockpit modules and front-end modules to OEMs. A cockpit module combines components such as the instrument panel, air conditioner unit, meters, airbag module, electronic control units (ECUs), audio system, wiring harness and steering column on a framework of the steering member.

According to Mr. Hisafumi Nishida of the Development Reliability Group at Calsonic Kansei’s Development Division, “The benefits of modularization extend to production as well as development. For example, the amount of labor required increases at an OEM assembly plant, the more components there are to equip the car with. Assembly work thus becomes more efficient by reducing the number of components through modularization.”

Importance of system testing

If components are modularized (systemized), some aspects are difficult to verify testing individual components in the development stage. Mr. Nishida states that, “cooperative control timing is a difficult aspect to verify without system testing. For example, each ECU starts up after application

www.vector-japan.co.jp February 2009

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Tested system (3 ECUs)

CANoe

Tested ECU 1

CAN

GPIB

Ethernet

CANcardXL

RS232C/USB

Diag on CAN

CANstressDR

VT system

CAN

CAN

Diag function

External power source

to supply power to ECU

Digital & analog I/O

ECU power supply line

Test Report

failed passed

Test definition

(XML)

Test definition(CAPL)

TAE (Test Automation Editor)

CAPL Editor

Test definition editor

Communications database

CANdb

Diagnosis database

CDD

CANoe testing functions GPIB

Ethernet

CANcardXL

RS232C/USB

CANdb++ Editor

CANdelaStudio

Database Editor

Database

● Automatic testing● Analysis info display at

testing● Automatic determination

of test results

of power at different timing, so one ECU may be in standby whereas another is not in standby yet. There is also a difference in interpretation of specifications. If the ECU sending a message and ECU receiving the message are of different specifications, the problem arises of the system as a whole having misinterpreted specifications even if the individual ECUs are compliant with specifications. For that reason, we need to confirm whether or not startup timing matches as a whole system and specifications are misinterpreted.” Calsonic Kansei had been using Vector’s CANoe development tool for vehicle networks in testing individual ECUs. If necessary, the individual ECUs were connected to each other after individual testing and system overall verification performed. Mr. Nishida says that, “We had felt the need for system testing in the past, but we were concerned that it would take tremendous manpower to build a system testing environment. So, we couldn’t seem to get around to starting that. In a long-term perspective, we decided building a system testing environment was necessary to continuously improve ECU testing technology and precision and to improve quality (both for ECUs and testing) rather than just simply increasing ECU testing efficiency.”

Solutions for system testing with Vector products

Building and automating a system testing environment with the VT system

Calsonic Kansei was initially aiming to build an environment where system tests could be carried out at any time. For that reason, it studied an environment where CANoe is used with ECUs always connected. Meanwhile, Vector comprehensively proposed an ECU testing solution other than just CANoe. That included the VT system hardware for I/O testing that can be linked to CANoe to simultaneously control CAN communication and digital/analog signals, Test Automation Editor (TAE) that can easily create test cases, the CANdela product family that make test creation more efficient and raise testing quality by making a database of diagnosis specs, and CANstressDR that can make diverse disturbance tests (Fig. 1, Fig. 2). Mr. Nishida states that, “We felt that introducing the VT system would allow us to achieve testing that was difficult to do manually. For example, switching on and off manually at intervals of 100, 200 or 300 milliseconds is extremely difficult. But we could control switching on and off automatically at even shorter cycles (in units of 10 milliseconds) using the VT system, thus improving testing precision.”

Fig. 1 Testing system hardware configuration

Fig. 2 Testing system software configuration


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Calsonic Kansei introduced a solution proposed by Vector for meter control system composed of the three ECUs for meters, air conditioners and electronic control units. Furthermore, Vector provided Calsonic Kansei with five typical test cases assuming diagnosis testing and I/O testing (Table 1).

No Type of test Test case Details of test Vector product function used

1

Diagnosis testing

Disturbance testing for overall CAN bus

• External power on/off, and output voltage control

• Disturbance testing for overall CAN bus

• Determining if ECU detects abnormality

• CANoe GPIB access function • VT1004 built-in relay• CANstressDR analog disturbance

function• CANoe diagnosis function • CANoe test function

2CAN stubline disturbance testing for ECUs


• CAN stubline disturbance testing for ECUs

• Determining if ECU detects abnormality

• CANoe GPIB access function • VT1004 built-in relay• Customize module for VT system*1

• CANoe diagnosis function • CANoe test function

*1 CAN stubline disturbance is planned to be supported by the standard module to be released later.

3

I/O testing

Switch simulation testing


• Simulation of switch input for ECUs

• CANoe GPIB access function • VT1004 built-in relay• VT2004 built-in relay• CANoe test function

4 Output testing


• Signal value in CAN message change

• CANoe GPIB access function • VT1004 built-in relay• CANoe test function• VT1004 PWM measurement function,

CANoe test function

5 Sensor simulation testing• External power on/off, and

output voltage control • Sensor input simulation

• CANoe GPIB access function • VT1004 built-in relay• VT2004 decade resistor• CANoe test function

Table 1. Five test cases provide by Vector


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These test case are defined in CAPL (C-like script language for CANoe) and XML for CANoe testing. Major test sequences in particular are defined in XML, so new test definition work and existing test definition expansion can be done easily with an intuitive GUI using drag and drop provided by the Test Automation Editor (TAE) XML editor for CANoe testing (Fig. 3).

Of the five test cases provided by Vector, Calsonic Kansei started expansion for the diagnosis test case. As Mr. Nishida puts it, “The reason we started with a diagnosis-related test case was that diagnosis testing was highly general, being required for all ECUs. In the future, we would like to use the remaining test cases and start work on automation of I/O testing. Making use of the VT system, we can automate turning switches on and off that had been done manually, so we can expect a great reduction in labor.”

Use of diagnosis test base

Up to recently, Calsonic Kansei had managed in Excel items such as diagnosis requests, diagnosis responses, and diagnosis parameters for each ECU. Based on that, ECU diagnosis function analysis and testing was done by hand. But with the introduction of the test solution, management of such information by CANdela database (Vector’s diagnosis database) was introduced. The following benefits can be expected from that.

Fig. 3 Test Automation Editor (TAE)

• Simplification of test definition Using the CANdela database, diagnosis objects such as diagnosis requests, diagnosis responses and diagnosis parameters can be handled by identifier name. Also, input support functions such as drag and drop settings for diagnosis objects in TAE and selection from diagnosis object dialogs in CAPT editor can be used. That leads to increased efficiency by making test definition simple along with reducing careless mistakes.

• Handling ECU variants In cases such as ECUs being for delivery to different regions, minute differences may occur such as changed byte position of diagnosis parameters, even if ECUs have the same function. CANdela database manages such differences as “ECU variants (derived specs)”. Such differences can be absorbed by compiling using the diagnosis parameter identifier name instead of the byte position. That system allows test definitions once created to be easily reused in a variety of ECU tests, achieving labor savings and efficiency.

Moreover, the following benefits can be expected from utilizing the CANdela database.

• Use of diagnostic communications function CANoe enables use of a diagnostic console that allows diagnosis requests to be sent with a simple operation. When a diagnosis request is received, the data in the message is displayed as a physical value. Operations on this console can also be recorded as macros with just the touch of a button and played back over and over.

• Analysis of diagnostic communications CANalyzer, as well as CANoe, allows details of diagnostic communications to be analyzed and displayed. That way, details of diagnosis request, diagnosis response, and diagnosis parameters can be displayed on the trace window and time-series wave form of diagnosis parameter values displayed on the graphic window.

• Development of diagnostic functions around the database

After designing diagnosis specifications as a database, developing and evaluating ECUs based on that single


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Fig 4. Image of Testing System (provided by Calsonic Kansei)

database eliminates differences in specification interpretation and evaluation mistakes. This results in efficiency for the above-mentioned test definitions as well as labor reduction while improving ECU quality.

Further system test expansion

Calsonic Kansei will use the VT system to automate I/O testing. It is also looking at using the CANoe simulation function to create virtual nodes for ECUs that the meter control system communicates with and to conduct system testing.

Summary

Overview and outlook

By introducing Vector’s ECU testing solution, Calsonic Kansei gained an environment for automating ECU testing on top of building a system testing environment. The two companies, based on their cooperative relationship, will continue to push forward with expansion of system testing. Mr. Nishida acclaims that, “Thanks to the support of Vector Japan, we were able to build a system testing environment much smoother than initially anticipated. One of the benefits of introducing ECU testing is that if something is wrong with the system, we are able to easily implement feedback testing.”

Looking back on introducing the system

Mr. Hisafumi NishidaDevelopment Reliability Group, Development Division Calsonic Kansei“I am overjoyed that we were able to take the first steps toward building a system testing environment that we were unable to achieve in the past. The testing technology and precision we imagined could be improved from both a hardware and software perspective. We are sure that improved efficiency and reduced labor that are demanded just like quality will naturally follow. We would like to further expand the range of automation in the future based on the testing environment that was built. And we are grateful to Vector Japan for providing test cases and much support.” ■ Contact in Japan for further information:

Sales Division, Vector Japan Co., Ltd. Tokyo TEL: 03-5769-6980 FAX: 03-5769-6975 Nagoya TEL: 052-957-2471 FAX: 052-957-2469 Email: [email protected]

Tomohito KannoTeam Leader, Networks & Distributed Systems (PND) Vector Japan“We are happy that the various functions of Vector products could be used in building a system testing and ECU testing environment. Vector will continue to work to provide products and services to make customers’ testing environments more efficient.


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Building a system testing environment using the VT … Article Building a system testing environment using the VT system The need for system testing is on the rise with the increasing