One of the biggest challenges for engineers when launching a product is to optimize it based on the results of testing and evaluating its performance.
Along with the optimization process come two more challenges, the strategic and logistical:
- the time that puts continuous pressure on any project manager and also on the product development team;
- the physical space used in the laboratory and the location at strategic points in the testing process of the equipment necessary to meet the testing requirements.
Challenge
Development of an automated testing system for the optimization and complete characterization of the product according to the company’s international and internal standards.
Another important feature of this test system was the possibility of introducing several sensors simultaneously and selecting them in the climate chamber. This aspect allowed the realization of statistical measurements of more efficient characterization and optimization of the product and the possibility of selective testing.
The above-mentioned challenges were solved by creating a rack type system, with equipment that allows testing the product from a parametric and functional point of view. It also allows the execution of the tests necessary to optimize the product.
Solution
The focus of the test solution was on the Keysight unit of measurement and switching, which allowed both current requirements to be met and future measurement and testing capabilities to be expanded. Thus, the developed solution became scalable.
The second step was to identify a rack that would allow the incorporation of the necessary equipment, precise temperature control and efficient wiring management.
The testing of the product on the whole temperature spectrum was performed by installing a mechanical system for selecting and moving the target (design designed by IFM Efector) on the climate chamber. This mechanical system is powered by 2 stepper motors – DC controlled from the automation software of the entire test process.
The equipment was connected to the internal LAN of the rack, thus allowing external communication via the wireless network. The management of the connections between the climate chamber and the rack was intended to be as simple as possible, thus facilitating the physical movement of the equipment by simply disconnecting the power cord from the network.
Software Automation
The Thermal Chamber Automation application aims to automate the testing procedures Sensing Range + Hysteresis, Useful Sensing Range, Voltage Drop, Leakage Current, No-Load Current and Short-Circuit Threshold for inductive sensors. The software offers the possibility to connect, control and monitor the equipment in the rack, the climate chamber and the mechanical sensor selection system.
The software automation solution began by defining the system architecture based on customer specifications. The application is designed to meet the criteria of scalability, extensibility and modularity. The next step involved the development and integration of drivers for Vötsch Climate Camera, Stepper Motor, Digital Comparator, Rohde & Schwarz Power Supply, Keysight Switch Unit, Keysight Electronic Load, Keysight Digital Multimeter and Rohde & Schwarz Oscilloscope.
Through the climate chamber automation application, the desired temperature in the climate chamber will be set and the thermal equilibrium will be expected to be reached before the start of the test. The test will continue by calibrating the mechanical system and performing the distance measurement of the 6 sensors in the climate chamber.
The software allows you to select parameters and choose test types. For further verification of the results, the user can also select the number of repetitions of the test. Different results between repairs (identical test parameters) indicate a product defect.
During testing, the user has the ability to view live test results via the graphical interface and can check the status and progress of the test in this interface at any time. Test data reports, including graphs, can be generated and saved at the end of each test.
Parts of the test system:
Vötsch Climate Chamber – change and maintain the desired temperature for DUTs;
Stepper Motor – target displacement for calibration, sensor position change and measurement of the necessary parameters to solve the tests of Sensing Range + Hysteresis, Useful Sensing Range, Voltage Drop, Leakage Current, No-Load Current and Short-Circuit Threshold;
Digital comparator – display, measure and save the distance the target is from the tested sensor;
Power Supply Rohde & Schwarz – power supply sensors;
Keysight Unit of Measurement and Switching
Electronic Load Keysight
Digital Keysight Multimeter – measuring physical quantities that the Keysight measuring and switching unit could not perform;
Rohde & Schwarz oscilloscope – measurement of dynamic and transient parameters.
The user interface has been structured in 3 parts:
Configuration – in turn divided into 2 parts: instrument configuration and test configuration.
Instrument Setup allows you to view the status, types, and models of instruments used and allows you to select VISA I / O communication resources. The application stores successfully completed connections and perform the automatic connection to the next runs of the application.
The test configuration is used to set the general parameters of stepper motor running – DC, reset the motors, read the status of the digital comparator power supply battery, select the test data (project number, item number, target size, etc.) and generate Excel reports with test results. Reports are generated and saved locally by simply selecting the desired test from the list of tests run so far;
Test Setup – define setup for power supply, climate camera, the configuration file for Keysight unit of measure and switch, setup file for oscilloscope and set parameters specific to the test run; Also integrated here is the option to manually run the test for the execution of short sequences, specific to the test procedure.
Graphs – used for the Sensing Range + Hysteresis test where it helps the user to easily visualize the evolution of the sensing range and hysteresis at different temperatures.
When handing over the project, after training the staff who will use the equipment, the equipment user manual was also handed over, a manual that describes in detail the software application and how to use it.
