Efficiently Managing UUT Variants in Manufacturing Tests with PTEM
PathWave Test Executive for Manufacturing (PTEM) is designed to handle multiple UUT variants effortlessly.
Before smartphones became essential, product designs were straightforward and focused on single functions. Devices were built for a single purpose: a radio played music and delivered news—nothing more. With the rise of smart technologies, products now go far beyond basic functionality, offering hundreds of features and applications. These are often tailored to the preferences of the consumers; giving them exactly what they need at the most affordable price. A specific product today can have multiple versions, each offering a different feature. This evolution has significantly changed product complexity and testing requirements.
What does this mean for the manufacturing test process?
In the manufacturing environment, a product undergoing test is called the unit under test (UUT). Multiple versions of the UUT translate into different variants of test sequences and parameters; a unique set for each of the UUT versions. Typically, variant-specific tests stand for more than 50% of the overall test plan, while the rest is generic. Hard coding these variant sequences into separate test plans may seem straightforward, but it results in extensive duplication of the generic tests. Maintaining such a fragmented collection of test plans quickly becomes inefficient and error prone.
How can we address this challenge effectively?
PathWave Test Executive for Manufacturing (PTEM) provides the solution.
Figure 1. Select and switch variants easily on the Manufacturing User Interface.
PTEM gives you direct access to all variant-specific parameters and test sequences in one test plan interface. You can create as many variants as you like in your test plan and decide which test parameters and sequences to execute for each of the variants. Switching between variants during production is as simple as a single click on the manufacturing interface.
Figure 2. Variant-specific Test groups control what tests to execute for each variant.
In the test plan editor, you create test groups that consist of the unique test sequences for each variant and PTEM automatically selects the group to execute according to the selected variant. You can create multiple test groups for a variant throughout the test plan and PTEM manages all of them automatically without needing you to add any conditional branches to check for the variant type. This approach keeps the test plan streamlined and easy to maintain.
Figure 3. PTEM executes the Test groups that only belong to the selected variant.
In the example above, the test plan has 3 test groups, each holding the test sequences for one of the UUT variants. The test steps not within these test groups are generic steps independent of any variant choice. Only one type of variant can be selected for each run of the test plan. During runtime, PTEM automatically disables the test groups that do not belong to the selected variant type.
Figure 4. Variant-specific parameters allow different values to be defined for each variant.
In some cases, having a variant does not just mean the need to test it differently. The variant may require a distinct set of values to its test parameters. The varying parameters can be things like test tolerance, constant multipliers or offset, or different command strings to talk to the UUT. To make a parameter of a test step variant-specific, you must assign it to a variable first before configuring the different values it holds for each variant. The test steps execution is still the same in this case, just that its parameters are now dependent on the variant choice.
Figure 5. Test plan execution with selected variant A338s.
Figure 6. Test plan execution with selected variant B212.
Figure 5 and 6 shows the Manufacturing User Interface (Mfg. UI) running with variant-specific variables and test groups. The screenshot on Figure 5 shows the results of the run with variant type A338 selected. You can see that only Test Group for GC-A338s is active while the other two groups stay inactive, and variant-specific Time Constant variable is being set to 3.511 while executing in the test sequence. Now let us select a different variant type and run the same test plan. The screenshot on Figure 6 shows the result of the run with variant B212. You can see that Test Group for GM-b212 is now active, and the Time Constant value has been changed to 2.541.
PTEM’s variant management makes it simple to handle UUT variations without adding extra conditional coding or branches. Taking these extra test steps off the test plan lightens the load on the PC resources during execution and makes it easier for troubleshooting and maintenance.
Stay tuned for more exciting features in upcoming PTEM releases.
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