Last updated on: April 23, 2024, 10:14 a.m.

Test System Development Process

Test Systems are designed to execute automated functional test plans and are most often implemented in production-level fixtures (development-level fixtures also occasionally fall into this category). Simple Test Fixture designs (mechanical-only fixtures) do not require this level of design effort.

FixturFab has developed a standard, comprehensive process for designing Test Systems that will be explored in this series of articles.

Test System Development Process

Manufacturing Phase

Test System Manufacturing Phase

Upon completing design reviews of the mechanical and electrical components, FixturFab proceeds to the Manufacturing Phase. Custom parts are fabricated with 3D printers, laser cutters, and CNC machines then everything is assembled. Rigorous quality checks will be conducted throughout the process to ensure that every part meets the highest standards of performance and reliability.

FixturFab’s shop has various tools that are used to custom-manufacture Test Systems.

  • CNC machines for fixture plate milling & drilling (e.g., FR4 probe plates)
  • Laser cutters for acrylic cutting (e.g., back plates, pressure plates, etc.)
  • 3D plastic printers for a large variety of custom parts
After one month in the new workshop.


First, FixturFab needs to fabricate the custom parts designed for each Test Fixture. A combination of techniques are used.

3D Printing and Laser Cutting

3D Printer enclosure for PLA & TPE printing.
3D Printer enclosure for PLA & TPE printing.

Most Development Test Fixtures are laser cut. Any fixture may contain custom 3D printed parts as required, such as cradles to locate the Device Under Test (DUT) when mounting holes are unavailable.

3D Printer Time Lapse

CNC Machining

Several machines are specially configures for standard plates.
One CNC is reserved for the larger plates.

Most Production Test Fixtures are CNC machined. This is required because the pressure and moving plates are made from FR4 or G10 (fiberglass) so the test probes are consistently accurate at high volumes.


After each part is ready, FixturFab can assemble the Test System.

Test Fixtures typically just need Receptacles, Probes, Guide Pins, and Pressure Pins inserted. As requested, FixturFab can include wired and labeled receptacles.

A Development Fixture

Test Systems typically need instrumentation mounted and wired.

A Test System Instrumentation Rack
The Base of a Panelized Test System


In the next part of the Test System Development Process series, we show how FixturFab automates and reviews the final Test System during the Automation and Qualification Phases.