This Augmented Reality Workbench Provides Magical PCB Debugging Functions

Debugging hardware is hard. Maybe your prototype worked perfectly, but your shiny new PCB won’t power on. Maybe you’re attempting to debug a PCB designed by someone else and you don’t even know where to start. This work requires identifying and locating components, finding specific pins, referencing schematics and layouts, and probing and measuring between test points. Quick, measure the voltage between resistor R32 and pin 3 of the 74HC595 IC while pressing button 6! To make the PCB debugging process easier, this augmented reality workbench provides seemingly magical projection.

ARDW (Augmented Reality Debugging Workbench) is the result of work from several engineers at the University of Washington and Carnegie Mellon. It is a complete system that combines augmented reality, projection mapping, computer vision, smart measurement tools, and sophisticated software. The system’s physical hardware sits on any workbench. It is quite large and requires substantial framework, but it isn’t impractical. That framework supports tracking cameras and a projector, which are key to ARDW’s functionality. The software works as a plugin for KiCAD PCB design software, which is open source and very popular in the electrical engineering industry.

A user begins by placing their PCB on an antistatic mat on the workbench. Then they select their PCB design in KiCAD. The ARDW system will use its cameras to detect the position of the PCB and then project an overlay onto the PCB. The overlay can be general, like a view of the traces. But that’s just the beginning. It can also highlight specific components and even pins on those components. A user can, for example, select that 74HC595 IC (a shift register) in the software and ARDW will highlight it on the PCB so the user can find it quickly and easily. The user can also ask ARDW to highlight a pin on the component, so they can find a probe point.

This works both ways using a set of special multimeter-style probes. The user can touch a probe to a component and ARDW will provide that component’s name and label onto the workbench. It will also select the component in KiCAD, letting the user find more information or modify the design.

Those functions alone would be incredibly useful, but it doesn’t stop there. ARDW can facilitate automated debugging and quality assurance (QA) workflows. For example, it can highlight any areas of the PCB where components should be omitted, which is great when debugging later iterations of PCB designs. It can also guide users through testing by highlighting probe points. When the user probes the points, the software records the measurement and compares it against expectations. If a PCB requires several tests, a user can complete all of them in a quick series of probes—finishing the entire QA process in just minutes or even seconds.

The utility of ARDW should be obvious, but it does have some downsides. First, it is relatively expensive and therefore isn’t very practical for hobbyists or small labs. It also has trouble with very small components, which are difficult for the projector to highlight with accuracy. Even so, the “magic” here is so useful that we expect to see this technology — or at least something similar — out in the wild soon.