Robotic Work Cell Conducts High-Throughput Testing in an Instant

A commercial robot has been developed that conducts high-throughput testing to determine the performance and properties of a manufactured part.

Sandia National Laboratories designed and built the Alinstante — a six-sided work cell, similar to a circular desk, with a commercial robot at its center — which speeds up qualification and testing of custom 3D-printed parts.

Sandia National Laboratories materials scientist Brad Boyce watches as the Alinstante robotic work cell scans a 3D-printed part to compare what was made to the original design. Courtesy of Randy Montoya/Sandia National Laboratories.

"In traditional manufacturing of metals, there's a lot of experience and finesse in process control to produce metals with uniform properties,” said Sandia materials scientist Brad Boyce. “When we went to laser manufacturing we had to take a step back and rethink qualification.”

The commercial robot sits in the center of a hexagonal work cell with up to six petal workstations around it. Each workstation can have a different commercial or custom testing system, and the workstations can be swapped in and out depending on the kind of tests needed.

Sandia mechanical engineer Ross Burchard led the design of the work cell.

"My challenge was: How do you come up with a work cell with one robot and multiple testing stations that's also modular and scalable?" Burchard said.

Burchard and his team adapted commercially available hardware for efficiency and to save money.

In addition to constructing the hexagonal floor plate and pedestal for the commercial robot, the team installed safety light curtains wherever a person and the robot might interact. The light curtains are set up so that if a person reaches into the work cell, or if the robotic arm reaches out of the work cell, the light beam is broken and the robot automatically stops.

The team hopes to add a user interface that will allow a nonexpert to place their parts on a tray in the parts rack, select a few tests, and get their data automatically.

The prototype Alinstante work cell has two testing stations and a rack where users can place their parts. The first station is an off-the-shelf structured light scanner that can convert a scan into a 3D model for direct quantitative comparison to the original intended design. The second station is a load frame for testing physical properties, such as tensile and compression testing, which is pushing on an object until it crunches.

The Sandia team plans to add a laser-induced breakdown spectrometer to Alinstante, which would be useful in determining the batch-to-batch consistency in the chemical composition of parts in a minimally destructive manner.

"Sandia has testing labs that can perform all of these tests; however, it takes a few weeks to schedule each of them, which can add up to one or two months of testing,” Burchard said. “Alinstante can reduce the scheduling burden for the testing, greatly speeding up the turnaround time.”

Alinstante also reduces the chance for human error and produces data that is more consistent and reproducible than human testers.

X-ray tomography, corrosion testing, and density measurements are just a few examples of the tests the team would like to add to Alinstante.

The Alinstante team is looking for partners to support the development of new modules that would meet its rapid testing, prototyping, or R&D needs.