A robotic system that automates the entire wire harness assembly process — long considered one of the hardest tasks in manufacturing to mechanize — is heading for commercial launch early next year.

Cellios GmbH, a spinoff of the Fraunhofer Institute for Manufacturing Engineering and Automation IPA, developed the modular system in partnership with connector maker TE Connectivity and MVTec Software GmbH. The system runs on Kuka six-axis robots and Omron SCARA robots and covers connector singulation, crimping, cable routing, taping and end-of-line testing.

The core technical problem is the material itself. Wires and cables are flexible and dimensionally unstable; they shift position during every processing step, which defeats preprogrammed robot paths. The hardest step, according to the engineers, is cable routing and the contact insertion that follows.

"During contact insertion, a robot must reliably insert the gripped crimp into the designated cavity of a connector," explains Frank Nägele, Ph.D., chief technology officer at Cellios. "Because the position of the cable end changes during the preceding process steps, a preprogrammed robot position alone is not sufficient."

Two cameras close the loop

The Cellios answer pairs two 2D cameras with machine vision software. The robot first brings the gripped component to a camera, which determines the crimp's current position and orientation. That data becomes correction input for the robot's movement.

A second camera measures the target position on the connector. The robot then corrects its path and places the crimp precisely, compensating for geometric deviations caused by the cable's flexibility and upstream processing.

"Without precise measurement, we would not be able to achieve the 0.1-millimeter insertion accuracy we need to align the connector with the crimp," says Nägele. "Machine vision provides the required geometric accuracy."

Vision alone does not finish the job. "During the actual insertion process, force control comes into play as well," Nägele notes. A force-torque sensor on the robot monitors the forces during insertion and controls the process.

"This way, the system combines two different sources of information: machine vision determines where the component and target are located, while force control manages how the crimp is inserted," he says. "This combination enables the robot to perform a process that previously required human vision, concentration and dexterity."

The software layer

Cellios built the image processing on MVTec's MERLIC platform. Matching technology determines the position and orientation of crimps and feeds the corrective movement data to the robots. MERLIC integrates with the robotic system through MQTT and REST interfaces.

Why it matters for plant siting

The economic argument goes beyond cycle times. Wire harness production today depends heavily on manual labor, which has pushed it toward low-wage countries and long supply chains.

"Automation can help make wire harness production economically viable in high-wage countries," says Nägele. "This can enable production processes to be located closer to their respective sales markets and shorten supply chains."

He also claims process-quality gains. "At the same time, the digital monitoring of the insertion processes provides greater process control and complete traceability of wire harnesses," says Nägele. "Additional benefits include reproducible quality, flexible processing of different wire harness variants and improved traceability."

Those claims remain to be tested against volume production data once the system reaches the market. Wire harness automation has a long record of pilot projects that stalled when confronted with variant diversity and cycle-time demands at scale.

Cellios says it eventually plans to extend the technology to other applications, including control cabinet wiring and enhanced quality inspection.

What to watch: The commercial launch, slated for early next year, is the first milestone. After that, the indicator that matters is a confirmed installation at a harness maker or OEM plant running multiple wire harness variants at production tempo — the test that manual assembly has so far resisted.