Laser tracking LAMM adds accuracy to robotic manufacturing systems

The accuracy of robotic manufacturing systems could be improved at a fraction of the cost of using conventional measurement technology, thanks to the development of LAMM, a new type of laser tracker.

Reflex Imaging’s Malcolm Humphrey, chief technical officer (left) and Peter Hart, chief executive officer (right) with Thomas Hodgson from IMG (centre) putting the LAMM sensors to the test at AMRC’s Factory 2050

The Laser Metrology Module (LAMM), which uses a laser to track a target and generate coordinates for that target, has been developed by Horsham-based Reflex Imaging.

The Micro-Electro-Mechanical Systems (MEMS)-based device fires a laser beam and then very accurately measures the reflections.

Reflex Imaging originally developed the system for use in medical applications but has been working with researchers at the University of Sheffield Advanced Manufacturing Research Centre (AMRC) to investigate its use in high-value manufacturing.

In particular, the team has been investigating the use of the sensor technology in robotic manufacturing systems, according to Thomas Hodgson, the large volume metrology lead at AMRC’s Factory 2050, who led the project.

“Robots are very repeatable, meaning they go to the same place every time, but they are not very accurate, so if you tell them to go to an absolute coordinate they will likely miss by a couple of millimetres or so,” said Hodgson.

So for high-value manufacturing tasks, companies can invest in in-situ laser trackers to improve their accuracy. However these laser trackers typically cost anywhere between £80,000-250,000, he said.

The trackers are often used in robotic drilling, for example, to ensure the robot is in the correct position before it begins drilling the hole.

“With these low-cost sensors, you have the scope to improve your working volume because you can have multiple sensors, which you can then leave in-situ, so that you have a constant, closed-loop manufacturing system,” he said.

The difference in cost is around the same as that between buying a house and buying a car, he said.

The Catapult-funded collaboration between Reflex Imaging and the AMRC’s Integrated Manufacturing Group (IMG) involved two workshops at the AMRC’s Factory 2050 to develop use-cases and demonstrators for the LAMM.

The idea was to find application areas within the high-value manufacturing industry and help Reflex develop the sensor to suit these applications.

The initial workshop was designed to understand the technology and identify possible applications, while the second workshop focused on specific manufacturing tasks.