Ultrasonic Sciences Limited:
Success in the aerospace sector

Customized instead of mass-produced

Bayer and his colleagues were entrusted with the design, construction and installation of a twelve-axis twin-tower system and an eleven-axis gantry system. These systems are intended for testing components made of composite materials for a long-standing customer in the aerospace industry. As Bayer explains, “The custom machines are adapted to the requirements, flexibility and scalability of the application. They are accurate, powerful and equipped with special functions. That is why they are preferred to mass-produced systems.”

“For all of our automated testing systems, we pay attention to precision, resolution, speed control, torque, load capacity, communication interfaces, safety features and durability for motion-related components such as motors,” explains Bayer. Mechanical systems for automated ultrasonic testing systems are often subject to long use periods, repetitive motion and regular changes of direction. They are also usually found in humid environments. Bayer continues, “After discussing our requirements with Martin, we were extremely confident that STOBER would offer us exactly what we needed for the production of our machines.”

Testing large and complex parts

These special requirements called for dual-sided machines for simultaneous transmitted light and pulse echo testing of composite components. Large scanning areas and a range of specialized end effectors make it possible to comprehensively inspect massive components with complex shapes, including wing leading edges, flap fairings and thick composite components. As a result, all the end user’s stringent requirements for mechanical accuracy and ultrasonic testing can be met.

A sophisticated drive solution

Preece explains, “In order to meet the demanding project requirements, we discussed various components from STOBER. After several meetings with Niko Bayer and the USL team, we were able to specify these in detail.” The drive systems on offer could be seamlessly integrated with servo amplifiers or pinion gearing, for example. The solutions include linear and rotary axes with various sizes of servo motors from the EZ series, which are extremely compact and enable maximum torque in combination with high dynamics. It also included the latest generation of drive controllers from the SC6 series, various servo gearboxes selected for their rigidity and precision, and the One Cable Solution (OCS), which reliably connects motors and drive controllers over a length of up to 100 meters.

“Together with USL, we dimensioned and selected our motors and controllers in order to optimize performance based on the type of drive, i.e. rack and pinion, ballscrew or direct drive, and depending on the specific requirements,” says Preece. Bayer and his team often employ a combination of these for different axes on the same machine to achieve the required precision and reliability.

Together with STOBER

“Over the years, we have used many different motors and drive controllers from various suppliers,” says Bayer. “With STOBER, we get the selection, precision, quality and reliability that we need to build our machines.” Another major advantage of this collaboration: “In our experience, STOBER has consistently shorter lead times and better adherence to delivery dates compared to the competition,” says Bayer. He adds, “In the past, we used motors that made it possible to implement values for feedforward control of over 100 percent with regard to friction.” By anticipating and counteracting the effects of friction, systems with this function can achieve smoother, more precise motion. “When we discussed this topic, STOBER was immediately prepared to implement our requirements with the SC6 drive controller. It enables feedforward control values of up to 200 percent. This allows us to position our machine axes perfectly,” says Bayer.

STOBER also supplies integrated synchronous servo geared motors without motor adapters. This makes installation easier thanks to the compact design, low weight and high power density. Bayer says, “The STOBER team is also very helpful when specifying machines, assisting with speed, torque and load calculations. Individual cable lengths allow for more freedom when designing larger machines.”

Successful in operation

oth machines were installed and put into operation in a test facility for Boeing aircraft structures and components. They have exceeded all requirements for mechanical accuracy. “We are very pleased with STOBER solutions and their performance as a core component of our machines,” Bayer says.