Sensor thinner than a human hair could trace heat, pressure and wear at 7,252 psi

A new sensor thinner than a strand of hair that is being developed by scientists in Germany could reportedly measure temperature, pressure, and lubricant thickness directly inside hydraulic pumps, and detect early signs of wear.

The device comes from the Fraunhofer Institute for Surface Engineering and Thin Films (IST). It is intended to make monitoring hydraulic pumps easier. The project, known as ThinSor, also involves scientists from the University of Magdeburg and RWTH Aachen University.

The sensor is composed of a layer system that’s just a few micrometers thick. It is applied directly to a pump’s valve plate, where it could monitor critical operating conditions without requiring holes or other modifications.

According to the researchers, it could measure pressures below 7,252 pounds per square inch (50 MPa), along with temperature and lubricant thickness. In addition, the system could improve hydraulic pump efficiency, extend pump lifespan, and reduce unexpected downtime.

How the sensor works

Axial piston pumps rely on pistons that move back and forth along or at a slight angle to a rotating drive shaft. These are commonly found in hydraulic systems, where they move fluid under high pressure. Their performance depends heavily on the interaction between the rotating cylinder barrel and the stationary valve plate, which are separated by a thin film of lubricant.

The lubricant reduces the friction between the two parts and prevents them from wearing out too quickly. Still, measuring what happens in this narrow gap during operation remains difficult.

Traditional methods often require drilling holes or modifying pump components to install the sensors. These changes can, however, affect how the surfaces interact and even influence the measurements themselves. To address this, the team’s sensors sit directly on the valve plate’s surface.

“This should enable all three parameters to be measured simultaneously and with high temporal resolution exactly where they occur – without the need for time-consuming post-processing of the component,” the team added.

A pressure challenge

The team shared that measuring lower pressures at the contact point presents a huge challenge. The sensor must detect pressures below 7,252 pounds per square inch (50 MPa), which is lower than what most existing sensors can measure.

The researchers must therefore make the sensor more sensitive, so it can capture accurate readings without interference from background noise. At the same time, the ultra-thin layers must withstand the considerable mechanical forces produced during pump operation.

The thin-film sensor system is applied directly to the surface of the valve plate. Credit: Fraunhofer IST

According to the team, the technology could reduce the need for prototypes, detect early signs of wear, and help engineers plan maintenance to prevent breakdowns. “The measurement data obtained is intended to help design fluid-technology components more precisely and to validate simulation models and digital twins,” the institute said.

Moreover, it could eventually support continuous monitoring of both new and existing hydraulic systems. It may also have applications beyond hydraulic pumps. “Applications involving bearings, gears, and shafts already demonstrate the potential of this technology,” the researchers concluded in a press release.

The ThinSor project began on June 1, 2026, and is scheduled to continue until November 30, 2028. Its ultimate goal is to make the measurement technology suitable for industrial applications.

Source: https://interestingengineering.com/innovation/sensor-monitors-heat-pressure-wear