Researchers from the Ong Lab are developing a multi-axial shear displacement and force sensor for biomedical and industrial applications. The sensor is based on optoelectronic coupling between broad spectrum light from an LED, reflected off a color pattern, and measured via a photodiode with bandpass filters at the red, green, and blue wavelengths. The sensor operates in a reflective mode, whereby the LED and photodiode are separated from the color pattern by an elastomeric media, allowing measurement of both displacement and force.

Historically, size, mass, and power constraints have limited the use of other shear sensors for wearable applications. Our optoelectronics-based approach is comparatively, smaller, lighter weight, and lower power than traditional capacitive designs. Furthermore, the sensor can differentiate between horizontal and vertical shearing; this feature has largely been limited to heavy strain gauges that require a wired power source. The sensor is also contactless with a scalable design to expand its use for a variety of biomedical and industrial applications.

Related Publications:

Mohler, A.; McGeehan, M.; Ong, KG; Hahn, M. Evaluation of  a Multi-Axial Shear Sensor Using a Multi-Layer Perceptron Neural Network. IEEE Sensors Letters

Ahamed, S; McGeehan, M.; Ong, KG. 2024. An Optical Sensor For Measuring Horizontal Displacement Between Parallel Surfaces. In press.

Pennell, Z; McGeehan, M; Ong, KG. 2023. An optoelectronics-based compressive force sensor with scalable sensitivity. Sensors. 23(14), 6513. DOI: https://doi.org/10.3390/s23146513.

McGeehan, M.; Karipott, S.; Hahn, M.; KG. 2023. A wearable shear force transducer based on color spectrum analysis. Measurement Science and Technology. 34(2023).

McGeehan, M.; Karipott, S.; Hahn, M.; Shuaib, M; Ong, KG. 2022. Optical-based sensing of shear strain using reflective color patterns. Sensors and Actuators A: Physical. 335(1).