A plug-and-play Hyperspectral Imaging Sensor using low-cost equipment

HSIs (Hyperspectral Imaging Sensors) obtain spectral information from an object, and they are used to solve problems in Remote Sensing, Food Analysis, Precision Agriculture, and others.

This paper took advantage of modern high-resolution cameras, electronics, and optics to develop a robust, low-cost, and easy to assemble HSI device. This device could be used to evaluate new algorithms for hyperspectral image analysis and explore its feasibility to develop new applications on a low-budget.

It weighs up to 300 g, detects wavelengths from 400 nm–1052 nm, and generates up to 315 different wavebands with a spectral resolution up to 2.0698 nm. Its spatial resolution of 116 × 110 pixels works for many applications. Furthermore, with only 2% of the cost of commercial HSI devices with similar characteristics, it has shown high spectral accuracy in controlled light conditions as well as ambient light conditions.

Unlike related works, the proposed HSI system includes a framework to build the proposed HSI from scratch. This framework decreases the complexity of building an HSI device as well as the processing time. It contains every needed 3D model, a calibration method, the image acquisition software, and the methodology to build and calibrate the proposed HSI device. Therefore, the proposed HSI system is portable, reusable, and lightweight.

https://www.sciencedirect.com/science/article/pii/S2468067219300513

3D printed hyperspectral imagers to be mounted on UAVs

A team of researchers in Norway has developed a low-cost, 3D printed hyperspectral imager device which could be installed on UAVs to give them advanced imaging capabilities.

A study in the journal Optics Express details how to make the hyperspectral imager for about $700, which is significantly cheaper than existing tools of a similar caliber.

Hyperspectral imaging devices, for those unfamiliar, are not totally unlike color cameras you may be accustomed to, except that instead of only working with a color array based off of just three colors (RGB), they can detect hundreds of colors.

Presently, the research team is working on improving the imaging device’s sensitivity, as it is not quite as powerful as its more expensive counterparts: “There are many ways to use data acquired by hyperspectral imagers,” explains Fred Sigernes, the project’s leader from the University Centre in Svalbard (UNIS) in Norway. “By lowering the cost of these instruments, we hope that more people will be able to use this analytical technique and develop it further.”

The lightweight (200g)  3D printed device was tested using an octocopter UAV. Balanced with the help of a two-axis electronic stabilizing setup, the low-cost hyperspectral imager reportedly “performed well,” successfully detecting different elements of the landscape below it. The research team reportedly used a desktop 3D printer to manufacture customized holders for the device’s optics. According to Sigernes, the team opted to use plastic 3D printing rather than metal to cut back on time and costs: “3D printing with plastic is inexpensive and very effective for making even complex parts, such as the piece needed to hold the grating that disperses the light. I was able to print several versions and try them out,” he said. Down the line, the researchers say metal will be considered to make the device more durable.