VegSense is useful for forest studies

Rice researchers set up a Microsoft HoloLens as a mixed reality sensor to feed VegSense, their application for measuring undergrowth vegetation, plants growing between the tree canopy and the ground.

A proof-of-concept study by PhD student Daniel Gorczynski and life scientist Lydia Beaudrot shows that VegSense could be a suitable low-cost alternative to traditional classical field measurements.

your studies in Methods in ecology and evolution shows that the hardware-software combination excels at quantifying relatively old trees in the wild, which is a measure of the overall health of a forest.

Gorczynski came up with the idea of ​​trying HoloLens, which is widely marketed as a productivity tool for manufacturing, healthcare, and education. He developed the open source software for the device and found that while the combination is less effective at picking up seedlings and small branches, there is plenty of room for improvement.

Gorczynski said he was introduced to mixed reality detection while studying at Vanderbilt University and saw its potential for biological studies. “It seemed like some kind of natural seizure,” he said. Gorczynski brought the idea to Beaudrot in 2019 shortly after arriving at Rice.

The combination of off-the-shelf hardware and custom software costs far less than lidar-based (for “light detection and ranging”) systems most commonly used in three-dimensional field studies, said Gorczynski, who developed VegSense on a platform that’s more 3D-centric -Games geared and interactive experiences as hard science.

Field tests in Houston’s Memorial Park have shown that, at least for mature trees, the smaller solution is just as good. In their case study, VegSense easily spotted 48 out of 50 such trees in the target area, a circle about 30 feet in diameter that Gorczynski walked along, looking up, down and around to create the 3D database. (“Imagine an asterisk with a circle around it,” he said, describing the data collection pattern.)

“For this study, we really wanted to consciously try to replicate more traditional measurements of vegetation structure in the undergrowth,” Gorczynski said. “We tried to get that level of detail.”

What he sees as he scans the environment is a hologram-like grid pattern that traces the surfaces of the vegetation. “What’s really cool about it is that you can see what the scanner picks up, but also the points that you missed,” Gorczynski said. “The idea is that the mesh covers as much vegetation as possible, because that’s the only way to get the best scan.”

“The results were so beautiful that Dan quickly wrote them down for publication,” Beaudrot said, noting that Gorczynski expanded his validation of the equipment during a subsequent field trip to Tanzania, the focal point of one of the 15 tropical forests in a recent rainforest study rice group.

“This device can facilitate a lot of great ecological research, especially because it’s so inexpensive,” she said. “Gathering vegetation information on the forest floor right now is really hard to do without a lot of manual labor or a really expensive lidar system.”

“So this is a breakthrough, low-cost device,” Beaudrot said. “It won’t give you the same resolution data as lidar, but this is just the first application. We hope that making VegSense open source to the ecological research community will stimulate all possible avenues of development.”