“The aim is to record the entire trajectory of a stone experimentally, including information on rotational speeds, impact forces, jump heights, etc.”
This experiment conducted at Chant Sura on the Flüelapass in Swizterland may have been done for serious scientific research but that was downright badass. The 800 kg concrete rock was fitted with sensors to measure the rotations and accelerations in all three axes and was rolled down a test area with about 40 degrees of pitch and 300 meters long. Scientist from the WSL Institute for Snow and Avalanche Research SLF also synched the data with photogrammetry for the first time:
“In addition, the researchers are using synchronized photogrammetry for the first time. At the same time, two cameras from different viewing angles record two images per second. This allows conclusions to be drawn on the leaps and, in the ideal case, the images allow to reconstruct the complete trajectory of the stone from the stereobooks in 3D.”
It may look chaotic in the video but these sensor laden concrete stones provide valuable data for hazard analysis and mapping:
“Results from experiments already carried out suggest that wheel-like movements in rockfall processes are even more important than previously assumed. The insights gained are continually integrated into the planning of further experiments and the further development of sensor technology and data acquisition. RAMMS :: ROCKFALL simulations can now be compared with experiments. This helps to bring the simulation program closer to reality. Practitioners should therefore be provided with a valuable and calibrated instrument which will support them in their work on hazard analysis and mapping.”
To read a complete article explaining the experiments go here.
[images from slf.ch]