New Developments in Multi-Spectral Drone Imaging in the Ultraviolet Band

Here, I report a brand new filter-based modification of a 4K Camera, The Hasselblad 20MP Camera onboard the DJI Mavic 2 Pro, to develop an ultraviolet (UV) imaging system for remote sensing.

This was achieved via testing and adapting new quartz-based Ultraviolet imaging filters as well as thin film solar-filters in conjunction with commercial cameras modified using "hot-mirror" filter removal.

The Hasselblad cameras used in the Mavic 2 Pro contain one of the best passive imaging,
complementary metal-oxide semiconductor (CMOS) sensor, A 1-inch sensor with 20 megapixels which can be set to image using very high exposure to record in the Near-UV.

The utility of these devices is demonstrable for applications at wavelengths as low as 310 nm,
in particular for sensing vegetation in this spectral region. For this a novel UV-based remote sensing
classification index has been developed for use in experimental Ultraviolet aerial imaging using
drones.

Given the relatively very low cost of these units as compared with other cameras in this field of imaging, and  the fact they are integrated on a superb platform for deployment, a semi-autonomous aerial vehicle, they are suitable for widespread proliferation in the field of environmental monitoring
in a variety of UV imaging applications, e.g., in atmospheric science, vulcanology, oceanography, forensics, monitoring of industry and utility structures (in particular powerlines and smokestacks), fluorescent tracer measurements and general surface measurements.

I am beginning experimental testing of this technology in Gran Canaria over the next few months. I have already begun to construct test image datasets for analysis using a prototype Normalized UV Absorption Index (NUVAI)

With this index I hope to be able to classify vegetation and surface features based on their UV absorption characteristics and compare with the NDVI taken using the same camera with my already extensively tested Infrared Filters.

Ultraviolet Drone Aerial Image

Using Python coding I have digitally processed some of the test images already and hope to perform similar work as used in my near-infrared (NIR) drone research. 

Ultraviolet Reflectance with an NDVI-style Key

All coding available through my GitHub Repository - https://github.com/MuonRay/Ultraviolet_Image_Python_Processing_Codes

Ion Propulsion of Magnetic Levitating Graphene E-Sail: "Tesla-Kinesis"

In this short experimental demonstration, I share a concept of induced ion propulsion using positive ions that create a wind that can push a thin-film of graphene that is kept levitating at effectively zero-G using a rare-earth magnetic track. This is, in effect, an ion "E-sail" (electric sail) that can capture the momentum of the ions emitted and transfer them into motion in the direction of the ion flow.

The ion source is a modified Tesla coil, a high voltage source, that causes breakdown of air above a sharp steel tip creating a streak of positive ions that move away from the source in a direction toward the sample being probed and propelled.

This system is a simulation of the solar-wind that is whipped up by the high temperatures and magnetic activity of the stars themselves. The Sun produces a significant solar wind, made up of protons and helium nuclei, which are emitted at high velocities from the solar atmosphere, the corona, and solar surface during solar flares and coronal mass ejections. The energy that is emitted in these eruptions, translated into the stream of high velocity charged ions, is perhaps the greatest free source of space propulsion and could, potentially, carry spacecraft equipped with massive solar sails to the outer reaches of the solar system at speeds that would be impossible to achieve using chemical propulsion or gravity assists and without the need for onboard propellant.

Indeed, interstellar space travel could be achieved using this effect over the more energy intensive photon-assisted propulsion which is also another interesting avenue of research which could utilize the high durability and strength of graphene material. Graphene also has the advantage of being highly resistant to radiation and the electrical current induced by ion capture may itself be used as an energy source for the spacecraft with a large enough sail. In any case the effect itself is interesting and demonstrates, if nothing else, the principle of converting electrical energy into kinetic energy and the visual demonstrations of the concept of an ion wind.