Blogs

One of my projects is about establishing a solid, low-latency HD video link for FPV, SAR or surveillance and using accessible, affordable technology to do that. This is talking $4,000 for the entire setup here, which is mostly the macmini+720p goggles and which are reusable in different contexts.

The OSD is painted on the ground station (a mac mini) and visualized through the HD goggles (HMZ-T1). Even though the letters look pretty small, it's easier to see them through the goggles than on a regular computer screen. 

In the past year I worked on refining this application and all the required settings for wifi, encoding, decoding to establish a relatively low-latency video link (120-150ms, relatively: for this type of technology). The telemetry data link that transmits all data from all onboard sensors at a rate of 30 Hz paves the way for a host of new ground-based applications. Examples include the integration with map and DEM data for improved navigation and virtual 3D overlays to make tunnels or paint the location of "buddies", "spotters" or other points of interest. If the lens properties are known and the camera is precisely fitted, this is not incredibly hard to achieve.

The OSD's bottom bar is also new and requires some explanation. Most OSD's provide raw data as in the top bar, data which has to be interpreted by the pilot during flight. In this app I'm reinterpreting the data based on work done in Cognitive Work Analysis (CWA). An example is that the pilot's primary concern is not the capacity left in the battery, but the distance that the battery still allows him to travel using that capacity and whether that's enough to make it home. The bottom bar thus relieves the pilot of these calculations and the bottom bar can be scanned in short time. If all is green, there are no immediate concerns. Bars reducing in size and changing color to red demonstrate a decrease in the available affordance for that operational concern.

Anyway, I gathered a lot of data and observations in this field test and I'm already working on improving those. This includes the causes for the video stutter, the failure of the telemetry link and so on. Both launches failed because the bungee cord got caught in the motor (twice!). I fixed that and managed to make another third successful launch, but that  unfortunately didn't get recorded.