computer vision 'Open Data Cam' understands and quantifies what it sees. The simple setup allows everybody to become an urban data miner.
Easy to mount via tripod or straps powered through integrated battery.
Camera and GPU board running open source object detection software.
Splash resistant, easy to assemble and affordable outer shell.
Print and align the folding map.
Slice me nice.
Cut out the materials along the solid lines
Holes for holds
You can use a hole perforator for the holes to strap everything together at the end
If you want to use a battery
Since Li-Po batteries are likely to break if over or undercharged, it is necessary to keep the battery from doing so. For loading there are already perfect chargers to buy. To prevent it from being undercharged, a low voltage battery cut-off does the job. This tutorial explains it really well how to build one yourself: Battery Protection Curcuit Cut.
We made some small adjustments by adding plugs to either cable to make it easier to change the battery later. Put your built PCB in a bag to keep it isolated from the rest and to prevent a short circuit on either boards (e.g. you could use one of the wire zip-bags of the Jetson TX2).
The inner element on cardboard as well as the bottom element for the polypropylene have marks for holes for the ports of the Jetson TX2, just cut the ones out you need to keep it as closed as possible. In my our this was the DC, USB and Antenna ports.
Cut the camera element depending on the webcam you use. The spot is marked, where the lens center should be, just cut parallel to the dotted lines wherever your webcam holder is located.
Glue the tripod nut in place (we used hot glue, not really beautiful, but does the job). The hole has the size of the outer nut elements so it should not be able to turn.
On folding up, the hatched areas should overlap. This is where you should glue/tape/zip-tie them together. Put the webcam onto the socket so that the lens is horizontally centered to the axis mark and put the wire around the wire-holder (keep in mind to leave enough wire to still plug it in later). Fixate the camera using some zip-ties.
Board & Cam mount
Cut up the card board and attachment holes to mount the Jetson board
The camera is mounted on the card board, also the Jetson board will go in here.
This is how we attached the 1/4'' nut for the tripod
This is what your battery-overcharge device should look like (Step 2)
Once plastic and cardboard is cut, it comes to putting everything together. The labels at the holes should help you to locate where everything belongs.
Start with the lid, to understand the concept. Simply fold the sides so the holes lie on top of each other, then put a zip-tie through the holes and pull them tight.
Now the tricky part. Fold the big outer piece like a bag or box of cereals. Fold it up where you made the cuts, the paper folding plan should resemble the inside of the case. Two parts should overlap now, one slightly shorter than the other. Keep in mind to leave the bigger part (the one with the four holes at the top) on the outer side.
Put the bottom part into the main part, having the holes on top of each other. Then, again, pull the zip-ties through and tighten them. On some holes there should be up to four layers of polypropylene.
On one of the upper corners lie also two holes on top of each other. Tighten them as well.
If the two polypropylene layers are assembled, insert the previously built cardboard inner element. Same here, put a zip-tie through the two double holes and pull them tight.
Finally put the handle with the four holes on the outside of the four holes of the main case and combine them. To be safer regarding the splash proof aspect, put some duct tape on the holes from the inside.
Start with the lid
To get a hang of how assembly works, start with the the lid. It should look like this after it's been folded and zipped.
Fold and zip the box
The bottom and the sides assembled and zipped should look a little like this.
Close up of zip connectors
The box should fit together like this to protect it's content.
Put the lamp socket through the hole in the case and fix it with the lampshade holders. This is where the camera should peek out.
Once you’ve built your traffic cam you’ll want to start counting traffic right away. That’s why we’ve created an open source version of what we built to make the cam work. You can find the installation guide on GitHub
The software running on the jetson board will allow you to draw lines into the video stream. As objects cross this line, they will be counted, no matter in which direction. Add more lines to count on multiple spots. After finished you can export the data by hitting the export button. All data processing happens locally on your Jetson board.
As objects cross this line, they will be counted
Export your collected data as csv
Concept & Idea
Benedikt Groß, Markus Kreutzer, Raphael Reimann
Thibault Durant, Thomas Derleth, Marco Biedermann, Joey Lee, MESO Digital Interiors
Raphael Reimann, Thomas Thöne, Olivier Brückner