Measure the flight path
Since Sleipnir Velocity works by measuring the time it takes to fly a certain distance two criterias are an absolute must for this system to work. You need to be able to measure up a flight distance and the cameras have to be pointing exactly 90 degrees from the flight direction, we will work with 100M for the example but longer/shorter is possible, longer will give you better accuracy. You can use measuring tape or a laser meter to measure up 100M, this is quite easy but you may have to do it in steps depending on the equipment you use. This illustration describes what we are after.
The 30 meter line between point 2 and 3 is what you need to have at an exact 90 degree angle from the flight line. We use good old Pythagorus theorem to achieve this.
To make it more manageable cut your 100M stretch in half at 50M, this will be your “b” line, the 30M is the “a” line. The c line is calculated to approximately 58.31M. This is what you have to measure up in both the right and left direction. This will take some time to do correct so be sure to have some way to make the points permanent. Once your points measured installing a complete sleipnir system takes about 30 minutes to an hour.