Implementing a Drone Survey script#
Ever wanted to capture a bunch of top-down pictures of a certain location? Well, the Python API makes this really simple. See the code available here.
Let's assume we want the following variables:
|boxsize||The overall size of the square box to survey|
|stripewidth||How far apart to drive the swim lanes, this can depend on the type of camera lens, for example.|
|altitude||The height to fly the survey.|
|speed||The speed of the survey can depend on how fast your camera can snap shots.|
So with these we can compute a square path box using this code:
Assuming we start in the corner of the box, increment x by the stripe width, then fly the full y-dimension of
path =  distance = 0 while x < self.boxsize: distance += self.boxsize path.append(Vector3r(x, self.boxsize, z)) x += self.stripewidth distance += self.stripewidth path.append(Vector3r(x, self.boxsize, z)) distance += self.boxsize path.append(Vector3r(x, -self.boxsize, z)) x += self.stripewidth distance += self.stripewidth path.append(Vector3r(x, -self.boxsize, z)) distance += self.boxsize
+boxsize, so in this case,
boxsizeis half the size of the actual box we will be covering.
Once we have this list of Vector3r objects, we can fly this path very simply with the following call:
result = self.client.moveOnPath(path, self.velocity, trip_time, DrivetrainType.ForwardOnly, YawMode(False,0), lookahead, 1)
We can compute an appropriate
trip_time timeout by dividing the distance of the path and the speed we are flying.
lookahead needed here for smooth path interpolation can be computed from the velocity using
self.velocity + (self.velocity/2). The more lookahead, the smoother the turns. This is why you see in the screenshot that the ends of each swimland are smooth turns rather than a square box pattern. This can result in a smoother video from your camera also.
That's it, pretty simple, eh?
Now of course you can add a lot more intelligence to this, make it avoid known obstacles on your map, make it climb up and down a hillside so you can survey a slope, etc. Lots of fun to be had.