Team # 201906725 Page 4 of 21
2. Problem analysis
2.1 Analysis of question one
In view of the first problem, the topic requires the UAV to study the flight altitude
under the condition of constant flight speed and shooting angle. It is found that UAV
squint photography is widely used in aerial photography because of its high accuracy.
Therefore, this paper studies the aerial photographing behavior of UAV in the case of
tilt photographing. Because the accuracy of camera acquisition information is
reflected by resolution, the best aerial photographing height of the whole area that can
be photographed by UAV can be obtained by establishing the model of resolution,
flight height and angle in the research, and the height range is the range higher than
this optimal aerial photographing height. And the optimal height of the aerial
photograph under different flight angles is obtained.
2.2 Analysis of question two
In view of the second problem, it is required to study the flight angle of UAV
when the flight speed and shooting height of UAV are constant. Problem 1 has
calculated the optimal height of UAV in different aerial angles. In the actual ground
conditions, the optimal height of UAV changes with the actual terrain fluctuation. The
actual ground conditions discussed in this paper are high-rise building area and
mountain area. By setting the optimal aerial height as the objective function, the
shooting area of UAV is studied, and the optimal range of UAV shooting angle is
obtained.
2.3 Analysis of question three
For the task three, the mission requires the UAV to fly at a fixed speed and
altitude, and is tracking the object on the ground for a specific motion trajectory to
calculate the change in the shooting mode of the drone. The drone has three linear
motions (front and rear, up and down, left and right) and three angular motions
(rolling, pitching, yaw). According to its dynamics and kinematics feature, Small
disturbance state space equation, which involves with the longitudinal and lateral
directions of the final moving object of the drone, can be obtained.
2.4 Analysis of question four
In the task four,the mission requires the drone to avoid obstacles on the path,
calculate the optimal flight speed, flight altitude and photographic angle, and conduct
data simulation experiments. We use obstacles (signal towers, utility poles, and
houses) as peaks, fit the terrain parabola function, construct the obstacle space
envelope surface, and find a series of path points that meet the requirements by
finding the corresponding interface. These point interpolations fit the feasible path.