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Monocular Vision System for Fixed Altitude Flight of Unmanned Aerial Vehicles.

Huang KL, Chiu CC, Chiu SY, Teng YJ, Hao SS - Sensors (Basel) (2015)

Bottom Line: The UAV flight system can be set to fly at a fixed and relatively low altitude to obtain the same resolution of ground images.A forward-looking camera is mounted on the upside of the aircraft's nose.Experimental results show that the proposed system enables UAVs to obtain terrain images at constant resolution, and to detect the relative altitude along the flight path.

View Article: PubMed Central - PubMed

Affiliation: Department of Electrical and Electronic Engineering, Chung Cheng Institute of Technology, National Defense University, Taoyuan 33551, Taiwan. 1040510304@ndu.edu.tw.

ABSTRACT
The fastest and most economical method of acquiring terrain images is aerial photography. The use of unmanned aerial vehicles (UAVs) has been investigated for this task. However, UAVs present a range of challenges such as flight altitude maintenance. This paper reports a method that combines skyline detection with a stereo vision algorithm to enable the flight altitude of UAVs to be maintained. A monocular camera is mounted on the downside of the aircraft's nose to collect continuous ground images, and the relative altitude is obtained via a stereo vision algorithm from the velocity of the UAV. Image detection is used to obtain terrain images, and to measure the relative altitude from the ground to the UAV. The UAV flight system can be set to fly at a fixed and relatively low altitude to obtain the same resolution of ground images. A forward-looking camera is mounted on the upside of the aircraft's nose. In combination with the skyline detection algorithm, this helps the aircraft to maintain a stable flight pattern. Experimental results show that the proposed system enables UAVs to obtain terrain images at constant resolution, and to detect the relative altitude along the flight path.

No MeSH data available.


Manual/automatic FCS architecture.
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sensors-15-16848-f002: Manual/automatic FCS architecture.

Mentions: Digital control signals are transformed by the detection results of the skyline detection and relative altitude detection algorithms. These digital control signals are subsequently converted to the analog control voltage of the RC by the D/A converter. A switch is installed on the RC to switch between manual and automatic flight modes. In manual flight mode of the RC, an operator controls the takeoff and landing of the aircraft, whereas in automatic flight mode, the FVP transmits real-time images to the GCS while executing skyline detection and relative altitude detection to analyze the control values for the pitch and roll angles. On determining the control value for the attitude, it can change the voltage signal using a proportional controller. The RC is controlled by the computer to modify the flight attitude so as to maintain the predefined relative altitude and ensure horizontal flight stability. The architecture of the manual/automatic flight system is depicted in Figure 2.


Monocular Vision System for Fixed Altitude Flight of Unmanned Aerial Vehicles.

Huang KL, Chiu CC, Chiu SY, Teng YJ, Hao SS - Sensors (Basel) (2015)

Manual/automatic FCS architecture.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4541911&req=5

sensors-15-16848-f002: Manual/automatic FCS architecture.
Mentions: Digital control signals are transformed by the detection results of the skyline detection and relative altitude detection algorithms. These digital control signals are subsequently converted to the analog control voltage of the RC by the D/A converter. A switch is installed on the RC to switch between manual and automatic flight modes. In manual flight mode of the RC, an operator controls the takeoff and landing of the aircraft, whereas in automatic flight mode, the FVP transmits real-time images to the GCS while executing skyline detection and relative altitude detection to analyze the control values for the pitch and roll angles. On determining the control value for the attitude, it can change the voltage signal using a proportional controller. The RC is controlled by the computer to modify the flight attitude so as to maintain the predefined relative altitude and ensure horizontal flight stability. The architecture of the manual/automatic flight system is depicted in Figure 2.

Bottom Line: The UAV flight system can be set to fly at a fixed and relatively low altitude to obtain the same resolution of ground images.A forward-looking camera is mounted on the upside of the aircraft's nose.Experimental results show that the proposed system enables UAVs to obtain terrain images at constant resolution, and to detect the relative altitude along the flight path.

View Article: PubMed Central - PubMed

Affiliation: Department of Electrical and Electronic Engineering, Chung Cheng Institute of Technology, National Defense University, Taoyuan 33551, Taiwan. 1040510304@ndu.edu.tw.

ABSTRACT
The fastest and most economical method of acquiring terrain images is aerial photography. The use of unmanned aerial vehicles (UAVs) has been investigated for this task. However, UAVs present a range of challenges such as flight altitude maintenance. This paper reports a method that combines skyline detection with a stereo vision algorithm to enable the flight altitude of UAVs to be maintained. A monocular camera is mounted on the downside of the aircraft's nose to collect continuous ground images, and the relative altitude is obtained via a stereo vision algorithm from the velocity of the UAV. Image detection is used to obtain terrain images, and to measure the relative altitude from the ground to the UAV. The UAV flight system can be set to fly at a fixed and relatively low altitude to obtain the same resolution of ground images. A forward-looking camera is mounted on the upside of the aircraft's nose. In combination with the skyline detection algorithm, this helps the aircraft to maintain a stable flight pattern. Experimental results show that the proposed system enables UAVs to obtain terrain images at constant resolution, and to detect the relative altitude along the flight path.

No MeSH data available.