Dual-camera-based motion estimation method of light stream detection device for aircraft

Abstract

The invention relates to a dual-camera-based motion estimation method of a light stream detection device for an aircraft. First, the light stream detection device for the aircraft, which consists of a forward-looking camera and a down-looking camera, is used for collecting forward-looking images and down-looking images in real time, and the light stream values, which are represented by a first formula shown in the description and a second formula shown in the description, of corresponding multiple characteristic points between the current frames and the last frames of the forward-looking images and the down-looking images are calculated respectively; secondly, the angular speed of the aircraft is calculated by utilizing the distribution characteristics of the translational light streams of the forward-looking images and the decoupling thoughts of the light streams, and an attitude angle is updated; thirdly, the translational light streams of the down-looking images are obtained by utilizing the obtained angular speed and the second formula shown in the description. By utilizing the obtained attitude angle, each characteristic point is deeply represented to be the function of the terrain clearance of the aircraft; a novel translational motion estimation equation is established; the speed v of the aircraft is solved by using a UKF (unscented Kalman filter). Finally, the six-degree-of-freedom motion estimation of the aircraft is gained. The dual-camera-based motion estimation method of the light stream detection device for the aircraft is applicable to the navigation of indoor, low-altitude or deep-space aircraft such as a mars exploration aircraft. The forward-looking camera to which the dual-camera-based motion estimation method of the light stream detection device for the aircraft relates can be also used for completing the calculation of an attack angle and a sideslip angle and other navigation tasks of evading an obstruction, and the like.

Description

technical field [0001] The invention relates to a motion estimation method of an aircraft optical flow detection device based on a dual camera, which realizes real-time motion estimation of six degrees of freedom of an aircraft by relying only on visual sensors, and is suitable for navigation of indoor, low-altitude or deep-space vehicles such as Mars exploration aircraft. Background technique [0002] Due to the limitation of the cost, size and weight of sensors, visual navigation has become an important development direction of UAV navigation. "Optical flow" refers to a series of flowing image light intensity information formed on the retina of the human eye or the compound eye of an insect due to the relative movement between the observer and the external environment. The sports field reflects the three-dimensional motion in the real scene. The optical flow field is the projection of the sports field on the two-dimensional image. The optical flow contains rich navigation ...

AI Technical Summary

Problems solved by technology

[0004] In addition, the existing motion estimation equation uses the depth of each feature point as a state quantity, and every time the optical flow value of a feature point is added as a quantity measurement, the system will increase one dimension, and the calculation amount is large

In short, the existing motion estimation method based on a single downward-looking camera has low accuracy, and the motion estimation method based on the assumption of level flight has relatively large limitations, and the calculation amount of the motion estimation equation needs to be reduced

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