Introduction

Use the MATLAB® Support Package for Parrot® Drones to control the drone and capture images from the FPV camera. A cascade object detector uses the Viola-Jones detection algorithm and a trained classification model for face detection. By default, the detector is configured to detect faces, but it can be used to detect other types of objects.

Required MathWorks Products

Prerequisites

CompleteGetting Started with MATLAB® Support Package for Parrot® Drones.

Required Hardware

To run this example you need:

Task 1 — Create a Connection to the Parrot Drone

Create aparrotobject.

parrotObj = parrot;

Task 2 — Create a Cascade Object Detector Instance

Create an instance of the cascade object detector to detect faces using the Viola-Jones algorithm.

detector = vision.CascadeObjectDetector;

Task 3 — Activate FPV Camera

Start the drone flight to activate the FPV camera. Move the drone up to sufficient height to capture faces.

takeoff(parrotObj); moveup(parrotObj,1);

Task 4 — Create a Connection to the Drone's FPV Camera

Use the parrot object from Task 1 to create the connection to the drone's FPV camera.

camObj = camera(parrotObj,'FPV');

Task 5 — Detect Faces While Traversing a Square Path

Detect faces while the drone moves forward for 2 seconds along the edge of a square path.

1推进无人机为默认的持续时间0.5 seconds for each forward step, ensuring a nonblocking behavior. This enables the drone to capture the image and detect faces while in motion.

2Capture a single frame from the drone's FPV camera.

3Input the image to the detector, which returns bounding boxes containing the detected objects. The detector performs multiscale object detection on the input image.

4Display the image with bounding boxes around faces and the title displaying the number of faces detected.

5Turn the drone by π/2 radians at each square vertex.

tOuter= tic;while(toc(tOuter)<=30 && parrotObj.BatteryLevel>20) tInner = tic;% Keep moving the drone for 2 seconds along each square path edgewhile(toc(tInner)<=2) moveforward(parrotObj);% Move the drone forward for default time of 0.5 seconds (nonblocking behaviour)picture = snapshot(camObj);% Capture image from drone's FPV camerabbox = detector(picture);% Detect faces in imagevideoOut = insertShape(picture,'Rectangle',bbox,'Color','r','LineWidth',3);% Insert bounding box into imageimshow(picture);% Show the picturetitle(sprintf(' %d face(s) detected ',size(bbox,1))); drawnow;endturn(parrotObj,deg2rad(90));%把无人机通过π/ 2弧度end

6Execute steps 1–5 for 30 seconds.

This example shows two faces detected by the drone's FPV camera.

Task 6 — Land the Drone

Land the drone.

land(parrotObj);

Task 7 — Clean Up

When finished clear the connection to the Parrot drone and the FPV camera.

clearparrotObj; clearcamObj;