uavvs component

Table of Contents

• Ports
  • desired (out)
• Services
  • enable_display (function)
  • close_display (function)
  • init_grabber (function)
  • init_detector (function)
  • init_camera (function)
  • init_servo (function)
  • log (function)
  • log_stop (function)
• Tasks
  • main

This component makes the drone detect and follow an AprilTag from the 36h11 family

Ports

desired (out)

Data structure struct ::or_rigid_body::state desired struct ::or::time::ts ts long sec long nsec boolean intrinsic optional< struct ::or::t3d::pos > pos double x double y double z optional< struct ::or::t3d::att > att double qw double qx double qy double qz optional< struct ::or::t3d::vel > vel double vx double vy double vz optional< struct ::or::t3d::avel > avel double wx double wy double wz optional< struct ::or::t3d::acc > acc double ax double ay double az optional< struct ::or::t3d::aacc > aacc double awx double awy double awz optional< struct ::or::t3d::jerk > jerk double jx double jy double jz optional< struct ::or::t3d::snap > snap double sx double sy double sz

Provides desired velocity

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Services

enable_display (function)

Inputs double frequency

Enable display with frequency image per second

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close_display (function)

Close the display

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init_grabber (function)

Inputs short device (default "0") short cam_index (default "0") short frame_rate (default "50") : in Hz boolean shutter (default "1") boolean gain (default "1")

Initialize grabber data structure and opens the grabber object The parameters are:

device :

• 0 if using FLIR cameras through FlyCapture SDK

• 1 if using cameras through OpenCV

cam_index : the index of the camera

frame_rate: Select the frame_rate of the camera (for FlyCapture)

shutter: auto or manual shutter (for FlyCapture)

gain: auto or manual gain (for FlyCapture)

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init_detector (function)

Inputs double tagSize double quad_decimate (default "2") double nThreads (default "4")

Initializes aprilTag detector

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init_camera (function)

Inputs double px double py double u0 double v0 double kud double kdu

Initialize camera parameters.

Note that this function should be called after calibrating the camera with ViSP calibration example.

This method initializes the camera with specific parameters using perspective projection with distortion model.

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init_servo (function)

Inputs double lambda_0 (default "0.5") : gain at 0 double lambda_inf (default "0.3") : gain at infinity double lambda_dot_0 (default "30") : slope at 0 double z_desired (default "1.25") : Desired distance to keep from tag double camera_pan double camera_pos[3]

Initialize visual servoing

camera_pos[3] is the position of camera frame’s origin in UAV’s frame

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log (function)

Inputs string<64> path (default "/tmp/test-visp.log") : Log file name unsigned long decimation (default "1") : Reduced logging frequency

Throws exception ::uavvs::e_sys short code string<128> what

Log data if visual servoing is initialized

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log_stop (function)

Stop logging

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Tasks

main

Context Frequency 20.0 Hz Updates port desired (out)

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