This web page presents different videos of the three dimensional path follower. As UAL integrates the robot simulator Gazebo, the developed path follower may be tested easily in simulation. All simulation here presented have been performed based on the same UAV model, a simulated autopilot based on the PX4 firmware and assuming a maximum speed of 1 m/s. First simulations use a cruising speed of 1 m/s and a look ahead distance of 1 meter to see how the generator mode affects on the behavior of the path follower. After that, a wrong look ahead setup is forced to see how the path follower performance decreases.
Generator mode 0Generator mode 0
The generator at mode 0 results on a linear interpolated path.
Mean = 0.088 (m) | Maximum = 0.454 (m) | Minimum = 0.000 (m) | Variance = 0.015 (m) | Standard deviation = 0.122 (m)
Generator mode 1
The generator at mode 1 results on a cubic interpolated path. This mode is a step between mode 0 and mode 1, having a less curve-shaped path with smoothed corners.
Mean = 0.086 (m) | Maximum = 0.399 (m) | Minimum = 0.002 (m) | Variance = 0.009 (m) | Standard deviation = 0.095 (m)
Generator mode 2
The generator at mode 2 results on a cubic interpolated path.
Mean = 0.064 (m) | Maximum = 0.238 (m) | Minimum = 0.002 (m) | Variance = 0.001 (m) | Standard deviation = 0.038 (m)
Wrong look ahead setup
Try different values on simulation several times is recommended before going to fly in the real world because these values directly depend on the input desired path. The videos presented shows that the UAV can oscillate about the path if a short look ahead distance is settled. On the other hand, if the user sets a large look ahead distance the UAV will cut corners because the UAV tries to turn towards each new virtual point.
Short look ahead distance:
Large look ahead distance: