Outdoor experiments with a luxmeter

2021 ◽  
Vol 56 (5) ◽  
pp. 055029
Author(s):  
Ana Gostinčar Blagotinšek
Keyword(s):  
1972 ◽  
Vol 6 (3) ◽  
pp. 197-207 ◽  
Author(s):  
J.A.M. Barynin ◽  
M.J.G. Wilson
Keyword(s):  

2021 ◽  
Author(s):  
Dengqing Tang ◽  
Lincheng Shen ◽  
Xiaojiao Xiang ◽  
Han Zhou ◽  
Tianjiang Hu

<p>We propose a learning-type anchors-driven real-time pose estimation method for the autolanding fixed-wing unmanned aerial vehicle (UAV). The proposed method enables online tracking of both position and attitude by the ground stereo vision system in the Global Navigation Satellite System denied environments. A pipeline of convolutional neural network (CNN)-based UAV anchors detection and anchors-driven UAV pose estimation are employed. To realize robust and accurate anchors detection, we design and implement a Block-CNN architecture to reduce the impact of the outliers. With the basis of the anchors, monocular and stereo vision-based filters are established to update the UAV position and attitude. To expand the training dataset without extra outdoor experiments, we develop a parallel system containing the outdoor and simulated systems with the same configuration. Simulated and outdoor experiments are performed to demonstrate the remarkable pose estimation accuracy improvement compared with the conventional Perspective-N-Points solution. In addition, the experiments also validate the feasibility of the proposed architecture and algorithm in terms of the accuracy and real-time capability requirements for fixed-wing autolanding UAVs.</p>


The article describes the main development and testing aspects of an emergency braking function for an autonomous vehicle. The purpose of this function is to prevent the vehicle from collisions with obstacles, either stationary or moving. An algorithm is proposed to calculate deceleration for the automated braking, which takes into account the distance to the obstacle and velocities of both the vehicle and the obstacle. In addition, the algorithm adapts to deviations from the required deceleration, which are inevitable in the real-world practice due to external and internal disturbances and unaccounted dynamics of the vehicle and its systems. The algorithm was implemented as a part of the vehicle’s mathematical model. Simulations were conducted, which allowed to verify algorithm’s operability and tentatively select the system parameters providing satisfactory braking performance of the vehicle. The braking function elaborated by means of modeling then was connected to the solenoid braking controller of the experimental autonomous vehicle using a real-time prototyping technology. In order to estimate operability and calibrate parameters of the function, outdoor experiments were conducted at a test track. A good consistency was observed between the test results and simulation results. The test results have proven correct operation of the emergency braking function, acceptable braking performance of the vehicle provided by this function, and its capability of preventing collisions.


1990 ◽  
Vol 4 (4) ◽  
pp. 849-854 ◽  
Author(s):  
John W. Leif ◽  
Ervin A. Oelke

Outdoor experiments were conducted at two locations in Minnesota to characterize the growth, development, and vegetative reproduction potential of giant burreed grown with and without wild rice. Giant burreed growth was influenced by environment more than the presence of wild rice. Shoots emerged from corms 2 to 3 wk after planting (WAP), and continued throughout the growing season. Giant burreed attained a maximum height of 135 cm with an average 36 shoots/plant. Rhizome production started 4 to 6 WAP, and continued throughout the growing season. Corm formation at the base of shoots started 8 WAP and continued throughout the growing season. Rhizomes grew to a maximum cumulative length of 2500 cm/plant spreading in all directions and produced up to 250 buds/plant. Corm and rhizome bud viability was 15 and 10%, respectively. These data suggest that giant burreed grown in wild rice should be controlled by 2 to 3 wk after emergence to prevent vegetative reproduction.


2019 ◽  
Vol 34 (12) ◽  
pp. 40-48 ◽  
Author(s):  
Roland Oechslin ◽  
Sebastian Wieland ◽  
Sebastian Hinrichsen ◽  
Uwe Aulenbacher ◽  
Peter Wellig

2004 ◽  
Author(s):  
Kohzo Homma ◽  
Hirokimi Shingu ◽  
Hiromichi Yamamoto ◽  
Hirohisa Kurosaki

2016 ◽  
Vol 110 (5) ◽  
pp. 401-402 ◽  
Author(s):  
Daniel J. Blumenthal ◽  
Stephen V. Musolino

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