Advantages of 3D time-of-flight range imaging cameras in machine vision applications

Machine vision using image processing of traditional intensity images is in wide spread use. In many situations environmental conditions or object colours or shades cannot be controlled, leading to difficulties in correctly processing the images and requiring complicated processing algorithms. Many of these complications can be avoided by using range image data, instead of intensity data. This is because range image data represents the physical properties of object location and shape, practically independently of object colour or shading. The advantages of range image processing are presented, along with three example applications that show how robust machine vision results can be obtained with relatively simple range image processing in real-time applications

Hardiness Scripts: High‐Achieving African American Boys In A Chicago Charter School Navigating Community Violence And School

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/122441/1/jcop21791.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/122441/2/jcop21791_am.pd

Acridid ecology in the sugarcane agro-ecosystem in the Zululand region of KwaZulu-Natal, South Africa

CITATION: Bam, A., Addison, P. & Conlong, D. 2020. Acridid ecology in the sugarcane agro-ecosystem in the Zululand region of KwaZulu-Natal, South Africa. Journal of Orthoptera Research, 29(1):9–16, doi:10.3897/jor.29.34626.The original publication is available at https://jor.pensoft.netGrasshoppers and locusts are well known crop and pasture pests throughout the world. Periodically they cause extensive damage to large areas of crops and grazing lands, which often exacerbate food shortage issues in many countries. In South Africa, acridid outbreaks rarely reach economic proportions, but in sugarcane plantations, localized outbreaks of native acridid species have been reported for the last eight years with increasing frequency and intensity in certain areas. This study was undertaken from May 2012 to May 2013 to identify the economically important acridid species in the sugarcane agroecosystem in these outbreak areas, to monitor seasonal activity patterns, to assess sampling methods, and to determine the pest status of the major species through damage ratings. Five acridid species of particular importance were identified: Nomadacris septemfasciata (Serville), Petamella prosternalis (Karny), Ornithacris cyanea (Stoll), Cataloipus zuluensis Sjötedt, and Cyrtacanthacris aeruginosa (Stoll). All species are univoltine. Petamella prosternalis was the most abundant species and exhibited a winter egg diapause, while N. septemfasciata, the second most abundant species, exhibited a winter reproductive diapause. Petamella prosternalis and N. septemfasciata were significantly correlated with the damage-rating index, suggesting that these two species were responsible for most of the feeding damage found on sugarcane. This study, for the first time, identified the acridid species complex causing damage to sugarcane in the Zululand area of KwaZulu-Natal, South Africa, and documented their population characteristics and related damage. These data are important information on which to base sound integrated pest management strategies.SASRINational Research Foundation of South Africahttps://jor.pensoft.net/article/34626/element/8/64680//Publisher's versio

Calibration and control of a robot arm using a range imaging camera

Time of flight range imaging is an emerging technology that has numerous applications in machine vision. In this paper we cover the use of a commercial time of flight range imaging camera for calibrating a robotic arm. We do this by identifying retro-reflective targets attached to the arm, and centroiding on calibrated spatial data, which allows precise measurement of three dimensional target locations. The robotic arm is an inexpensive model that does not have positional feedback, so a series of movements are performed to calibrate the servos signals to the physical position of the arm. The calibration showed a good linear response between the control signal and servo angles. The calibration procedure also provided a transformation between the camera and arm coordinate systems. Inverse kinematic control was then used to position the arm. The range camera could also be used to identify objects in the scene. With the object location now known in the arm's coordinate system (transformed from the camera's coordinate system) the arm was able to move allowing it to grasp the object