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An important step for the classification of plants in organic farming is the separation of the objects. In our approach a 3D camera will be used for this task. One problem is that most of the available 3D sensors are not suitable due to their bad resolution, low-speed and high costs. The Kinect II is an affordable alternative but designed for another workspace. In this paper it is shown why a 3D sensor is required for the separation of objects in organic farming and how the modification of a Kinect II 3D camera increases the range resolution to solve the given problem.

In order to increase the measurement speed of pattern projection-based three-dimensional (3-D) sensors, in 2014, we introduced the so-called array projector which allows pattern projection at several 1,000 fps. As the patterns are switched by switching on and off the light sources of multiple slide projectors, each pattern originates from a different projection center. This may lead to a 3-D point deviation when measuring glossy objects. In this contribution, we theoretically and experimentally investigate the dependence of this deviation on the measurement object's reflective properties. Furthermore, we propose a procedure for compensating for this deviation.

This paper describes the implementation of displaying real-time processed LiDAR 3D data in a DVE pilot assistance system. The goal is to display to the pilot a comprehensive image of the surrounding world without misleading or cluttering information. 3D data which can be attributed, i.e. classified, to terrain or predefined obstacle classes is depicted differently from data belonging to elevated objects which could not be classified. Display techniques may be different for head-down and head-up displays to avoid cluttering of the outside view in the latter case. While terrain is shown as shaded surfaces with grid structures or as grid structures alone, respectively, classified obstacles are typically displayed with obstacle symbols only. Data from objects elevated above ground are displayed as shaded 3D points in space. In addition the displayed 3D points are accumulated over a certain time frame allowing on the one hand side a cohesive structure being displayed and on the other hand displaying moving objects correctly. In addition color coding or texturing can be applied based on known terrain features like land use.

Objective: The aim of this study is to assess the accuracy of Procrustes analysis(PA)to compute a mid-sagittal plane(MSP)of three-dimensional(3D) facial data. Methods: Facial surface data from 30 subjects were acquired by a Face Scan optical 3D sensor. Using the data, 30 asymmetrical facial images with a true MSP for control purpose were constructed using the original facial image. The MSPs of the 30 images are then computed using Procrustes analysis. The angle between the true-MSP and the MSP obtained using the PA, and the asymmetry index serve as measures of assessing the accuracy of the Procrustes analysis to compute the MSP of 3D facial data. Results: The mean value and the standard deviation of the angle between the true-MSP and the PA-MSP are 0.62° and 0.49° respectively. The t-test for paired groups is used to assess the differences between the two MSPs in the facial asymmetry index and P values of smaller than 0.05 are considered significant(t=0.783,p=0.440). Conclusions: There are no significant differences between the PA-MSP and the true-MSP in terms of the asymmetry index of the 30 subjects. Thus the Procrustes analysis can be used to compute the MSP of 3D facial data with a significant degree of accuracy.

A new, handheld 3D surface scanner was developed especially for underwater use until a diving depth of about 40 meters. Additionally, the sensor is suitable for the outdoor use under bad weather circumstance like splashing water, wind, and bad illumination conditions. The optical components of the sensor are two cameras and one projector. The measurement field is about 250 mm x 200 mm. The depth resolution is about 50 μm and the lateral resolution is approximately 150 μm. The weight of the scanner is about 10 kg. The housing was produced of synthetic powder using a 3D printing technique. The measurement time for one scan is between a third and a half second. The computer for measurement control and data analysis is already integrated into the housing of the scanner. A display on the backside presents the results of each measurement graphically for a real-time evaluation of the user during the recording of the measurement data.

The crone seedlings have unstable form and it is hard to handle. In order to transplant crone seedlings automatically, the functions of 3D-shape recognition and force control of grippers are indispensable. We have introduced the new handling technology which combines the 3D-mesurement using the relative stereo method and gripping method by gripping stroke control for high elasticity forceps structure. In this gripping method, the gripping force is controlled according to the shoot diameter which is measured by 3d-mesurment of relative stereo method. The experimental crone seedlings transplant system using the new handling technique has been shown.

A new depth-from-defocus type co-axial 3-D sensor is proposed that permits shade-free absolute 3-D shape measurement from the contrast information of a frequency-multiplexed single fringe pattern. The Fourier transform method is used for spatial frequency demultiplexing and extracting the fringe contrast. Experimental results are presented that demonstrate the validity of the principle.

The application of an active vision 3D sensor is described for the development and control of an autonomous intelligent robot cell for the disassembling of end-of-life-vehicle components. The research and development work was done concurrently by three European development teams at different locations. During this phase, the virtual environment was distributed on the local development platforms of these teams. Intermediate development results and 3D sensor data were exchanged through network communication to be mutually tested and verified. The physical environment of the disassembling cell demonstrator and its sensor systems is currently being integrated at the BIBA institute.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

An algorithm is presented to relatively align a 3D sensor and a 2D sensor measuring range and azimuth. The alignment is done using common targets that are tracked by both sensors. The algorithm estimates and removes sensor biases and sensor frame orientation errors. For illustrative purposes, the alignment algorithm is applies to simulated track data.