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The subject of this paper is the system scanning and 3-D model determination. The main purpose of the proposed system is a 3-D model reconstruction of agricultural products. The purpose of these models is the determination of examined product dimensions and calculation of other relevant parameters such as volume or shape. In addition to physical characteristics, the system allows the analysis of the product colors which are one of the most important parameters. The paper describes details of the pinhole camera model that is used during calibration and scanning, which allows the removal of image distortions resulting from the imperfection of optics (lens distortion). Calibration procedures are presented with one camera as well as with stereo cameras. It is possible to determine the point in real space and to create a model of the observed object by using stereo triangulation and camera model parameters. Finally, we show the results of the system operation as well as possible improvements which can increase performance.

Portal scraper is machine widely used for bulk material supply of industrial facilities. Its performance is usually highly dependable on the ability of human operators since it relies on manual operation for some of its most sensitive functions. Fully automated portal scrapers with appropriate solutions for critical operation situations can significantly contribute to increasing the reliability of bulk material supply to the production process. Because of that, the analysis of portal scraper functionality and recognition of the main points of concern for its proper operation are presented in the paper as a base for the development of fully automated control solution. The time critical operations were identified and appropriate algorithms were developed for the reduction of time spent in unproductive motion.

Abstract Background Functional electrical stimulation (FES) applied via transcutaneous electrodes is a common rehabilitation technique for assisting grasp in patients with central nervous system lesions. To improve the stimulation effectiveness of conventional FES, we introduce multi-pad electrodes and a new stimulation paradigm. Methods The new FES system comprises an electrode composed of small pads that can be activated individually. This electrode allows the targeting of motoneurons that activate synergistic muscles and produce a functional movement. The new stimulation paradigm allows asynchronous activation of motoneurons and provides controlled spatial distribution of the electrical charge that is delivered to the motoneurons. We developed an automated technique for the determination of the preferred electrode based on a cost function that considers the required movement of the fingers and the stabilization of the wrist joint. The data used within the cost function come from a sensorized garment that is easy to implement and does not require calibration. The design of the system also includes the possibility for fine-tuning and adaptation with a manually controllable interface. Results The device was tested on three stroke patients. The results show that the multi-pad electrodes provide the desired level of selectivity and can be used for generating a functional grasp. The results also show that the procedure, when performed on a specific user, results in the preferred electrode configuration characteristics for that patient. The findings from this study are of importance for the application of transcutaneous stimulation in the clinical and home environments.