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This article is devoted to investigation of the effectiveness of a method for automatic correction of the control program (ACCP) in practice to compensate for the elastic deformations occurring in turning nonrigid shafts. The relevance of the research is justified by a wide prevalence of this tool type in mechanical engineering, as well as the by the peculiarities of their turning at the modern CNC...
This paper proposes a method for maximizing the speed of the multilink manipulator gripper motion along a spatial trajectory with the current signal constraints and the input voltage of its servo drives factored in. We have studied various modes in which the synthetic system operates while processing the spatial end-of-arm motion trajectories of a varying curvature.
We consider a range estimation algorithm based on the time-of-arrival differences between multipath replicas of a signal transmitted by an anchor node of known location to a silent node that needs to localize itself. We consider the geometry of the problem in the simplified case of a constant sound speed profile (SSP), and argue that the more realistic case of a non-constant SSP can be still tackled...
Reconstructing normalized difference vegetation index (NDVI) time series datasets is essential for monitoring long-term changes of the terrestrial surface. Here, a temporal-spatial iteration (TSI) method was developed to estimate the NDVIs of contaminated MODIS13Q1 pixels based on reliable MODIS13Q1 data. NDVIs of contaminated pixels were firstly computed through linear interpolation of adjacent high-quality...
This paper describes the design, implementation and results of the image-based ego-motion estimation algorithm. As a source data the images captured from the bike platform are used. The device is supposed to be a part of a mobile mapping system prototype. Firstly the feature detection and matching is carried out providing the set of characteristic points in all images in the sequence. The 5-point...
The gesture recognition using motion capture data and depth sensors has recently drawn more attention in vision recognition. Currently most systems only classify dataset with a couple of dozens different actions. Moreover, feature extraction from the data is often computational complex. In this paper, we propose a novel system to recognize the actions from skeleton data with simple, but effective,...
In this paper, a new single sensor passive emitter localization approach is presented. The use of signal structure information allows TDOA-based localization with a single moving sensor node. A direct position estimation scheme is derived for the single sensor TDOA localization problem. The feasibility of the proposed method is shown in simulations. The position estimation accuracy of the single senor...
The registration of 3D laser scans is an important task in mapping applications. For the task of mapping with autonomous micro aerial vehicles (MAVs), we have developed a light-weight 3D laser scanner. Since the laser scanner is rotated quickly for fast omnidirectional obstacle perception, the acquired point clouds are particularly sparse and registration becomes challenging. In this paper, we present...
Motivated by the emergence of the Internet of Things (IoT), and by the importance that location information has on many complex systems scenarios, we propose a hybrid scheme for user positioning in an urban scenario. The system uses both a Global Navigation Satellite System (GNSS) and a Magnetic Positioning System (MPS). To maintain receiver complexity and cost at a minimum, the location scheme combines...
It is important to match vehicle GPS points onto a map. Many map-matching algorithms, which use heading, speed and position to complete the map-matching process, are not suitable for the low frequency GPS data. The distance between two adjacent GPS points in the low frequency GPS data can range from 500m to 1000m, and the vehicle can cross several streets. This paper puts forward a modified weight-based...
In this work a real-time indoor localisation system based on the Viterbi algorithm is developed. This Viterbi principle is used in combination with semantic data to improve the accuracy: i.e., the environment of the object that is being tracked and an adjustable maximum speed. The developed algorithm was verified by simulations and with experiments in a building-wide testbed for sensor and WiFi experiments...
We present a new approach for feature pooling in human action recognition. Instead of partitioning videos at predefined uniform intervals in a spatial-temporal volume as done with spatial pyramid matching, our method adaptively partitions in a pooling attribute space, defined by multiple trajectory-based cues. The pooling attributes include individual spatial and temporal coordinates of a trajectory,...
Human-action recognition through local spatio-temporal features have been widely applied because of their simplicity and its reasonable computational complexity. The most common method to represent such features is the well-known Bag-of-Words approach, which turns a Multiple-Instance Learning problem into a supervised learning one, which can be addressed by a standard classifier. In this paper, a...
In this paper, a new personal safety forewarning approach (PSFA) using GPS positioning and spatial analysis is presented. Specifically, we discussed the spatial topological relationships between the spatiotemporal objects related to personal safety. On that base, safety state is assessed through the calculation of a state matrix and then how to affirm the factors related to forewarning response is...
Time optimal trajectory planning under various hard physical constraints plays a significant role in simultaneously meeting the requirements on high productivity and high accuracy in the fields of both machining tools and robotics. In this paper, the problem of time optimal trajectory planning is first formulated, and then a novel back and forward check algorithm is proposed to solve the minimum time...
In this paper, the Zhang-gradient (ZG) method, which is a combination of Zhang dynamics (ZD) and gradient dynamics (GD) methods, is proposed for solving the tracking control problem of the multiple-input multiple-output (MIMO) system. Different from the traditional ZG method, GD is used additionally twice more in this paper to get through the derivation procedure. Moreover, each GD parameter is tunable...
In this paper an easy-to-use, wearable sensor system capable of deciphering upper-limb based functional tasks associated with stroke rehabilitation is introduced. Such a system can assist the therapist with monitoring a patient's progress during rehabilitation, and hence can increase the efficiency of the rehabilitation process. The developed system provides quantitative, real-time feedback of a user's...
There are many shape-similar gestures which cause errors in the process of hand gesture recognition. In this paper, a new method which can distinguish the similar gestures was proposed. The information of motion trajectory is captured by a leap motion in three-dimension space, and the orientation characteristics are quantified and coded as the feature. Then the Hidden Markov Model (HMM) algorithm...
Although many eddy identification approaches using drifter trajectories have been put forward, few studies have developed algorithms capable of recognizing complex looping structures in trajectories. Therefore, this paper presents a new method, called an improved automated loop-identifying scheme (AILIS), which is based on the ALIS algorithm proposed by Dong (Dong, 2011), to improve problems existing...
For validating the polarimetric & polarimetric-interferometric SAR modelling of vegetation, involved in biomass or surface moisture estimation at large scale, very high resolution polarimetric SAR acquisition on representative vegetated area could be useful. At resolution close to the wavelength such as 4 cm at X-band, the different scattering mechanisms can be spatially resolved. Several recent...
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