control of robot locomotion profits from the use of pre-planned trajectories. This paper presents a way to generalize globally optimal and dynamically consistent trajectories for cyclic bipedal walking. A small task-s...
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control of robot locomotion profits from the use of pre-planned trajectories. This paper presents a way to generalize globally optimal and dynamically consistent trajectories for cyclic bipedal walking. A small task-space consisting of stride-length and step time is mapped to spline parameters which fully define the optimal joint space motion. The paper presents the impact of different machine learning algorithms for velocity and torque optimal trajectories with respect to optimality and feasibility. To demonstrate the usefulness of the trajectories, a control approach is presented that allows general walking including transitions between points in the task-space.
Actively cooled thermal protection system has great influence on the engine of a hypersonic vehicle, and it is significant to obtain the thermal and stress distribution in the system. So an analytic estimation and num...
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Actively cooled thermal protection system has great influence on the engine of a hypersonic vehicle, and it is significant to obtain the thermal and stress distribution in the system. So an analytic estimation and numerical modeling are performed in this paper to investigate the behavior of an actively cooled thermal protection system. The analytic estimation is based on the electric analogy method and finite element analysis（FEA） is applied to the numerical simulation. Temperature and stress distributions are obtained for the actively cooled channel walls with three kinds of nickel alloys with or with no thermal barrier coating（TBC）. The temperature of the channel wall with coating has no obvious difference from the one with no coating, but the stress with coating on the channel wall is much smaller than that with no coating. Inconel X-750 has the best characteristics among the three Ni-based materials due to its higher thermal conductivity, lower elasticity module and greater allowable stress. Analytic estimation and numerical modeling results are compared with each other and a reasonable agreement is obtained.
For cascaded systems, interactions among individually designed power subsystems may cause the instability of the whole system. Regulating the input impedance of the load converter is an effectively way to solve this p...
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ISBN:
(纸本)9781479985876
For cascaded systems, interactions among individually designed power subsystems may cause the instability of the whole system. Regulating the input impedance of the load converter is an effectively way to solve this problem, however, one big challenge of this method is how to consider the stability of cascaded system and the dynamic performance of load converter together. In light of this, this paper proposes a parallel-virtual-impedance (PVI) control strategy to improve the input impedance of the load converter. The proposed virtual impedance is in parallel with the load converter, via the proposed virtual impedances, the magnitude and phase of the input impedance of the load converter is modified only in a small range of frequency. As a result, this method not only solves the instability problem of the cascaded system, but also keeps a good dynamic performance for load converter. This paper discusses the concept, realization and design consideration of the proposed strategy in detail. Finally, a 100 W cascaded system, which consisting of an LC filter and a 48V-12V buck converter, is built to verify the correctness of the proposed methods 1 .
This paper presents an acquisition procedure and method of processing spatial images for face recognition with the use of a novel type of scanning device, namely mobile depth sensor Structure. Depth sensors, often cal...
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This paper presents an acquisition procedure and method of processing spatial images for face recognition with the use of a novel type of scanning device, namely mobile depth sensor Structure. Depth sensors, often called RGBD cameras, are able to deliver 3D images with a frame rate 30-60 frames per second, however they have relatively low resolution and a high level of noise. This kind of data is compared here with a high quality scans enrolled by the structural light scanner, for which the acquisition time is approximately 1.5 s for a single image, and which - because of its size - cannot be classified as a portable device. The purpose of this work was to find the method that will allow us to extract spatial features from mobile data sources analyzed here only in a static context. We transform the 3D data into local surface features and then into vectors of unified length by use of the Moving Least Squares method applied to a predefined grid of points on a reference cylinder. The feature matrices were calculated for various image features, and used in PCA analysis. Finally, the verification errors were calculated and compared to those obtained for stationary devices. The results show that single-image mobile sensor images lead to the results inferior to those of stationary sensors. However, we suggest a dynamic depth stream processing as the next step in the evolution of the described method. The presented results show that by including multi-frame processing into our method, it is likely to gain the accuracy similar to those obtained for a stationary device under controlled laboratory conditions.
It is difficult to be directly measured for some product quantities by sensors in industrial processes. There are many ways to use the relationship between process variables and quality variables to predict product qu...
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It is difficult to be directly measured for some product quantities by sensors in industrial processes. There are many ways to use the relationship between process variables and quality variables to predict product quality information indirectly, and then use it to fault diagnosis, such as partial least squares (PLS), total projection to latent structures (T-PLS) algorithm and so on. T-PLS decomposes the principal component space into two subspaces: Y-related subspace and Y-unrelated subspace, according to the prediction value of quality variables based on PLS. This paper presents an improved method of T-PLS. The improved method uses the ELM theory to predict quality, then the projection space is further decomposed based on the quality predict results of ELM. According to the comparison of ELM and PLS as well as the comparison of T-PLS and the new method in this paper, it proves the validity of the proposed method. Simulation verifies its properties.
The paper deals with the design of individual vehicle speed, taking into account the topographical characteristics of the road, the speed limit and the current traffic conditions. The look-ahead speed selection algori...
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The paper deals with the design of individual vehicle speed, taking into account the topographical characteristics of the road, the speed limit and the current traffic conditions. The look-ahead speed selection algorithm is implemented in microscopic traffic simulation environment V ISSIM u sing COM interface and MATLAB programming. The proposed look-ahead control is tested and analyzed on one of main transportation roads in Hungary namely between Tatabánya and Györ. The main novelty of the paper is the implementation of the look-ahead control in a realistic traffic environment, where the benefits of the method can be tested during different traffic conditions.
The article describes the idea of linking solutions from Brain computer Interfaces technology with augmented reality based on a Google device. A system composed of devices such as MindWave Mobile and Google Glass, whi...
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Short lived chest pain episodes of post PCI patients represent the most common clinical scenario treated in the Accidents and Emergency Room. Continuous ECG monitoring could substantially diminish such hospital admiss...
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Short lived chest pain episodes of post PCI patients represent the most common clinical scenario treated in the Accidents and Emergency Room. Continuous ECG monitoring could substantially diminish such hospital admissions and related ambulance calls. Delivering community based, easy-to-handle, easy to wear, real time electrocardiography systems is still a quest, despite the existence of electronic electrocardiography systems for several decades. The PATRIOT system serves this challenge via a 12-channel, easy to wear, easy to carry, mobile linked, miniaturized automatic ECG device and a Cloud platform. The system may deliver high quality electrocardiograms of a patient to medical personnel either on the spot or remotely both in a synchronous or asynchronous mode, enhancing autonomy, mobility, quality of life and safety of recently treated coronary artery disease patients.
This paper presents the methods used and experiences gained from teaching a digital system design course on a unified computerengineering learning platform. The learning platform is a result from the E2LP project who...
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This paper presents the methods used and experiences gained from teaching a digital system design course on a unified computerengineering learning platform. The learning platform is a result from the E2LP project whose main idea is to provide a unified platform which will cover a complete process for embedded computer systems learning. A modular approach is considered for skills practice through supporting individualization in learning. The main body of the platform is the base board with FPGA connected to a wide range of interfaces - audio, video, communication, memory and user I/O. Additionally the base board can be connected to one extension board via the standardized Mezzanine interface. Extension boards broaden the range of applications of the platform beyond digital system design and allow the platform to be used in the entire computerengineering curriculum. In addition to the technological approach, the use of cognitive theories on how people learn helps students achieve a stronger and smarter adaptation of the subject. One example course in digital system design is presented and experiences gained from applying it during one semester at University of Novi Sad are summarized. The results show the positive acceptance of the platform by students.
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