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In this paper, a tracking system with multi-sensors is presented, in which a sub-orbit USV (unmanned space vehicle) of wave-rider shape is tracked by a TDRS (Tracking and Data Relay Satellite) and ground stations. Because of high lift-drag ratio and maneuverability, the vehicle, once is used in reentering purpose, a complicated trajectory will be produced and cause big challenges for tracking facilities...
In this paper, a position domain PD control for contour tracking is proposed to improve the contour tracking performance. To develop the position domain control, one motion is selected as a master (reference) motion and all other motions are viewed as slave motions. The reference motion is sampled equidistantly in the position domain and used as an independent variable. A dynamic model for the slave...
A common problem with modern manufacturing processes that utilize high speed machining is the ability to accurately track a contour of the end-effector. Various control methods have been developed to increase axial tracking performance in the time domain. This paper discusses a new control method developed in the position domain, and the developed position domain control is applied to a 3-axis CNC...
It's well known that measured or estimated uncertainty information is absolutely beneficial to design robust controller. However, few researches have been conducted on that due to the difficulties of obtaining uncertainty information. Most recently, development of observation/estimation and measurement techniques (especially for nonlinear systems) make it possible to get full or partial uncertainty...
In this paper a discrete-time sliding mode control for the trajectory tracking problem of wheeled mobile robots is presented. The wheeled mobile robot (WMR) taken into account was PowerBot. PowerBot is a mobile platform with two differential driving wheels (2DW) and two balancing caster wheels. It is an automated guided vehicle specially designed and equipped for autonomous, intelligent delivery and...
This paper presented a medical robot system for celiac minimally invasive surgery (MIS). A new mechanism was proposed to realize two-dimensional remote center of motion (RCM) with simple structure, and surgical instruments without coupled motion were designed, which greatly improved the performance and manipulability of the robot. The system worked in master-slave control mode. According to the configurations...
Bevel-tip steerable needles are widely used in modern minimally invasive percutaneous procedures to reach specific positions inside the body. In this paper, we design a shortest path with the least control effort for such a steerable needle, giving the start and the goal positions with or without obstacles. We assume that the environment is static and the motion of the needle is counted based on the...
Assistive knee brace is a species of wearable lower extremity exoskeletons. Such assistive equipment can enhance people's strength and provide desired locomotion to have advantages over wheelchairs, which are commonly used for patients with mobility disorders. However, the integration between the assistive knee brace and the user is challenging as inaccurate alignments may adversely affect the biomechanics...
This paper presents an experiment of using external magnetic field to implement the actuation of wireless capsule endoscope with open-loop control strategy. We use two pairs of rectangle coils to generate rotary magnetic field. The capsule with a permanent magnet rotates along with the magnetic field. With the help of the whirl on its surface, the capsule can move in a certain direction. From the...
At present, the application of Capsule endoscopy (CE) faces some extremely important issues, e.g., image quality and field of view, which causing difficulties for doctors to make an accurate diagnosis. It's a technical difficulty to acquire wide-angle internal intestinal image under the volume restrictions of CE. In this paper, a simple and practical design of CE lens aimed to clearer and wider-angle...
High resolution broadband source direction of arrival (DOA) estimation is a challenge problem in acoustic array signal processing. While the compressive sensing (CS) is a recent theory exploring the signal sparsity representation, which has been received considerable attentions in various research areas. In this paper, we study on the DOA estimation under CS framework (DOA-CS) making use of the spatial...
In this paper, a CDMA acoustic communication system for multiuser based on hardware platform is developed. The sound card in the computer with sound box and microphone is used as the energy transduction to accomplish acoustic communication. For the hardware part, DS18B20 is taken for example as the data source to generate the original signals and MAX232 chip is adopted to connect the MCU to the RS-232...
In this paper, an improved high-resolution ESPRIT algorithm for direction of arrival (DOA) estimation of coherent signals is proposed, which is based on a new SVD method, the MSVD-ESPRIT algorithm for short. The main idea is to construct a matrix with the maximum eigenvector according to certain rules, then fix this matrix and get two signal subspaces by singular value decomposition; at the last we...
The stochastic resonance (SR), taking advantage of the noise instead of suppressing it, has been proved to be a novel way to enhance detection, amplification, and transmission of weak signals. The classical SR requires small parameters (e.g., the driving frequency is much lower than 1 Hz) according to the adiabatic approximation. Nevertheless, large parameter problems may usually be involved in real...
Electrocardiogram (ECG) monitoring and the P-QRS-T waveform and rhythmic analysis are essential for clinicians to understand the vital cardiac physiological functions of the subjects with cardiac problems or heavier cardiac load. This is becoming more significant as seniors are getting popular who often need clinical cardiovascular attention. We propose a new approach to ECG acquisition with the capability...
In video surveillance system, a large number of video measurements would increase network load and degrade control performance, and make data storage a difficult task. Hence, how to adaptively reduce the data quantity and preserve the essential information of video data becomes an important research issue. In this paper, an adaptive adjustment based on temporal similarity and spatial importance is...
We propose to explore a novel tracking system for human tracking in thermal catadioptric omnidirectional (TCO) vision, which is able to realize the surveillance in all-weather and wide field of view conditions. In contrast, previous human tracking system mainly focuses on tracking in conventional imaging system. In this paper, the proposed tracking method adopts the classification posterior probability...
This paper proposes a content based method to improve image search results from Google search engine. The images returned by Google are used to learn a statistical binary classifier for measuring their relevance to the query. The learning process includes three stages. In the first stage, positive and negative examples are selected from the images by using k-medoids clustering technique. In the second...
This paper presents a fast and efficient image registration algorithm for UAV image sequence. The proposed algorithm consists of three main steps: feature extraction, feature point tracking, and homography matrix estimation. According to the comparison with different feature points, we choose the KLT feature and track them during the consecutive images. With the correct tracked feature points, the...
It is one of the most important technologies for lunar exploration to reconstruct three-dimensional terrain and generate digital terrain map by the stereo vision. The algorithm of generating digital terrain map based on binocular vision system is studied in this paper. Polar rectification and stereo match are made for image before three-dimensional reconstruction. According to the characteristics...
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