Conventional nonholonomic motion planning and control theories do not directly apply to “overconstrained vehicles,” such as the Sojourner vehicle of the Mars Pathfinder mission. This paper discusses some basic issues of motion planning and control for this potentially important class of mobile robots. A power dissipation approach is used to model the governing equations of overconstrained vehic...

In this paper, we present a method for synthesizing and analysing rhythmic character motions using signal processing methodologies, such as, the Fourier transform. While the Fourier transform has proven itself in many fields of engineering and computing for providing an uncumbersome and efficient method of representing signal or functional information in the frequency domain. As we show in this...

a user may n&d considerable tim;for finding the i'nformation he/she requires. This disadvantage may spoil the merit of video records. For this purpose, we previously reported that scenes of attention can be good indices for summarizing those videos[3]. The view from an HMC contains the central portion of the sight, and the camera's ego-motion represents the user's head motion. By estimating ego...

Differential flatness is a property which substantially reduces the difficulty involved in generating dynamically feasible trajectories for underactuated robotic systems. However, there is a large class of robotic systems that are not differentially flat, and an efficient method for computing dynamically feasible trajectories does not exist. In this paper we introduce a weaker but more general ...

In this paper, hybrid motion control and planning strategies for image constraints avoidance in robot visual servoing are presented. The proposed methods consist of a local switching control method and a global hybrid trajectory planning method. In local switching control, image local minima and image singularities can both be resolved by hybrid image-based and position-based visual servoing. T...

PURPOSE Subject motion is a major source of image degradation for functional MRI (fMRI), especially when using multishot sequences like three-dimensional (3D EPI). We present a hybrid radial-Cartesian 3D EPI trajectory enabling motion correction in k-space for functional MRI. METHODS The EPI "blades" of the 3D hybrid radial-Cartesian EPI sequence, called TURBINE, are rotated about the phase-e...

BACKGROUND The ideal surgical approach for cervical disk disease remains controversial, especially for multilevel cervical disease. The purpose of this study was to investigate the biomechanics of the cervical spine after 3-level hybrid surgery compared with 3-level anterior cervical discectomy and fusion (ACDF). MATERIAL AND METHODS Eighteen human cadaveric spines (C2-T1) were evaluated unde...

In this paper we introduce two techniques that can be used together to improve video coding performance. Firstly, block matching motion estimation with spatial transformation (BMST) is used to increase motion compression eeciency, and then motion compensated prediction (MCP) errors are encoded using a hybrid Fractal/DCT scheme. MCP error blocks are classiied according to their energy content an...

Color-based tracking is prone to failure in situations where visually similar targets are moving in close proximity to each other. To deal with the ambiguities in color information we propose an additional color-independent feature based on the target’s local motion, which is calculated from the optical flow induced by the target in consecutive images. By modifying a color-based particle filter...

In this paper, we propose a hierarchical three step search algorithm using pyramid hierarchy. Hierarchical Minkowski inequality is adopted to reduce the cost of the sum of absolute difference (SAD) computations. A top-town procedure is developed to search motion vectors hierarchically and the search pattern used in the well-known Three Step Search (TSS) is adopted. We also propose a hybrid moti...