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This paper proposes a novel pose system for mobile robots, which can provide cheap and robust solution for pose estimation. Its pose estimation approach is based on at least two optical sensors. The pose system also presents a method for system calibration to improve accuracy. There are several advantages with respect to this system: (1) the measurement from the optical sensors is insensitive to slipping and crawling; (2) this pose estimation system is independent from the kinematics of the robot; (3) compared to incremental encoders, our system is a low-cost and flexible solution for indoor mobile robots. Some simulations have been done to validate our system. [ABSTRACT FROM AUTHOR]

Mobile manipulation is a key capability to many robotic applications in construction, space, underwater, nuclear plant and home services. Dynamic modeling and trajectory control for a holonomic omnidirectional mobile manipulator are principle problems for mobile manipulation, and are presented in this paper. Considered the redundantly-actuated property of omnidirectional mobile platform, the kinematic model of the whole mobile manipulator is presented. Then, an integrated dynamic model for the system is developed by the kinematic model and Lagrangian formalism. According to the dynamic model, a modified inverse dynamic control is addressed to track the trajectories of the mobile platform and end-effector simultaneously. Then, the simulations results show the effectiveness of the proposed modeling and control approach. [ABSTRACT FROM AUTHOR]

High speed networks with high delays present a unique environment where TCP can not efficiently utilize the full bandwidth. In this paper, we present a simple and novel Time Based Congestion Control scheme (TBCC for short) that alleviates RTT unfairness while supporting TCP friendliness and bandwidth scalability. We provide the general framework for TBCC protocol modifications. Then, using a simplified design, we illustrate the scalability of TBCC for improving the efficiency, without sacrificing the fairness of TCP. We assess the RTT unfairness of TBCC and show that the RTT unfairness of TBCC can be firmly guaranteed to be no worse than that of unmodified TCP. Compared with similar protocols such as HSTCP and STCP, TBCC can guarantee the bandwidth scalability and achieve better fairness. The flexible framework of TBCC provides a whole class of design options for improving the performance of TCP in high speed networks. [ABSTRACT FROM AUTHOR]

Recently, many new flow control mechanisms derived from classic Kelly model are proposed to solve network congestion problem. They perform well in stability, fairness or robustness. However, most of their convergence rates are linear since in classic Kelly model, link price is only positive. In addition, some need to introduce extra packet header to get price information. This paper presents a novel flow control model based on Kelly model in which the link price can be negative to improve the convergence rate. Further, The proposed model uses two bits of ECN field to feed back price instead of introducing new packet header data. Thus it can implement flow control scheme achieving exponential convergence in traditional TCP/IP datagram format. NS2 simulation results show that our model can keep fairness and asymptotic stability with more rapid convergence rate. [ABSTRACT FROM AUTHOR]

To overcome the deficiency of Support Vector Machine (SVM) for regression, dynamic ε-SVM method was proposed. To establish precise mathematical models, a new modeling method was introduced, combining self-organizing feature map (SOFM) with the dynamic ε-SVM. Firstly, SOFM was used as a clustering algorithm to partition the whole input space into several disjointed regions; then, the dynamic ε-SVM modeled for these partitioned regions. This method was illustrated by modeling penicillin fermentation process with plant field data. Results show that the method achieves significant improvement in generalization performance compared with other methods based on SVM. [ABSTRACT FROM AUTHOR]

A genetic algorithm (GA) based composite sliding mode fuzzy control (CSMFC) approach is proposed for the double-pendulum-type overhead crane (DPTOC). The overhead crane exhibits double-pendulum dynamics because of the large-mass hook and the payload volume. Its nonlinear dynamic model is built using Lagrangian method. Through defining a composite sliding mode function, the proposed control approach greatly reduces the complexity to design a controller for complex underactuated systems. The control system stability is analyzed for DPTOC. Real-valued GA is used to optimize the parameters of CSMFC to improve the performance of control system. Simulation results illustrate the complexity of DPTOC and the validity of proposed control algorithm. [ABSTRACT FROM AUTHOR]