Ultrawideband (UWB) based localization has the potential to be used in a variety of applications due to its high accuracy. For robust and high performance in real environment, the most challenging issue is the detection and mitigation of noise from non-line-of-sight (NLOS) signals. Current researches use channel state information, particle or Kalman filter, and statistics based approaches for the NLOS noise detection and mitigation. These solutions show high accuracy in some applications; however, they need additional hardware and work in static environment only. We propose an NLOS mitigation algorithm that does not need any additional hardware andworks in dynamic environment with mobile obstacles. The main idea of the algorithm are to estimate the NLOS bias by repetitively comparing the intersection of the hyperbolas with intersections of circles. The proposed approach is tested for Decawave UWB testbed. Experimental results show that the proposed scheme works well in different dynamic scenarios as compared to the localization scheme without NLOS noise mitigation.

In collective intelligent robots, communication capability is considered as a key feature to decide how to design the collaboration policy. A cooperative routing robot system is suggested to maintain the communication capability in between human and a robot and an algorithm to establish a seamless global communication is proposed. Generating the radio signal map is suggested to estimate an area where communication is possible. If the robots only move in the area, they can prevent the disconnection of communication in different radio environments. The proposed algorithm is composed of two steps. At the first step, Extended Kalman Filter is designed to estimate state of the radio environments. Then, the communication link a radio signal map is generated using k-NN(Nearest Neighbors)algorithm. Experiments with routing robots and sensing system verify our proposed system and algorithm are valid in real environment.

In collective intelligent robots, communication capability is considered as a key feature to decide how to design the collaboration policy. A cooperative routing robot system is suggested to maintain the communication capability in between human and robots and an algorithm to establish a seamless global communication is proposed. In this paper, implementation of seamless communication between human and the robots using cooperative routing robots is shown in real environment.

A middleware model named ROAFTS (Real-time Object-oriented Adaptive Fault Tolerance Support) has been evolving in the UCI DREAM Lab. over the past decade as the core of a reliable execution engine model for fault-tolerant (FT) real-time (RT) distributed computing (DC) applications. It is meant to be an integration of various mechanisms for fault detection and recovery in a form that meshes well with high-level RT DC object-/component- based programming, in particular, TMO (Time-triggered Message-triggered Object) programming. Using ROAFTS as a backbone and low-layer middleware, we developed a model and a skeleton implementation for FT DC middleware providing efficient FT execution services for component-based home network applications. Capabilities for management of home information processing devices, including health monitoring of home devices, reconfiguration of device connections, and servicing queries on device status, were added to ROAFTS. Those additions were first designed as a network of high-level RT DC components, i.e., TMOs. Then the TMO network was extended into an FT TMO network by applying the replication scheme called the PSTR (Primary-Shadow TMO Replication) scheme and incorporating a component responsible for reconfiguring TMO replicas. This extension of ROAFTS is called ROAFTS-HNE (Home Network Extension) and its architecture is presented here. In addition, during the development of the ROAFTS-HNE model, we formulated a new approach for applying the PSTR scheme to RT DC components supported by ROAFTS. Finally, evaluations of the recovery times of a prototype implementation have been conducted.