In this paper, we present two novel algorithms to realize a finite dimensional, linear time-invariant state-space model from input-output data. The algorithms have a number of common features. They are classified as one of the subspace model identification schemes, in that a major part of the identification problem consists of calculating specially structured subspaces of spaces defined by the input-output data. This structure is then exploited in the calculation of a realization. Another common feature is their algorithmic organization: an RQ factorization followed by a singular value decomposition and the solution of an overdetermined set (or sets) of equations. The schemes assume that the underlying system has an output-error structure and that a measurable input sequence is available. The latter characteristic indicates that both schemes are versions of the MIMO Output-Error State Space model identification (MOESP) approach. The first algorithm is denoted in particular as the (elementary MOESP scheme)...

Subspace model identification-Part 1. The output-error state-space model identification class of algorithms

Bridges and high mast luminaires (HMLs) are key components of transportation infrastructures. Effective inspection processes are crucial to maintain the structural integrity of these components. The most common approach for inspections is visual examination by trained and experienced inspectors. A proposed approach to assist inspectors during the visual inspection process is to use small unmanned aerial systems (sUAS) equipped with high-definition cameras to transmit video data of structural components in near real time. The use of sUAS as tools for structural inspections can significantly reduce costs and safety risks associated with inspectors and motorists, and improve the effectiveness and accuracy of structural health evaluations. Following a systems engineering approach, a proof-of-concept initial study was conducted to identify system limitations and gain insights into the expected usefulness of sUAS as tools for structural inspections. Extensive indoor controlled experiments using industrial fans were conducted to evaluate sUAS flight response in controlled wind conditions, to measure image quality in different flight scenarios, and to determine image quality in low-light conditions. Altitude, payload, and maneuverability tests were conducted to understand sUAS performance and limitation parameters related to their use for transportation infrastructure inspections. In full coordination with Florida Department of Transportation (FDOT), limited field tests were conducted to collect image data of underside bridge sections and HMLs. The collected images were of similar quality than those collected by inspectors during previous inspections. In addition, a basic sUAS flight training program was developed, and a preliminary cost analysis was conducted to estimate the cost for using sUAS as tools during inspections. Preliminary results showed potential cost savings in man-hours by using an sUAS approach instead of conventional methods. Overall, results provided evidence that significant benefits can be obtained from using sUAS during bridge and HML inspections. However, there still exist gaps that need to be addressed in order to use these aerial systems safely and effectively in practice. Various future research areas are identified to close these gaps and increase the general understanding of sUAS for structural inspections.

https://rosap.ntl.bts.gov/view/dot/29176/dot_29176_DS1.pdf

Proof of Concept for Using Unmanned Aerial Vehicles for High Mast Pole and Bridge Inspections

Scientific research and development on the control of autonomous airship have shown a significant growth in recent years. New applications appear in the areas such as freight carrier, advertising, monitoring, surveillance, transportation, military and scientific research. The control of Autonomous airship is a very important problem for the aerial robots research. In this paper, the previous research on the control of autonomous blimp is reviewed, Several popular control methods are categorized and discussed in detail. Then an intelligent navigation control method, reinforcement learning control, is introduced in the autonomous blimp which was used for 2007 UAV Outback Challenge. The future work on intelligent airship control is also outlined.

/pdf/control-of-autonomous-airship-5fwmqe64tt.pdf

Control of autonomous airship

Unmanned airships present an enormous potential for low-speed and low-altitude exploration applications. In order to develop a flight robot based on a small size unmanned remotely controlled airship, a flight and navigation system is presented in this paper. The hardware and software of the system are designed. As the kernel of the system, the flight control and navigation strategies are detailed. On the basis of the airship dynamic model, the architecture of the control system is presented, and the fuzzy controllers are employed and optimized using an improved genetic algorithm. Based on the airship model and the control and navigation strategies, the simulation studies of 3D path tracking problem are given and analyzed.

A flight control and navigation system of a small size unmanned airship

There are keen demands of robotic technologies in management of many kinds of emergencies. In this paper, we argue that unmanned airships present a unique potential in emergency management cycle, and their applications for surveillance, search and rescue, and communication are discussed. To make our lighter-than-air platform an autonomous airship with significant levels of autonomy for emergency management, the hardware infrastructure and software of the flight control system are designed and detailed. Based on a decoupled longitude and latitude dynamic model, the control architecture is developed, and a fuzzy control strategy is applied in mission path following problem. An application case of target searching using the autonomous airship is given and analyzed.

Unmanned airships for emergency management

Internet robotic systems have a different role in the use and development of aerial robots compared to that for ground robots. While for ground robotic vehicles, Internet is useful for remote operation or to make remote development, in aerial vehicles, in addition, the safety aspect must be considered very carefully. This paper addresses the requirements to the specific case of Internet aerial robots. It describes the conceptual and implementation aspects of an Internet-based software architecture for the AURORA unmanned autonomous airship project, showing its use in the different project phases.

B.G. Faria

Papers

Internet-based solutions in the development and operation of an unmanned robotic airship

Experimental identification of AURORA airship