A Model of Autonomous System for Scientific Experiments and Spacecraft Control for Deep Space Missions

Report published in the Proceedings of the National Conference on "Education and Research in the Information Society", Plovdiv, June, 2017The particularities of autonomous control system for deep space missions are described. A new approach for autonomous control system development is proposed and analyzed in details. Some models are analyzed and compared. The general formal model is based on the theory of communicating sequential processes (CSP). Methods for reconfiguration, verification and trace control are described. The software that is appropriate not only for the spacecraft flight path control but also for autonomous control of scientific apparatus operation and science experiments parameters is described. The software enables onboard scientific apparatus to autonomously detect and respond to science events Science algorithms, including onboard event detection, feature detection, change detection, and unusualness detection, are proposed to be used to analyze science data. Thus detecting features of scientific interest these algorithms are used to downlink only significant science data. These onboard science algorithms are inputs to onboard decision-making Replaner that modify the spacecraft observation plan to capture high value science events. This new observation plan is input for the Task execution subsystem of the Autonomous control system (ACS), able to adjust the plan to succeed despite run-time anomalies and uncertainties, and after it is executed by the ACS, which controls onboard scientific apparatus to enable an autonomous goal-directed exploration and data acquisition to maximize science return.Association for the Development of the Information Society, Institute of Mathematics and Informatics Bulgarian Academy of Sciences, Plovdiv University "Paisii Hilendarski

Some new ternary linear codes

Let an $[n,k,d]_q$ code be a linear code of length $n$, dimension $k$ and minimum Hamming distance $d$ over $GF(q)$. One of the most important problems in coding theory is to construct codes with optimal minimum distances. In this paper 22 new ternary linear codes are presented. Two of them are optimal. All new codes improve the respective lower bounds in [11]

Some new quasi-twisted ternary linear codes

Let $[n,k,d]_q$ code be a linear code of length $n$, dimension $k$ and minimum Hamming distance $d$ over $GF(q)$. One of the basic and most important problems in coding theory is to construct codes with best possible minimum distances. In this paper seven quasi-twisted ternary linear codes are constructed. These codes are new and improve the best known lower bounds on the minimum distance in [6]

Performance evaluation of data delivery approaches for wireless sensor networks

AbstractWireless sensor networks are expected to revolutionize our abilities in sensing and controlling the physical environment. Power conservation is a primary research concern for these networks, due to the limited energy resources of the sensor nodes. In this paper we study the data delivery approaches, suitable for hierarchical cluster based wireless sensor networks. A radio energy dissipation model is used to evaluate the energy, needed for both intra-cluster and inter-cluster communication. Based on the results we analyze the performance of various combined data delivery approaches. Additionally we study the impact of the base station location and the number of sensor nodes on the energy dissipation and the network lifetime

New minimum distance bounds for linear codes over GF(5)

AbstractLet [n,k,d]q-codes be linear codes of length n, dimension k and minimum Hamming distance d over GF(q). In this paper, 32 new codes over GF(5) are constructed and the nonexistence of 51 codes is proved

An Approach towards Balanced Energy Consumption in Hierarchical Cluster-based Wireless Sensor Networks

In this paper we investigate the mechanisms for organization of the clusters in wireless sensor networks (WSN). After the short introduction to these systems we present the communication architecture and the energy dissipation model, which are used for the hierarchical cluster-based WSN. In the third section of the paper we analyze the current widely used process for organization of the clusters and we outline its main disadvantages. Later we present an approach for balanced consumption of the energy by the sensor motes, and then we propose a modification to this approach. In the next section we present and analyze the results of a series of simulation experiments, which we have conducted with the proposed approach, and then we compare these results with the ones obtained from the simulation experiments, which are conducted with the other presented approaches

Innovative development of a flying robot with a flexible manipulator for aerial manipulations

This paper presents an innovative development of a flying robot or an aerial robot, with a flexible manipulator, called the Dexterous Aerial Robotic System (DFTS), for aerial manipulations, especially for inspections and reparations of various structures such as wind turbines, power lines and open gas pipelines, decorations and painting of high industrial chimneys and walls of high buildings, as well as transport and delivery of courier shipments, relocation and manipulation of assemblies and units in inaccessible or dangerous environments. The proposed DFTS consists of two independent but interconnected systems or functional units, which have two main separate functions respectively, including a basic carrying function, and a precise positioning and stabilization function. The system with a basic carrying function is actually the main flying system, the un-manned aerial vehicle (UAV); it is remotely controlled and piloted. Meanwhile, the aerial manipulation platform, called the vertical take-off and landing platform VTOL, which is an active flying platform with 6 degrees of freedom (DOF) is used for positioning and stabilization; and it is attached to the UAV via the soft link. With the use of a long soft link, the problems which are caused by the air turbulent flows generated by the UAV are minimized, and the aerial manipulations of objects are safely controlled and operated. The VTOL which is equipped with a grasping mechanism was successfully developed, prototyped and tested. The experimental results showed that, the developed VTOL can self-stabilize with the inclination angle of being up to 8 degrees

Development of a smart system for early detection of forest fires based on unmanned aerial vehicles

The naturally occurring wildfires and the people-related forest fires are events, which in many cases have significant impact on the environment, the wildlife and the human population. The most devastating among these events usually start in unpopulated remote areas, which are difficult to inspect or are not constantly being monitored or observed. This gives the local small-sized fires enough time to evolve into full-scale wide-area disasters, which in turn makes their suppression and extinguishing very difficult. In this paper, we present an autonomous system for early detection of forest fires, named THEASIS-M. The presented system represents a solution that is based on a combination of innovative technologies, including computer vision algorithms, artificial intelligence and unmanned aerial vehicles. In the first part of the study, we provide an overview on the present applications of the UAVs in the forestry domain. The paper then introduces the general architecture of the THEASIS-M system and its components. The system itself is fully autonomous and is based on several different types of UAVs, including a fixed-wing drone, which provides the overall forest monitoring capabilities of the proposed solution, and a rotary-wing UAV that is used for confirmation and monitoring of the detected fire event. The widely used technologies for computer vision and image processing, which are used for the detection of fire and smoke in the real-time video streams sent from the UAVs to the ground control station, are highlighted in the next section of this study. Finally, the experimental tests and demonstrations of the proposed THEASIS-M system are presented and briefly discussed

Measurement of the B0s→μ+μ− Branching Fraction and Effective Lifetime and Search for B0→μ+μ− Decays

A search for the rare decays Bs0→μ+μ- and B0→μ+μ- is performed at the LHCb experiment using data collected in pp collisions corresponding to a total integrated luminosity of 4.4  fb-1. An excess of Bs0→μ+μ- decays is observed with a significance of 7.8 standard deviations, representing the first observation of this decay in a single experiment. The branching fraction is measured to be B(Bs0→μ+μ-)=(3.0±0.6-0.2+0.3)×10-9, where the first uncertainty is statistical and the second systematic. The first measurement of the Bs0→μ+μ- effective lifetime, τ(Bs0→μ+μ-)=2.04±0.44±0.05  ps, is reported. No significant excess of B0→μ+μ- decays is found, and a 95% confidence level upper limit, B(B0→μ+μ-)<3.4×10-10, is determined. All results are in agreement with the standard model expectations.A search for the rare decays $B^0_s\to\mu^+\mu^-$ and $B^0\to\mu^+\mu^-$ is performed at the LHCb experiment using data collected in $pp$ collisions corresponding to a total integrated luminosity of 4.4 fb$^{-1}$. An excess of $B^0_s\to\mu^+\mu^-$ decays is observed with a significance of 7.8 standard deviations, representing the first observation of this decay in a single experiment. The branching fraction is measured to be ${\cal B}(B^0_s\to\mu^+\mu^-)=\left(3.0\pm 0.6^{+0.3}_{-0.2}\right)\times 10^{-9}$, where the first uncertainty is statistical and the second systematic. The first measurement of the $B^0_s\to\mu^+\mu^-$ effective lifetime, $\tau(B^0_s\to\mu^+\mu^-)=2.04\pm 0.44\pm 0.05$ ps, is reported. No significant excess of $B^0\to\mu^+\mu^-$ decays is found and a 95 % confidence level upper limit, ${\cal B}(B^0\to\mu^+\mu^-)<3.4\times 10^{-10}$, is determined. All results are in agreement with the Standard Model expectations