The major aim in search and rescue using mobile robots is to reach trapped survivors and to support rescue operations through the disaster environments. Our motivation is based on the fact that a search and rescue (SAR) robot can navigate within and penetrate a disaster area only if the area in question possesses connected voids Traversability or penetrability of a disaster area is a primary factor that guides the navigation of a search and rescue (SAR) robot, since it is highly desirable that the robot, without hitting a dead end or getting stuck, keeps its mobility for its primary task of reconnaissance and mapping when searching the highly unstructured environment We propose two novel guided prioritized exploration system: 1) percolation guided methodology where a percolator estimates the existence of connected voids in the upcoming yet unexplored region ahead of the robot so as to increase the efficiency of reconnaissance operation by the superior ability of the percolation guidance in speedy coverage of the area / 2) the hybrid exploration methodology that makes the percolation guided exploration collaborate with entropy based SLAM under a switching control dependent on either priority given to position accuracy or to map accuracy This second methodology has proven to combine the superiority of both methods so that the active SLAM becomes speedy, with high coverage rate of the area as well as accurate in localization.

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Inducement prizes-where cash rewards are given to motivate the attainment of targets--have been long used to encourage scientific research, develop technological innovations, or stimulate individuals, groups, and communities to accomplish diverse goals. Lately, prizes have increasingly attracted the attention of policy-makers, among others, due to their potential to induce path-breaking innovations and accomplish related goals. Academic research, however, has barely investigated these prizes in spite of their long history, recent popularity, and notable potential. This research investigates prizes and the means by which they induce innovation. It uses an empirical, multiple case-study methodology, a new model of innovation applied to prizes, and multiple data sources to investigate three cases of recent aerospace technology prizes: a main case study, the Google Lunar X Prize (GLXP) for robotic Moon exploration; and two pilot cases, the Ansari X Prize (AXP) for the first private reusable manned spacecraft and the Northrop Grumman Lunar Lander Challenge (NGLLC) for flights of reusable rocket-powered vehicles. The investigation unveils the dynamics of prizes and contributes a better understanding of their potential and disadvantages in a context in which more traditional mechanisms are used to induce innovation. This research shows that prizes are a more complex mechanism and their investigation requires analyzing entrant- and context-level factors generally not considered by the literature. Prizes complement and not replace patents and other incentive mechanisms. The incentives offered by prizes attract entrants with diverse characteristics, including unconventional entrants--individuals and organizations generally not involved with the prize technologies. Entrants are generally attracted by the non-monetary benefits of participation and the potential market value of the technologies involved in competitions. Many more volunteers, collaborators, and partners also participate indirectly and support official entries as they also perceive opportunities to accomplish their personal and organizational goals. The monetary reward is important to position the competition in the media and disseminate the idea of the prize. Prizes can induce increasing R&D activities and re-direct industry projects to target diverse technological goals, yet the evolution of prize competitions and quality of the technological outputs is generally difficult to anticipate. The overall organization of prize R&D activities and their outputs depend on entrant-level factors and can only be indirectly influenced by setting specific competition rules. The most remarkable characteristic of prize R&D activities is their interaction with fundraising efforts which, in some circumstances, may constrain the activities of entrants. Prizes can also induce innovation over and above what would have occurred anyway, yet their overall effect depends significantly on the characteristics of the prize entrants and the evolution of the context of the competition. The ability of prizes to induce innovation is larger when there are larger prize incentives, more significant technology gaps implicit in the prize challenge, and open-ended challenge definitions. To successfully induce technological breakthroughs, prizes may require complementary incentives (e.g. commitments to purchase technology) or support (e.g. seed funding.) Prizes are particularly appropriate to, for example, explore new, experimental methods and technologies that imply high-risk R&D; induce technological development to break critical technological barriers; accelerate technological development to achieve higher performance standards; and, accelerate diffusion, adoption, and/or commercialization of technologies. They involve, however, higher programmatic risks than other more traditional mechanisms and their routine use, and/or challenge definitions that overlap, can weaken the incentive power of the mechanism. Successful implementation of competitions requires many parameters to be properly set.

Aerocapture offers a near propellantless and quick method of orbit insertion at atmosphere bearing planetary destinations. Compared to conventional propulsive insertion, the primary advantage of using aerocapture is the savings in propellant mass which could be used to accommodate more useful payload. To protect the spacecraft from the aerodynamic heating during the maneuver, the spacecraft must be enclosed in a protective aeroshell or deployable drag device which also provides aerodynamic control authority to target the desired conditions at atmospheric exit. For inner planets such as Mars and Venus, aerocapture offers a very attractive option for inserting small satellites or constellations into very low circular orbits such as those used for imaging or radar observations. The large amount of propellant required for orbit insertion at outer planets such as Uranus and Neptune severely limits the useful payload mass that can delivered to orbit as well as the achievable flight time. For outer planet missions, aerocapture opens up an entirely new class of short time of flight trajectories which are infeasible with propulsive insertion. A systems framework for rapid conceptual design of aerocapture missions considering the interdependencies between various elements such as interplanetary trajectory and vehicle control performance for aerocapture is presented. The framework provides a step-by-step procedure to formulate an aerocapture mission starting from a set of mission objectives. At the core of the framework is the ``aerocapture feasibility chart", a graphical method to visualize the various constraints arising from control authority requirement, peak deceleration, stagnation-point peak heat rate, and total heat load as a function of vehicle aerodynamic performance and interplanetary arrival conditions. Aerocapture feasibility charts have been compiled for all atmosphere-bearing Solar System destinations for both lift and drag modulation control techniques. The framework is illustrated by its application to conceptual design of a Venus small satellite mission and a Flagship-class Neptune mission using heritage blunt-body aeroshells. The framework is implemented in the Aerocapture Mission Analysis Tool (AMAT), a free and open-source Python package, to enable scientists and mission designers perform rapid conceptual design of aerocapture missions. AMAT can also be used for rapid Entry, Descent, and Landing (EDL) studies for atmospheric probes and landers at any atmosphere-bearing destination.