The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Use of robots is rising in process applications where robots need to interact with parts using tools. Representative examples can be cleaning, polishing, grinding, etc. These tasks can be non-repetitive in nature and the physics-based models of the task performances are unknown for new materials and tools. In order to reduce operation cost and time, the robot needs to identify and optimize the trajectory...
Motion planning for multi-target autonomous search requires efficiently gathering as much information over an area as possible with an imperfect sensor. In disaster scenarios and contested environments the spatial connectivity may unexpectedly change (due to aftershock, avalanche, flood, building collapse, adversary movements, etc.) and the flight envelope may evolve as a known function of time to...
We present planning algorithms for cleaning stains on a curved object. Removing the stain may require multiple reorientations and repositions of the object and some portions of the stain may require multiple cleaning passes. The experimental setup involves two robot arms. The first arm immobilizes the object. The second arm moves the cleaning tool. The algorithm analyzes the stain and determines the...
In this paper, we present an approach to perform automatic robotic cleaning of deformable objects with unknown stiffness characteristics. A bimanual robot setup is used, where one arm holds the part to be cleaned, while the other holds the cleaning tool. The robot maintains an approximate model of the deformation behavior of each part it interacts with and incrementally improves the model as it performs...
In this paper, we consider the problem of guarding a valuable naval asset from a highly maneuverable threat via the use of autonomous unmanned surface vehicles (USVs) as dynamic obstacles. The objective of the defending agent is to maximize the amount of time it takes an intruder boat to enter the restricted area. Here we introduce a set of active blocking strategies which allow the defender to influence...
Quadruped locomotion offers significant advantages over wheeled locomotion for small mobile robots operating in challenging terrain. Central pattern generators (CPGs), as found in the neural circuitry of many animals, may be used to generate joint trajectories for quadruped robots. However, basic CPG-based trajectories do not explicitly consider ground contact constraints, a particular concern during...
We consider the problem of learning user preferences over robot trajectories for environments rich in objects and humans. This is challenging because the criterion defining a good trajectory varies with users, tasks and interactions in the environment. We represent trajectory preferences using a cost function that the robot learns and uses it to generate good trajectories in new environments. We design...
Despite being around for almost two decades, foot-mounted inertial navigation only has gotten a limited spread. Contributing factors to this are lack of suitable hardware platforms and difficult system integration. As a solution to this, we present an open-source wireless foot-mounted inertial navigation module with an intuitive and significantly simplified dead reckoning interface. The interface...
We introduce a model-predictive trajectory planning algorithm for unmanned surface vehicles (USVs) operating in congested civilian traffic. The planner reasons about the availability of contingency maneuvers needed in case of any of the civilian vessels breaches the International Regulations for the Prevention of Collisions at Sea (COLREGs). Our exploratory study indicated that implementing the envisioned...
We present a look-ahead based trajectory planning algorithm for computation of dynamically feasible trajectories for Unmanned Sea Surface Vehicles (USSV) operating in high seas states. The algorithm combines A* based heuristic search and locally bounded optimal planning under motion uncertainty using a variation of the minimax game-tree search. This allows the algorithm to compute trajectories that...
Traveling-wave tubes (TWTs), used in civil and defence applications, require high power and multi-octave bandwidth rather than high efficiency and hence just a single stage depressed collector is sufficient. However, TWT used in space applications necessarily has to have very high efficiency rather than wide bandwidth. A user friendly multi-stage depressed (MDC) collector design code in MATLAB for...
Non-conventional 3-stage collector geometry has been designed using EGUN code for high efficiency applications deviating from typical 4-stage depressed collector. Efficiency of this collector is very much similar to 4-stage collector with reduced dimensions, weight, etc, which are very important if such collector is to be used for space applications. Such collector also reduces the complexity of electronic...
Conventional microwave tubes generally use cylindrical electron beam coaxial to RF interaction circuit for generation or amplification of microwave signals. Many performance limitations these tubes in respect of band width, efficiency, voltage break have been addressed by emerging multi-beam technology which uses several low perveance electron beams in place of single beam used in conventional tubes...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.