Feasibility of Warehouse Drone Adoption and Implementation

While aerial delivery drones capture headlines, the pace of adoption of drones in warehouses has shown the greatest acceleration. Warehousing constitutes 30% of the cost of logistics in the US. The rise of e-commerce, greater customer service demands of retail stores, and a shortage of skilled labor have intensified competition for efficient warehouse operations. This takes place during an era of shortening technology life cycles. This paper integrates several theoretical perspectives on technology diffusion and adoption to propose a framework to inform supply chain decision-makers on when to invest in new robotics technology

Nonlinear H ∞ optimal control scheme for an underwater vehicle with regional function formulation

A conventional region control technique cannot meet the demands for an accurate tracking performance in view of its inability to accommodate highly nonlinear system dynamics, imprecise hydrodynamic coefficients, and external disturbances. In this paper, a robust technique is presented for an Autonomous Underwater Vehicle (AUV) with region tracking function. Within this control scheme, nonlinear H∞ and region based control schemes are used. A Lyapunov-like function is presented for stability analysis of the proposed control law. Numerical simulations are presented to demonstrate the performance of the proposed tracking control of the AUV. It is shown that the proposed control law is robust against parameter uncertainties, external disturbances, and nonlinearities and it leads to uniform ultimate boundedness of the region tracking error

Kinematic and Dynamic Analysis of the 2-DOF Spherical Wrist of Orthoglide 5-axis

This paper deals with the kinematics and dynamics of a two degree of freedom spherical manipulator, the wrist of Orthoglide 5-axis. The latter is a parallel kinematics machine composed of two manipulators: i) the Orthoglide 3-axis; a three-dof translational parallel manipulator that belongs to the family of Delta robots, and ii) the Agile eye; a two-dof parallel spherical wrist. The geometric and inertial parameters used in the model are determined by means of a CAD software. The performance of the spherical wrist is emphasized by means of several test trajectories. The effects of machining and/or cutting forces and the length of the cutting tool on the dynamic performance of the wrist are also analyzed. Finally, a preliminary selection of the motors is proposed from the velocities and torques required by the actuators to carry out the test trajectories

RF communication between surface and underwater robotic swarms

In order for underwater robots to communicate with land and air based robots on an equal basis, high speed communications is required. If the robots are not to be tethered then wireless communications is the only possibility. Sonar communications is too slow. Unfortunately radio waves are rapidly attenuated under water due to phenomena such as skin depth. These experiments attempt to extend the range of underwater radio communications.<br /

The effect of surface treatment on composite interface, tensile properties and water absorption of suger palm fiber/polypropylene composites

The rising concern towards environmental issues besides the requirement for more flexible polymer-based material has led to increasing of interest in studying about green composite. Sugar palm fiber (SPF) is a versatile fiber plant employed with wide range of application such as in automotive, packaging and buildings construction. This research was aimed to study the effect of surface treatment on composite interface, tensile properties and water absorption of sugar palm fiber/polypropylene (SPFPP) composite by using different surface treatments such as silane (Si), atmospheric glow discharge plasma (Agd) and maleic anhydride (Ma). Silane treatment was carried out by using immersion method, the Agd plasma was conducted using polymerization and lastly polypropylene grafted maleic anhydride by using melting approach. The SPFPP composite was prepared by using injection moulding with fiber content var­ied from 10-30wt%. The effect of interface enhancement on morphology, mechanical properties and water uptakes of SPFPP composites were then investigated by using FfIR, FESEM, tensile test and water absorption test. Overall, the outcome shows that aJl types of surface treatments had improved the interface of SPFPP composite, thus improving its tensile properties compared to the benchmark untreated SPFPP (Ut­SPFPP) composites and polypropylene. The 30wt% Ma-SPFPP composite shows the highest improvement in tensile properties with 58% and 27% increase in the respective Young's Modulus and tensile strength value compared to Ut-SPFPP composite, while 10wt% Ma-SPFPP composite shows the smallest reduction in elongation compared to Neat PP. On the other hand, the 30wt% Si-SPFPP composite shows the lowest water absorption with 20% reduction respective to Ut-SPFPP composite. In conclusion, the surface treatments have proven succesfull in enhancing the natural fiber-polymer in­terface and improve the tensile properties of SPFPP composite with Ma-SPFPP shows the highest improvement, foJlowed by Agd-SPFPP and Si-SPFPP composites

The effect of surface treatment on composite interface, tensile properties and water absorption of suger palm fiber/polypropylene composites

The rising concern towards environmental issues besides the requirement for more flexible polymer-based material has led to increasing of interest in studying about green composite. Sugar palm fiber (SPF) is a versatile fiber plant employed with wide range of application such as in automotive, packaging and buildings construction. This research was aimed to study the effect of surface treatment on composite interface, tensile properties and water absorption of sugar palm fiber/polypropylene (SPFPP) composite by using different surface treatments such as silane (Si), atmospheric glow discharge plasma (Agd) and maleic anhydride (Ma). Silane treatment was carried out by using immersion method, the Agd plasma was conducted using polymerization and lastly polypropylene grafted maleic anhydride by using melting approach. The SPFPP composite was prepared by using injection moulding with fiber content var­ied from 10-30wt%. The effect of interface enhancement on morphology, mechanical properties and water uptakes of SPFPP composites were then investigated by using FfIR, FESEM, tensile test and water absorption test. Overall, the outcome shows that aJl types of surface treatments had improved the interface of SPFPP composite, thus improving its tensile properties compared to the benchmark untreated SPFPP (Ut­SPFPP) composites and polypropylene. The 30wt% Ma-SPFPP composite shows the highest improvement in tensile properties with 58% and 27% increase in the respective Young's Modulus and tensile strength value compared to Ut-SPFPP composite, while 10wt% Ma-SPFPP composite shows the smallest reduction in elongation compared to Neat PP. On the other hand, the 30wt% Si-SPFPP composite shows the lowest water absorption with 20% reduction respective to Ut-SPFPP composite. In conclusion, the surface treatments have proven succesfull in enhancing the natural fiber-polymer in­terface and improve the tensile properties of SPFPP composite with Ma-SPFPP shows the highest improvement, foJlowed by Agd-SPFPP and Si-SPFPP composites

Active Markov Information-Theoretic Path Planning for Robotic Environmental Sensing

Recent research in multi-robot exploration and mapping has focused on sampling environmental fields, which are typically modeled using the Gaussian process (GP). Existing information-theoretic exploration strategies for learning GP-based environmental field maps adopt the non-Markovian problem structure and consequently scale poorly with the length of history of observations. Hence, it becomes computationally impractical to use these strategies for in situ, real-time active sampling. To ease this computational burden, this paper presents a Markov-based approach to efficient information-theoretic path planning for active sampling of GP-based fields. We analyze the time complexity of solving the Markov-based path planning problem, and demonstrate analytically that it scales better than that of deriving the non-Markovian strategies with increasing length of planning horizon. For a class of exploration tasks called the transect sampling task, we provide theoretical guarantees on the active sampling performance of our Markov-based policy, from which ideal environmental field conditions and sampling task settings can be established to limit its performance degradation due to violation of the Markov assumption. Empirical evaluation on real-world temperature and plankton density field data shows that our Markov-based policy can generally achieve active sampling performance comparable to that of the widely-used non-Markovian greedy policies under less favorable realistic field conditions and task settings while enjoying significant computational gain over them.Comment: 10th International Conference on Autonomous Agents and Multiagent Systems (AAMAS 2011), Extended version with proofs, 11 page

Efficient motion planning for problems lacking optimal substructure

We consider the motion-planning problem of planning a collision-free path of a robot in the presence of risk zones. The robot is allowed to travel in these zones but is penalized in a super-linear fashion for consecutive accumulative time spent there. We suggest a natural cost function that balances path length and risk-exposure time. Specifically, we consider the discrete setting where we are given a graph, or a roadmap, and we wish to compute the minimal-cost path under this cost function. Interestingly, paths defined using our cost function do not have an optimal substructure. Namely, subpaths of an optimal path are not necessarily optimal. Thus, the Bellman condition is not satisfied and standard graph-search algorithms such as Dijkstra cannot be used. We present a path-finding algorithm, which can be seen as a natural generalization of Dijkstra's algorithm. Our algorithm runs in $O\left((n_B\cdot n) \log( n_B\cdot n) + n_B\cdot m\right)$ time, where~$n$ and $m$ are the number of vertices and edges of the graph, respectively, and $n_B$ is the number of intersections between edges and the boundary of the risk zone. We present simulations on robotic platforms demonstrating both the natural paths produced by our cost function and the computational efficiency of our algorithm

Systematic mapping literature review of mobile robotics competitions

This paper presents a systematic mapping literature review about the mobile robotics competitions that took place over the last few decades in order to obtain an overview of the main objectives, target public, challenges, technologies used and final application area to show how these competitions have been contributing to education. In the review we found 673 papers from 5 different databases and at the end of the process, 75 papers were classified to extract all the relevant information using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) method. More than 50 mobile robotics competitions were found and it was possible to analyze most of the competitions in detail in order to answer the research questions, finding the main goals, target public, challenges, technologies and application area, mainly in education.info:eu-repo/semantics/publishedVersio

Fluctuation characteristics and rolling control for an underactuated spherical underwater exploration robot

Compared with other underwater exploration robots, Spherical underwater robot has an outstanding advantage for the underwater exploration, whose spherical shell has the excellent resiliency to protect the internal electronic components. In addition, this steering resistance is very small to move flexibly. In this paper, a type of spherical underwater robot with the pendulums and a propeller was studied on moving at the water bottom in a rolling manner. The structure and force were analyzed to understand that the hydrodynamic force’s affection on the robot’s rolling at the water bottom. A mathematical model was established with the mass parameters and speeding parameters. The virtual simulation environment was established in Adams software. Furthermore, the coupling fluctuation characteristics of the speed, swing angle and the torque were studied by the simulation and the experiment in a pool. The study proved that this robot not only can use the propeller to move in water, but also can roll at the water bottom by driving the spherical shell. Especially, the result also can be obtained that the robot can roll at water bottom stably by increasing the pendulum mass and lowering the motor speed