Light-driven transport of plasmonic nanoparticles on demand

Laser traps provide contactless manipulation of plasmonic nanoparticles (NPs) boosting the development of numerous applications in science and technology. The known trapping configurations allow immobilizing and moving single NPs or assembling them, but they are not suitable for massive optical transport of NPs along arbitrary trajectories. Here, we address this challenging problem and demonstrate that it can be handled by exploiting phase gradients forces to both confine and propel the NPs. The developed optical manipulation tool allows for programmable transport routing of NPs to around, surround or impact on objects in the host environment. An additional advantage is that the proposed confinement mechanism works for off-resonant but also resonant NPs paving the way for transport with simultaneous heating, which is of interest for targeted drug delivery and nanolithography. These findings are highly relevant to many technological applications including micro/nano-fabrication, micro-robotics and biomedicine

Smooth Three-Dimensional Route Planning for Fixed-Wing Unmanned Aerial Vehicles With Double Continuous Curvature

This paper presents a smooth flight path planner for maneuvering in a 3D Euclidean space, which is based on two new space curves. The first one is called 'Elementary Clothoid-based 3D Curve (ECb3D)', which is built by concatenating two symmetric Clothoid-based 3D Curves (Cb3D). The combination of these curves allows to reach an arbitrary orientation in 3D Euclidean space. This new curve allows to generate continuous curvature and torsion profiles that start and finish with a null value, which means that they can be concatenated with other curves, such as straight segments, without generating discontinuities on those variables. The second curve is called 'Double Continuous Curvature 3D Curve (DCC3D)' which is built as a concatenation of three straight line segments and two ECb3D curves, allowing to reach an arbitrary configuration in position and orientation in the 3D Euclidean space without discontinuities in curvature and torsion. This trajectory is applied for autonomous path planning and navigation of unmanned aerial vehicles (UAVs) such as fixed-wing aircrafts. Finally, the results are validated on the FlightGear 2018 flight simulator with the UAV kadett 2400 platform

Smooth path planning with Pythagorean-hodoghraph spline curves geometric design and motion control

This thesis addresses two significative problems regarding autonomous systems, namely path and trajectory planning. Path planning deals with finding a suitable path from a start to a goal position by exploiting a given representation of the environment. Trajectory planning schemes govern the motion along the path by generating appropriate reference (path) points. We propose a two-step approach for the construction of planar smooth collision-free navigation paths. Obstacle avoidance techniques that rely on classical data structures are initially considered for the identification of piecewise linear paths that do not intersect with the obstacles of a given scenario. In the second step of the scheme we rely on spline interpolation algorithms with tension parameters to provide a smooth planar control strategy. In particular, we consider Pythagorean\u2013hodograph (PH) curves, since they provide an exact computation of fundamental geometric quantities. The vertices of the previously produced piecewise linear paths are interpolated by using a G1 or G2 interpolation scheme with tension based on PH splines. In both cases, a strategy based on the asymptotic analysis of the interpolation scheme is developed in order to get an automatic selection of the tension parameters. To completely describe the motion along the path we present a configurable trajectory planning strategy for the offline definition of time-dependent C2 piece-wise quintic feedrates. When PH spline curves are considered, the corresponding accurate and efficient CNC interpolator algorithms can be exploited

The Construction of Cubic Bezier Curve

The construction of Bezier curves is one of the curves that are commonly discussed in Computer-Aided Geometric Design (CAGD). This study focuses on cubic Bezier curve. The objectives in this study are to review the properties of cubic Bezier curve and construct the cubic Bezier curves. In this study, the expanding equations from the basis function of the curve is used to construct the cubic Bezier curve. Future researchers can expand the degree of the Bezier curves, which is more useful in Computer-Aided Design (CAD), CAGD and engineering. The next studies in Bezier curve are recommended as a contribution for further research

Optimal Path Planning Obstacle Avoidance of Robot Manipulator System using Bézier Curve

One of the problem that faced by engineers in most automated factories that require the need to move things from one place to another in an automated space with obstacles on its way the shortest route and the least time it takes to reach the goal. This paper presents an optimal path planning of 5DOF Lab-Volt 5250 robot manipulator joints and gripper to move from the given start point to the desired goal point without any collision with the obstacles whose boundaries are enveloped by a spherical shape, the size and the height of the obstacle is taken into account. The path planning approach presented is suggested in the robot joint space by using Bézier curve technique. The particle swarm optimization PSO method is used to get the optimal path with the shortest distance and the least time to move the end-effector from the initial point to the final point without hitting any obstacles which exist in the robot environment. This work is not  limited to theoretical studies or simulations, but several experiments cases were tested in different situations in a static environment known to test the robot's arm's ability to reach the desired target without hitting any obstacles with the shortest distance  and least time

Lunar Rover Motion Planning and Commands

Space exploration is moving forward and one of the topics currently being researched is mining. The objective of this thesis is to design and develop software for the auton- omous navigation of a wheeled rover that is being built for NASA’s Lunabotics Mining Competition. The motion control system is a crucial component of a planetary rover system and its implementation heavily depends on the chassis configuration. The configuration of the rover enables us to use three steering modes: Ackermann, Point- turn and Crab steering. The implementation takes advantages of all the modes and involves algorithms for path planning, path smoothing and path following. In addi- tion, the system offers a feature of automatic steering mode selection. The system can be tuned and controlled by the cross-platform application specifically developed for this purpose. The performance of the implemented system is analyzed by testing in a simulator with a realistic physics engine and 3D visualization capabilities. Our con- ducted tests confirm that the system is sufficient in the framework of the Lunabotics Mining Competition

Smooth path planning with Pythagorean-hodoghraph spline curves geometric design and motion control

This thesis addresses two significative problems regarding autonomous systems, namely path and trajectory planning. Path planning deals with finding a suitable path from a start to a goal position by exploiting a given representation of the environment. Trajectory planning schemes govern the motion along the path by generating appropriate reference (path) points. We propose a two-step approach for the construction of planar smooth collision-free navigation paths. Obstacle avoidance techniques that rely on classical data structures are initially considered for the identification of piecewise linear paths that do not intersect with the obstacles of a given scenario. In the second step of the scheme we rely on spline interpolation algorithms with tension parameters to provide a smooth planar control strategy. In particular, we consider Pythagorean–hodograph (PH) curves, since they provide an exact computation of fundamental geometric quantities. The vertices of the previously produced piecewise linear paths are interpolated by using a G1 or G2 interpolation scheme with tension based on PH splines. In both cases, a strategy based on the asymptotic analysis of the interpolation scheme is developed in order to get an automatic selection of the tension parameters. To completely describe the motion along the path we present a configurable trajectory planning strategy for the offline definition of time-dependent C2 piece-wise quintic feedrates. When PH spline curves are considered, the corresponding accurate and efficient CNC interpolator algorithms can be exploited

Bezier Curve Interpolation On Road Design

This research focuses on reconstructing the road curve by using Bezier curve fitting on a map. The usual way of constructing the Bezier curve is by using control points which can be very tedious. Since Bezier curves do not interpolate the control points, designers need to estimates the position of control points so that the curve fits well. In order to ease up the process, we will construct the Bezier curve by using the parameterization method where the data point information is required instead of the usual way of using control points. However, this method does not work on Bezier curve of high degree as the curves tend to become perturbed. One way of solving the problem is by using piecewise Bezier curve made up of several parameterized Bezier curves of lower degree. We propose a method to satisfy the continuity properties along this piecewise parameterized Bezier curve. The method had been implemented on two-dimensional model and spatial model. By using this method, we manage to construct a Bezier curve that can interpolate high number of data points while satisfying the continuity properties along the curve

Path planning for mobile robots in the real world: handling multiple objectives, hierarchical structures and partial information

Autonomous robots in real-world environments face a number of challenges even to accomplish apparently simple tasks like moving to a given location. We present four realistic scenarios in which robot navigation takes into account partial information, hierarchical structures, and multiple objectives. We start by discussing navigation in indoor environments shared with people, where routes are characterized by effort, risk, and social impact. Next, we improve navigation by computing optimal trajectories and implementing human-friendly local navigation behaviors. Finally, we move to outdoor environments, where robots rely on uncertain traversability estimations and need to account for the risk of getting stuck or having to change route