Innovative software solutions for subsea positionings

<p>Improving operational efficiency is a recurring challenge for subsea operations. Throughout the life of a field, from construction up to decommissioning, several subsea vehicles will be deployed to cover various tasks to perform underwater observations. An ROV or AUV assigned to a specific task will require multiple positioning sensors (LBL, USBL, INS…) to complete its mission. Defining the “good enough” subsea positioning strategy, i.e. to ensure a minimum accuracy without compromise on safety, can be a complex exercise. For instance, an overestimation of the LBL transponders required will directly induce vessel time and finally costly operations. On the other hand, a certain level of positioning redundancy may be requested for a vehicle operating close to a subsea asset in production.</p><p>To ease the design and monitoring of a subsea vehicle navigation, iXblue has developed an integrated solution. Not only has the company broadened its product range with the new intelligent Canopus LBL Transponder and the new generation Ramses transceiver, but with Delph Subsea Positioning Software, iXblue now provides a complete integrated solution for subsea positioning that goes a step further by bringing significant efficiency. Divided in 4 modules (LBL Array Planning, Navigation Simulation, Operations, DelphINS) with an intuitive user interface, Delph Subsea Positioning (DSP) is an integrated software suite for the preparation, the operation and the post-processing of iXblue positioning devices (USBL, LBL and INS).</p>

Simulation Model of Crowd Evacuation Navigation in a Multi-Obstacle Environment

The simulation of a crowd evacuating public buildings can be an important reference in planning the layout of buildings and formulating evacuation strategies. This paper proposes an agent-based crowd model; a crowd evacuation navigation simulation model is proposed for the multi-obstacle environment. We introduce the concept of navigation factor to describe the proximity of the navigation point to the exit. An algorithm for creating navigation points in multi-obstacle environment is proposed along with the global navigation and local navigation control algorithms of the crowd. We construct a crowd evacuation simulation prototype system with different simulation scenes using the scene editor. We conduct the crowd evacuation simulation experiment in the multi-obstacle scene, recording and analyzing the relevant experimental data. The simulation prototype system can be used to derive the evacuation time of the crowd and analyze the evacuation behavior of the crowd. It is expected to provide a visual deduction method for crowd management in an evacuation emergency.

An Extensible Orthopedic Wire Navigation Simulation Platform

The demand for simulation-based skills training in orthopedics is steadily growing. Wire navigation, or the ability to use 2D images to place an implant through a specified path in bone, is an area of training that has been difficult to simulate given its reliance on radiation-based fluoroscopy. Our group previously presented on the development of a wire navigation simulator for a hip fracture module. In this paper, we present a new methodology for extending the simulator to other surgical applications of wire navigation. As an example, this paper focuses on the development of an iliosacral wire navigation simulator. We define three criteria that must be met to adapt the underlying technology to new areas of wire navigation; surgical working volume, system precision, and tactile feedback. The hypothesis being that techniques, which fall within the surgical working volume of the simulator, demand a precision less than or equal to what the simulator can provide, and that require the tactile feedback offered through simulated bone can be adopted into the wire navigation module and accepted as a valid simulator for the surgeons using it. Using these design parameters, the simulator was successfully configured to simulate the task of drilling a wire for an iliosacral screw. Residents at the University of Iowa successfully used this new module with minimal technical errors during use.

Navigation Simulation of a Mecanum Wheel Mobile Robot Based on an Improved A* Algorithm in Unity3D

Computer simulation is an effective means for the research of robot navigation algorithms. In order to implement real-time, three-dimensional, and visual navigation algorithm simulation, a method of algorithm simulation based on secondary development of Unity3D is proposed. With this method, a virtual robot prototype can be created quickly with the imported 3D robot model, virtual joints, and virtual sensors, and then the navigation simulation can be carried out using the virtual prototype with the algorithm script in the virtual environment. Firstly, the scripts of the virtual revolute joint, virtual LiDAR sensors, and terrain environment are written. Secondly, the A* algorithm is improved for navigation in unknown 3D space. Thirdly, taking the Mecanum wheel mobile robot as an example, the 3D robot model is imported into Unity3D, and the virtual joint, sensor, and navigation algorithm scripts are added to the model. Then, the navigation is simulated in static and dynamic environments using a virtual prototype. Finally, the navigation tests of the physical robot are carried out in the physical environment, and the test trajectory is compared with the simulation trajectory. The simulation and test results validate the algorithm simulation method based on the redevelopment of Unity3d, showing that it is feasible, efficient, and flexible.