Proactive kinodynamic planning using the extended social force model and human motion prediction in urban environments

Trabajo presentado al IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS 2014), celebrado en Chicago, Illinois (US) del 14 al 18 de septiembre.This paper presents a novel approach for robot navigation in crowded urban environments where people and objects are moving simultaneously while a robot is navigating. Avoiding moving obstacles at their corresponding precise moment motivates the use of a robotic planner satisfying both dynamic and nonholonomic constraints, also referred as kynodynamic constraints. We present a proactive navigation approach with respect its environment, in the sense that the robot calculates the reaction produced by its actions and provides the minimum impact on nearby pedestrians. As a consequence, the proposed planner integrates seamlessly planning and prediction and calculates a complete motion prediction of the scene for each robot propagation. Making use of the Extended Social Force Model (ESFM) allows an enormous simplification for both the prediction model and the planning system under differential constraints. Simulations and real experiments have been carried out to demonstrate the success of the proactive kinodynamic planner.Work supported by the Spanish Ministry of Science and Innovation under project Rob Task Coop (DPI2010-17112).Peer Reviewe

Comparative analysis of human motion trajectory prediction using minimum variance curvature

Presentado al 6th HRI celebrado en Lausanne (Suiza) del 8 al 11 de marzo de 2011.The prediction of human motion intention is a key issue towards intelligent human robot interaction and robot navigation. In this work we present a comparative study of several prediction functions that are based on the minimum curvature variance from the current position to all the potential destination points, that means, the points that are relevant for people motion intention. The proposed predictor computes, at each interval of time, the trajectory from the present to the destination positions, and makes a prediction of the human motion at each interval of time using only the criterion of minimum curvature variation. The method has been validated in the Edinburgh Informatics Forum Pedestrian database.This research was conducted at the Institut de Robotica i Informatica Industrial (CSIC-UPC). It was partially supported by CICYT projects DPI2007-61452 and Ingenio Consolider CSD2007-018.Peer Reviewe

Behavior estimation for a complete framework for human motion prediction in crowded environments

Presentado al ICRA 2014 celebrado en Hong Kong del 31 de mayo al 7 de junio.In the present work, we propose and validate a complete probabilistic framework for human motion prediction in urban or social environments. Additionally, we formulate a powerful and useful tool: the human motion behavior estimator. Three different basic behaviors have been detected: Aware, Balanced and Unaware. Our approach is based on the Social Force Model (SFM) and the intentionality prediction BHMIP. The main contribution of the present work is to make use of the behavior estimator for formulating a reliable prediction framework of human trajectories under the influence of dynamic crowds, robots, and in general any moving obstacle. Accordingly, we have demonstrated the great performance of our long-term prediction algorithm, in real scenarios, comparing to other prediction methods.Work supported by the Spanish Ministry of Science and Innovation under project RobTaskCoop (DPI2010-17112).Peer Reviewe

Multi-objective cost-to-go functions on robot navigation in dynamic environments

Trabajo presentado a la International Conference on Intelligent Robots and Systems, celebrada en Hamburgo (Alemania) del 28 de septiembre al 2 de octubre de 2015.In our previous work we introduced the Anticipative Kinodynamic Planning (AKP): a robot navigation algorithm in dynamic urban environments that seeks to minimize its disruption to nearby pedestrians. In the present paper, we maintain all the advantages of the AKP, and we overcome the previous limitations by presenting novel contributions to our approach. Firstly, we present a multi-objective cost function to consider different and independent criteria and a well-posed procedure to build a joint cost function in order to select the best path. Then, we improve the construction of the planner tree by introducing a cost-to-go function that will be shown to outperform a classical Euclidean distance approach. In order to achieve real time calculations, we have used a steering heuristic that dramatically speeds up the process. Plenty of simulations and real experiments have been carried out to demonstrate the success of the AKP.This work was supported by the Spanish Ministry of Science and Innovation project DPI2013-42458-PPeer Reviewe

Best Axes Composition Extended: Multiple Gyroscopes and Accelerometers Data Fusion to Reduce Systematic Error

Multiple rigidly attached Inertial Measurement Unit (IMU) sensors provide a richer flow of data compared to a single IMU. State-of-the-art methods follow a probabilistic model of IMU measurements based on the random nature of errors combined under a Bayesian framework. However, affordable low-grade IMUs, in addition, suffer from systematic errors due to their imperfections not covered by their corresponding probabilistic model. In this paper, we propose a method, the Best Axes Composition (BAC) of combining Multiple IMU (MIMU) sensors data for accurate 3D-pose estimation that takes into account both random and systematic errors by dynamically choosing the best IMU axes from the set of all available axes. We evaluate our approach on our MIMU visual-inertial sensor and compare the performance of the method with a purely probabilistic state-of-the-art approach of MIMU data fusion. We show that BAC outperforms the latter and achieves up to 20% accuracy improvement for both orientation and position estimation in open loop, but needs proper treatment to keep the obtained gain.Comment: Accepted to Robotics and Autonomous Systems journal. arXiv admin note: substantial text overlap with arXiv:2107.0263

A free-energy stable nodal discontinuous Galerkin approximation with summation-by-parts property for the Cahn-Hilliard equation

We present a nodal Discontinuous Galerkin (DG) scheme for the Cahn-Hilliard equation that satisfies the summation-by-parts simultaneous-approximation-term (SBP-SAT) property. The latter permits us to show that the discrete free-energy is bounded, and as a result, the scheme is provably stable. The scheme and the stability proof are presented for general curvilinear three-dimensional hexahedral meshes. We use the Bassi-Rebay 1 (BR1) scheme to compute interface fluxes, and an IMplicit-EXplicit (IMEX) scheme to integrate in time. Lastly, we test the theoretical findings numerically and present examples for two and three-dimensional problems

Open-Source LiDAR Time Synchronization System by Mimicking GPS-clock

Time synchronization of multiple sensors is one of the main issues when building sensor networks. Data fusion algorithms and their applications, such as LiDAR-IMU Odometry (LIO), rely on precise timestamping. We introduce open-source LiDAR to inertial measurement unit (IMU) hardware time synchronization system, which could be generalized to multiple sensors such as cameras, encoders, other LiDARs, etc. The system mimics a GPS-supplied clock interface by a microcontroller-powered platform and provides 1 microsecond synchronization precision. In addition, we conduct an evaluation of the system precision comparing to other synchronization methods, including timestamping provided by ROS software and LiDAR inner clock, showing clear advantages over both baseline methods.Comment: IEEE Sensors 2021 Conferenc

EVOLIN Benchmark: Evaluation of Line Detection and Association

Lines are interesting geometrical features commonly seen in indoor and urban environments. There is missing a complete benchmark where one can evaluate lines from a sequential stream of images in all its stages: Line detection, Line Association and Pose error. To do so, we present a complete and exhaustive benchmark for visual lines in a SLAM front-end, both for RGB and RGBD, by providing a plethora of complementary metrics. We have also labelled data from well-known SLAM datasets in order to have all in one poses and accurately annotated lines. In particular, we have evaluated 17 line detection algorithms, 5 line associations methods and the resultant pose error for aligning a pair of frames with several combinations of detector-association. We have packaged all methods and evaluations metrics and made them publicly available on web-page https://prime-slam.github.io/evolin/

Bayesian human motion intentionality prediction in urban environments

Human motion prediction in indoor and outdoor scenarios is a key issue towards human robot interaction and intelligent robot navigation in general. In the present work, we propose a new human motion intentionality indicator, denominated Bayesian Human Motion Intentionality Prediction (BHMIP), which is a geometric-based long-term predictor. Two variants of the Bayesian approach are proposed, the Sliding Window BHMIP and the Time Decay BHMIP. The main advantages of the proposed methods are: a simple formulation, easily scalable, portability to unknown environments with small learning effort, low computational complexity, and they outperform other state of the art approaches. The system only requires training to obtain the set of destinations, which are salient positions people normally walk to, that configure a scene. A comparison of the BHMIP is done with other well known methods for long-term prediction using the Edinburgh Informatics Forum pedestrian database and the Freiburg People Tracker database. (C) 2013 Elsevier B.V. All rights reserved.Peer ReviewedPostprint (published version