Anne Spalanzani

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39ranked-venue papers
1as first author
8since 2021 · last 2026
0000-0003-4813-4940ORCID · corroborated

Domains — the database's venue-derived domains; a paper can count in several

Artificial intelligence and machine learning · 36 · 1 first-author · 7 since 2021Systems, architecture and hardware · 21 · 3 since 2021Graphics, computer vision, multimedia, augmented reality and games · 5 · 1 since 2021Applied, interdisciplinary, general and emerging computing · 4 · 1 since 2021Human-computer interaction and ubiquitous computing · 2Databases, data management, data science and information retrieval · 1
YearPublicationVenuePosition
2026 PlanFlow: Local trajectory planning for autonomous driving using Flow-guided occupancy grids
Gustavo Salazar-Gomez, Anne Spalanzani, Lukas Rummelhard, Christian Laugier
IV2
2025 CG-Net: Urban Trajectory Forecasting with Bipartite Graphs for Agents, Scene Context and Candidate Centerlines
abstract
Trajectory forecasting in urban environments is a critical task that needs to be addressed for the safety of autonomous vehicles, particularly in urban road intersection scenarios, where agents exhibit diverse behaviors mainly due to complex interactions between agents and the environment and the diversity of paths available to the agents. Current state-of-the-art methods do not perform well in urban road intersection scenarios. To address this issue, the proposed novel framework CandidateGraph-Net (CG-Net), improves trajectory prediction in urban road intersection scenarios by encoding the available candidate centerlines at the current location of the target agent. The proposed interaction encoder in CG-Net is inspired by human behavior. It is modeled utilizing a bipartite graph attention network to predict the trajectory of the target agent. It estimates the trajectory in the same way as humans anticipate the trajectory of other vehicles and pedestrians in dynamic environments. The agent embeddings in the interaction encoder at each time step pay attention to nearby agents and surrounding scene elements simultaneously. This enables the model to learn how to prioritize interactions between nearby agents and the environment map. Further, CG-Net’s performance is evaluated using the Argoverse 2 motion forecasting dataset. The results demonstrate its effectiveness in urban road intersection scenarios, with an overall improvement in key metrics such as minFDE and minADE compared to baseline methods. These improvements highlight CG-Net’s ability to perform better motion forecasting in urban road intersection scenarios.
Kaushik Bhowmik, Anne Spalanzani, Philippe Martinet
IROS2
2024 How To Evaluate the Navigation of Autonomous Vehicles Around Pedestrians?
abstract
The navigation of autonomous vehicles around pedestrians is a key challenge when driving in urban environments. It is essential to test the proposed navigation system using simulation before moving to real-life implementation and testing. Evaluating the performance of the system requires the design of a diverse set of tests which spans the targeted working scenarios and conditions. These tests can then undergo a process of evaluation using a set of adapted performance metrics. This work addresses the problem of performance evaluation for an autonomous vehicle in a shared space with pedestrians. The methodology for designing the test simulations is discussed. Moreover, a group of performance metrics is proposed to evaluate the different aspects of the navigation: the motion safety, the quality of the generated trajectory and the comfort of the pedestrians surrounding the vehicle. Furthermore, the success/fail criterion for each metric is discussed. The implementation of the proposed evaluation method is illustrated by evaluating the performance of a pre-designed proactive navigation system using a shared space crowd simulator under Robot Operating System (ROS).
Maria Kabtoul, Manon Prédhumeau, Anne Spalanzani, Julie Dugdale, Philippe Martinet
IEEE Trans. Intell. Transp. Syst.3
2023 Vehicle Motion Forecasting Using Prior Information and Semantic-Assisted Occupancy Grid Maps
abstract
Motion prediction is a challenging task for autonomous vehicles due to uncertainty in the sensor data, the non-deterministic nature of future, and complex behavior of agents. In this paper, we tackle this problem by representing the scene as dynamic occupancy grid maps (DOGMs), associating semantic labels to the occupied cells and incorporating map information. We propose a novel framework that combines deep-learning-based spatio-temporal and probabilistic approaches to predict vehicle behaviors. Contrary to the conventional OGM prediction methods, evaluation of our work is conducted against the ground truth annotations. We experiment and validate our results on real-world NuScenes dataset and show that our model shows superior ability to predict both static and dynamic vehicles compared to OGM predictions. Furthermore, we perform an ablation study and assess the role of semantic labels and map in the architecture.
Rabbia Asghar, Manuel Diaz-Zapata, Lukas Rummelhard, Anne Spalanzani, Christian Laugier
IROS4
2023 Interaction-aware Predictive Collision Detector for Human-aware Collision Avoidance
abstract
With their progressive deployment in increasingly complex environments, autonomous vehicles will more often interact with humans in shared spaces. However proactive planners, the most effective for human-aware navigation, are rarely applicable with real-world constraints because of their inherent complexity. Meanwhile classical approaches fail to navigate in cooperation with humans in complex or crowded scenarios. Therefore we propose to extend a global kinodynamic predictive collision avoidance approach with an interaction-aware behavioral prediction model for human-vehicle interactions. Thanks to a grid based Bayesian perception, our approach is versatile in modeling uncertainty and complex scenes. We deploy this solution on a robotic car and show that it can be used in real-world applications. With a qualitative and quantitative validation, we show that this interaction-aware collision avoidance solution is safe and performs well in crowded scenarios. Less computationally demanding and more versatile than proactive planners but still able to benefit from cooperation with humans, this interaction-aware approach offers a compromise between predictive and proactive planners.
Thomas Genevois, Anne Spalanzani, Christian Laugier
IV2
2022 Allo-centric Occupancy Grid Prediction for Urban Traffic Scene Using Video Prediction Networks
abstract
Prediction of dynamic environment is crucial to safe navigation of an autonomous vehicle. Urban traffic scenes are particularly challenging to forecast due to complex interactions between various dynamic agents, such as vehicles and vulnerable road users. Previous approaches have used ego-centric occupancy grid maps to represent and predict dynamic environments. However, these predictions suffer from blurriness, loss of scene structure at turns, and vanishing of agents over longer prediction horizon. In this work, we propose a novel framework to make long-term predictions by representing the traffic scene in a fixed frame, referred as allo-centric occupancy grid. This allows for the static scene to remain fixed and to represent motion of the ego-vehicle on the grid like other agents'. We study the allo-centric grid prediction with different video prediction networks and validate the approach on the real-world Nuscenes dataset. The results demonstrate that the allo-centric grid representation significantly improves scene prediction, in comparison to the conventional ego-centric grid approach.
Rabbia Asghar, Lukas Rummelhard, Anne Spalanzani, Christian Laugier
ICARCV3
2022 Proactive And Smooth Maneuvering For Navigation Around Pedestrians
abstract
Navigation in close proximity with pedestrians is a challenge on the way to fully automated vehicles. Pedestrian-friendly navigation requires an understanding of pedestrian reaction and intention. Merely safety based reactive systems can lead to sub-optimal navigation solutions resulting in the freezing of the vehicle in many scenarios. Moreover, a strictly reactive method can produce unnatural driving patterns which cannot guarantee the legibility or social acceptance of the automated vehicle. This work presents a proactive maneuvering method adapted to navigation in close interaction with pedestrians using a dynamic channel approach. The method allows to proactively explore the navigation options based on anticipating pedestrians cooperation. The navigation is tested in frontal and lateral crossing scenarios with variable space density. The system is implemented under ROS, and compared with the probabilistic Risk-RRT planning method. The results are evaluated based on the safety and comfort of the pedestrians, and the quality of the vehicle's trajectory.
Maria Kabtoul, Anne Spalanzani, Philippe Martinet
ICRA2
2022 Agent-Based Modeling for Predicting Pedestrian Trajectories Around an Autonomous Vehicle
abstract
This paper addresses modeling and simulating pedestrian trajectories when interacting with an autonomous vehicle in a shared space. Most pedestrian–vehicle interaction models are not suitable for predicting individual trajectories. Data-driven models yield accurate predictions but lack generalizability to new scenarios, usually do not run in real time and produce results that are poorly explainable. Current expert models do not deal with the diversity of possible pedestrian interactions with the vehicle in a shared space and lack microscopic validation. We propose an expert pedestrian model that combines the social force model and a new decision model for anticipating pedestrian–vehicle interactions. The proposed model integrates different observed pedestrian behaviors, as well as the behaviors of the social groups of pedestrians, in diverse interaction scenarios with a car. We calibrate the model by fitting the parameters values on a training set. We validate the model and evaluate its predictive potential through qualitative and quantitative comparisons with ground truth trajectories. The proposed model reproduces observed behaviors that have not been replicated by the social force model and outperforms the social force model at predicting pedestrian behavior around the vehicle on the used dataset. The model generates explainable and real-time trajectory predictions. Additional evaluation on a new dataset shows that the model generalizes well to new scenarios and can be applied to an autonomous vehicle embedded prediction.
Manon Prédhumeau, Lyuba Mancheva, Julie Dugdale, Anne Spalanzani
J. Artif. Intell. Res.4
2020 Behavioral decision-making for urban autonomous driving in the presence of pedestrians using Deep Recurrent Q-Network
abstract
Decision making for autonomous driving in urban environments is challenging due to the complexity of the road structure and the uncertainty in the behavior of diverse road users. Traditional methods consist of manually designed rules as the driving policy, which require expert domain knowledge, are difficult to generalize and might give sub-optimal results as the environment gets complex. Whereas, using reinforcement learning, optimal driving policy could be learned and improved automatically through several interactions with the environment. However, current research in the field of reinforcement learning for autonomous driving is mainly focused on highway setup with little to no emphasis on urban environments. In this work, a deep reinforcement learning based decision-making approach for high-level driving behavior is proposed for urban environments in the presence of pedestrians. For this, the use of Deep Recurrent Q-Network (DRQN) is explored, a method combining state-of-the art Deep Q-Network (DQN) with a long term short term memory (LSTM) layer helping the agent gain a memory of the environment. A 3-D state representation is designed as the input combined with a well defined reward function to train the agent for learning an appropriate behavior policy in a real-world like urban simulator. The proposed method is evaluated for dense urban scenarios and compared with a rule-based approach and results show that the proposed DRQN based driving behavior decision maker outperforms the rule-based approach.
Niranjan Deshpande, Dominique Vaufreydaz, Anne Spalanzani
ICARCV3
2020 Game theoretic decision making based on real sensor data for autonomous vehicles' maneuvers in high traffic
abstract
This paper presents an approach for implementing game theoretic decision making in combination with realistic sensory data input so as to allow an autonomous vehicle to perform maneuvers, such as lane change or merge in high traffic scenarios. The main novelty of this work, is the use of realistic sensory data input to obtain the observations as input of an iterative multi-player game in a realistic simulator. The game model allows to anticipate reactions of additional vehicles to the movements of the ego-vehicle without using any specific coordination or vehicle-to-vehicle communication. Moreover, direct information from the simulator, such as position or speed of the vehicles is also avoided.The solution of the game is based on cognitive hierarchy reasoning and it uses Monte Carlo reinforcement learning in order to obtain a near-optimal policy towards a specific goal. Moreover, the game proposed is capable of solving different situations using a single policy. The system has been successfully tested and compared with previous techniques using a realistic hybrid simulator, where the ego-vehicle and its sensors are simulated on a 3D simulator and the additional vehicles' behavior is obtained from a traffic simulator.
Mario Andrei Garzon Oviedo, Anne Spalanzani
ICRA2
2020 Towards Proactive Navigation: A Pedestrian-Vehicle Cooperation Based Behavioral Model
abstract
Developing autonomous vehicles capable of navigating safely and socially around pedestrians is a major challenge in intelligent transportation. This challenge cannot be met without understanding pedestrians' behavioral response to an autonomous vehicle, and the task of building a clear and quantitative description of the pedestrian to vehicle interaction remains a key milestone in autonomous navigation research. As a step towards safe proactive navigation in a space shared with pedestrians, this work introduces a pedestrian-vehicle interaction behavioral model. The model estimates the pedestrian's cooperation with the vehicle in an interaction scenario by a quantitative time-varying function. Using this cooperation estimation the pedestrian's trajectory is predicted by a cooperation-based trajectory planning model. Both parts of the model are tested and validated using real-life recorded scenarios of pedestrian-vehicle interaction. The model is capable of describing and predicting agents' behaviors when interacting with a vehicle in both lateral and frontal crossing scenarios.
Maria Kabtoul, Anne Spalanzani, Philippe Martinet
ICRA2
2020 Employing Severity of Injury to Contextualize Complex Risk Mitigation Scenarios
abstract
Risk mitigation is an important element to consider in risk evaluation. Safety features have helped to decrease the death ratio over the years. However, to date, each driver assistance system works on a single domain of operation. The problem remains in how to use perception to contextualize the scene to fully minimize the collision severity in a complex emergency scenario. Up to now, works on cost maps have consider simple contextualized object in mitigation scenarios. For instance, the use of binary allowed/forbidden zones or, a fixed weight to each type of object in the scene. Our work employs the risk of injury issued by accidentology to each class of object present in the scene. Each class of object presents an injury probability with respect to the impact speed and ethical/economical/political factors. The method generates a cost map containing a collision probability along with to the risk of injury. It dynamically contextualizes the objects, since the risk of injury depends on the characteristics of the scene. Simulation and dataset results validate that changing the referred parameters alters the context and evaluation of the scene. Then, the proposed method allows a better assessment of the surroundings by creating a dynamic navigation cost map for complex scenarios.
Luiz Alberto Serafim Guardini, Anne Spalanzani, Christian Laugier, Philippe Martinet, Anh-Lam Do, Thierry Hermitte
IV2
2019 Socially Compliant Navigation in dense crowds
abstract
Navigating in complex and highly dynamic environments such as crowds is still a major challenge for autonomous vehicle such as autonomous wheelchairs or even autonomous cars. This article presents a new way of navigating in crowds by using behavioral clustering for the surrounding agents and representing the crowd as a set of moving polygons. Once the environment has been modelled in this way and the robot has all the information it needs, we then propose a navigation algorithm that is able to guide the vehicle through the scene. The key-points of this algorithm are that (1) it can avoid densely-populated areas in order to minimize the risk of being on a collision course with any of the surrounding dynamic obstacles, (2) it generates socially compliant trajectories.
Roman Bresson, Jacques Saraydaryan, Julie Dugdale, Anne Spalanzani
IV4
2018 An hybrid simulation tool for autonomous cars in very high traffic scenarios
abstract
This article introduces an open source tool for simulating autonomous vehicles in complex, high traffic, scenarios. The proposed approach consists on creating an hybrid simulation, which fully integrates and synchronizes two well known simulators: a microscopic, multi-modal traffic simulator and a complex 3D simulator. The presented software tool allows to simulate an autonomous vehicle, including all its dynamics, sensors and control layers, in a scenario with a very high volume of traffic. The hybrid simulation creates a bi-directional integration, meaning that, in the 3D simulator, the ego-vehicle sees and interacts with the rest of the vehicles, and at the same time, in the traffic simulator, all additional vehicles detect and react to the actions of the ego-vehicle. Two interfaces, one for each simulator, where created to achieve the integration, they ensure the synchronization of the scenario, the state of all vehicles including the ego-vehicle, and the time. The capabilities of the hybrid simulation was tested with different models for the ego-vehicle and almost 300 additional vehicles in a complex merge scenario.
Mario Andrei Garzon Oviedo, Anne Spalanzani
ICARCV2
2018 Building Prior Knowledge: A Markov Based Pedestrian Prediction Model Using Urban Environmental Data
abstract
Autonomous Vehicles navigating in urban areas have a need to understand and predict future pedestrian behavior for safer navigation. This high level of situational awareness requires observing pedestrian behavior and extrapolating their positions to know future positions. While some work has been done in this field using Hidden Markov Models (HMMs), one of the few observed drawbacks of the method is the need for informed priors for learning behavior. In this work, an extension to the Growing Hidden Markov Model (GHMM) method is proposed to solve some of these drawbacks. This is achieved by building on existing work using potential cost maps and the principle of Natural Vision. As a consequence, the proposed model is able to predict pedestrian positions more precisely over a longer horizon compared to the state of the art. The method is tested over “legal” and “illegal” behavior of pedestrians, having trained the model with sparse observations and partial trajectories. The method, with no training data, is compared against a trained state of the art model. It is observed that the proposed method is robust even in new, previously unseen areas.
Pavan Vasishta, Dominique Vaufreydaz, Anne Spalanzani
ICARCV3
2018 Personal Space of Autonomous Car's Passengers Sitting in the Driver's Seat
abstract
This article deals with the specific context of an autonomous car navigating in an urban center within a shared space between pedestrians and cars. The driver delegates the control to the autonomous system while remaining seated in the driver's seat. The proposed study aims at giving a first insight into the definition of human perception of space applied to vehicles by testing the existence of a personal space around the car. It aims at measuring proxemic information about the driver's comfort zone in such conditions. Proxemics, or human perception of space, has been largely explored when applied to humans or to robots, leading to the concept of personal space, but poorly when applied to vehicles. In this article, we highlight the existence and the characteristics of a zone of comfort around the car which is not correlated to the risk of a collision between the car and other road users. Our experiment includes 19 volunteers using a virtual reality headset to look at 30 scenarios filmed in 360° from the point of view of a passenger sitting in the driver's seat of an autonomous car. They were asked to say “stop” when they felt discomfort visualizing the scenarios. As said, the scenarios voluntarily avoid collision effect as we do not want to measure fear but discomfort. The scenarios involve one or three pedestrians walking past the car at different distances from the wings of the car, relative to the direction of motion of the car, on both sides. The car is either static or moving straight forward at different speeds. The results indicate the existence of a comfort zone around the car in which intrusion causes discomfort. The size of the comfort zone is sensitive neither to the side of the car where the pedestrian passes nor to the number of pedestrians. In contrast, the feeling of discomfort is relative to the car's motion (static or moving). Another outcome from this study is an illustration of the usage of first person 360° video and a virtual reality headset to evaluate feelings of a passenger within an autonomous car.
Eleonore Ferrier-Barbut, Dominique Vaufreydaz, Jean-Alix David, Jérôme Lussereau, Anne Spalanzani
Intelligent Vehicles Symposium5
2016 A semi-autonomous framework for human-aware and user intention driven wheelchair mobility assistance
abstract
An important aspect to be taken care of while designing assistive robots for mobility is that they need to operate among humans. Thus understanding human spatial social conventions and incorporating them in the assistive solutions, is important. In this paper, we introduce a semi-autonomous framework for assistive wheelchair navigation in human environments, which is driven by the intention of the wheelchair user. Safe and socially compliant motion provided by a user intention driven local motion planner is fused with user teleoperation in order to create such a system. Taking into account the fact that the user is the primary controller, our proposed system aims to provide progressive assistance whenever the user is in danger of collision or at risk of disturbance to other humans. We also thus propose generalized formulations for estimating user intentions and for sharing control within the context of wheelchair mobility assistance, that is adaptable in order to be deployed in real world systems. We then evaluate the proposed framework in simulation in order to obtain a quantitative analysis. We also provide experimental evidence using an off-the-shelf robotized wheelchair equipped with a single 2D laser scanner.
Vishnu K. Narayanan, Anne Spalanzani, Marie Babel
IROS2
2016 Analysis of an adaptive strategy for equitably approaching and joining human interactions
abstract
Since social, assistive and companion robots need to navigate within human crowds, understanding spatial social conventions while designing navigation solutions for such robots is an essential issue. This work presents analysis of an socially compliant robot motion strategy that could be employed by social robots such as humanoids, service robots or intelligent wheelchairs, for approaching and joining humans groups in interaction, and then become an equitable part of the interaction. Following our previous work that formalized the motion strategy, a detailed synthesis is presented here with experiments that validate the proposed system in the real world.
Vishnu K. Narayanan, Anne Spalanzani, Ren C. Luo, Marie Babel
RO-MAN2
2015 On equitably approaching and joining a group of interacting humans
abstract
In this work we introduce a low-level system that could be employed by a social robot like a robotic wheelchair or a humanoid, for approaching a group of interacting humans, in order to become a part of the interaction. Taking into account an interaction space that is created when at least two humans interact, a meeting point can be calculated where the robot should reach in order to equitably share space among the interacting group. We propose a sensor-based control task which uses the position and orientation of the humans with respect to the sensor as inputs, to reach the said meeting point while respecting spatial social constraints. Trials in simulation demonstrate the convergence of the control task and its capability as a low-level system for human-aware navigation.
Vishnu K. Narayanan, Anne Spalanzani, François Pasteau, Marie Babel
IROS2
2014 Using social cues to estimate possible destinations when driving a robotic wheelchair
abstract
Approaching a group of humans is an important navigation task. Although many methods have been proposed to avoid interrupting groups of people engaged in a conversation, just a few works have considered the proper way of joining those groups. Research in the field of social sciences have proposed geometric models to compute the best points to join a group. In this article we propose a method to use those points as possible destinations when driving a robotic wheelchair. Those points are considered together with other possible destinations in the environment such as points of interest or typical static destinations defined by the user's habits. The intended destination is inferred using a Dynamic Bayesian Network that takes into account the contextual information of the environment and user's orders to compute the probability for each destination.
Jesús-Arturo Escobedo-Cabello, Anne Spalanzani, Christian Laugier
IROS2
2014 Adaptive spacing in human-robot interactions
abstract
Social spacing in human-robot interactions is among the main useful features when integrating human social intelligence into robot perception and action skills. One of the main challenges, is to capture the transitions incurred by the human and further take into account robot constraints. Towards this goal, we introduce a novel methodology that can instantiate diverse social spacing models depending on the context and further as a function of uncertainty and robot perception capacity. Our method is based on the use of non-stationary, skew-normal probability density functions for the space of individuals and on treating multi-person space interactions through social mapping. The utility of our approach is shown on an indoor robot operating in the presence of humans, allowing it to exhibit socially intelligent responses.
Panagiotis Papadakis, Patrick Rives, Anne Spalanzani
IROS3
2014 On leader following and classification
abstract
Service and assistance robots that must move in human environment must address the difficult issue of navigating in dynamic environments. As it has been shown in previous works, in such situations the robots can take advantage of the motion of persons by following them, managing to move together with humans in difficult situations. In those circumstances, the problem to be solved is how to choose a human leader to be followed. This work proposes an innovative method for leader selection, based on human experience. A learning framework is developed, where data is acquired, labeled and then used to train an AdaBoost classification algorithm, to determine if a candidate is a bad or a good leader, and also to study the contribution of features to the classification process.
Procopio Stein, Anne Spalanzani, Vítor M. F. Santos, Christian Laugier
IROS2
2013 Multimodal control of a robotic wheelchair: Using contextual information for usability improvement
abstract
In this paper, a method to perform semi-autonomous navigation on a wheelchair is presented. The wheelchair could be controlled in semi-autonomous mode estimating the user's intention by using a face pose recognition system or in manual mode. The estimator was performed within a Bayesian network approach. To switch these two modes, a speech interface was used. The user's intention was modeled as a set of typical destinations visited by the user. The algorithm was implemented to one experimental wheelchair robot. The new application of the wheelchair system with more natural and easy-to-use human machine interfaces was one of the main contributions. as user's habits and points of interest are employed to infer the user's desired destination in a map. Erroneous steering signals coming from the user-machine interface input are filtered out, improving the overall performance of the system. Human aware navigation, path planning and obstacle avoidance are performed by the robotic wheelchair while the user is just concerned with “looking where he wants to go”.
Jesús-Arturo Escobedo-Cabello, Anne Spalanzani, Christian Laugier
IROS2
2013 Social mapping of human-populated environments by implicit function learning
abstract
With robots technology shifting towards entering human populated environments, the need for augmented perceptual and planning robotic skills emerges that complement to human presence. In this integration, perception and adaptation to the implicit human social conventions plays a fundamental role. Toward this goal, we propose a novel framework that can model context-dependent human spatial interactions, encoded in the form of a social map. The core idea of our approach resides in modelling human personal spaces as non-linearly scaled probability functions within the robotic state space and devise the structure and shape of a social map by solving a learning problem in kernel space. The social borders are subsequently obtained as isocontours of the learned implicit function that can realistically model arbitrarily complex social interactions of varying shape and size. We present our experiments using a rich dataset of human interactions, demonstrating the feasibility and utility of the proposed approach and promoting its application to social mapping of human-populated environments.
Panagiotis Papadakis, Anne Spalanzani, Christian Laugier
IROS2
2013 Navigating in populated environments by following a leader
abstract
Service robots have a great potential of improving human quality of life by aiding in everyday tasks. However, robots that share an environment and interact with humans still face some challenges that limits their acceptance. One of these challenges is how to move and behave among groups of people, which is a task performed seamlessly by humans and some animals. Motion planning in dynamic environments has been addressed mostly by predicting future position of humans and avoiding them. However, with the increase of the number of persons in such environments, techniques that are based only on the prediction of the movement of humans can fail, as they usually ignore the human's reaction to the presence of the robot. Instead of trying to model the complex human motion behavior, this work proposes to rely on humans to guide the robot through difficult situations, where modern approaches would fail to find a solution. This will be accomplished by a probabilistic approach for selecting a human leader, according to the robot's desired destination. In this way, the robot can take advantage of the humans' paths and behavior, effortlessly avoiding dynamic and static features together with the human leader, relieving the robot from the burden of having to generate its own path in difficult situations.
Procopio Stein, Vítor M. F. Santos, Anne Spalanzani, Christian Laugier
RO-MAN3
2012 Leader selection and following in dynamic environments
abstract
A crucial requirement for service robots is to be able to move in dynamic environments shared with humans as well as interact with them. Navigation in such environments is a challenging task, as the environment is constantly changing, future states have to be predicted and planning and execution must be carried on-line. However, even in very complex situations, humans can easily find a path that avoid both dynamic agents and static obstacles. This paper proposes a technique to take advantage of the human movement in such populated environments, using a probabilistic approach for the leader selection, according to the robot's desired destination. By choosing a leader to be followed in dynamic environments, the robot can take advantage of the paths traveled by humans or other robots, effortlessly avoiding dynamic and static features as its leader does, relieving the robot from the burden of having to generate its own path. Both the leader selection and the leader following algorithms have been tested in a real environment, with a robotic wheelchair.
Procopio Stein, Anne Spalanzani, Christian Laugier, Vítor M. F. Santos
ICARCV2
2012 Navigating between people: A stochastic optimization approach
abstract
The objective of this paper is to present a strategy to safely move a robot in an unknown and complex environment where people are moving and interacting. The robot, by using only its sensor data, must navigate respecting humans' comfort. To obtain good results in such a dynamic environment, a prediction on humans' movement is also crucial. To solve all the aforementioned problems we introduce a suitable cost function. Its optimization is obtained by using a new stochastic and adaptive optimization algorithm (CAO). This method is very useful in particular when the analytical expression of the optimization function is unknown but numerical values are available for any state configuration. Additionally, the proposed method can easily incorporate any dynamical and environmental constraints. To validate the performance of the proposed solution, several simulation results are provided.
Jorge Ríos-Martínez, Alessandro Renzaglia, Anne Spalanzani, Agostino Martinelli, Christian Laugier
ICRA3
2012 A Visibility-Based Approach for Occupancy Grid Computation in Disparity Space
abstract
Occupancy grids are a very convenient tool for environment representation in robotics. This paper will detail a novel approach for computing occupancy grids from stereo vision and show its application to intelligent vehicles. In the proposed approach, occupancy is initially computed directly in the stereoscopic sensor's disparity space. The calculation formally accounts for the detection of obstacles and road pixels in disparity space, as well as partial occlusions in the scene. In the second stage, this disparity-space occupancy grid is transformed into a Cartesian space occupancy grid to be used by subsequent applications. This transformation includes spatial and temporal filtering. The proposed method is designed to easily be processed in parallel. Consequently, we chose to implement it on a graphics processing unit, which allows real-time processing for demanding applications. In this paper, we present this method, and we propose an application to the problem of perception in a road environment. Results are presented with real road data, qualitatively comparing this approach with other methods.
Mathias Perrollaz, John-David Yoder, Amaury Nègre, Anne Spalanzani, Christian Laugier
IEEE Trans. Intell. Transp. Syst.4
2011 Understanding human interaction for probabilistic autonomous navigation using Risk-RRT approach
abstract
With the growing demand of personal assistance to mobility and mobile service robotics, robot navigation systems must be ¿aware¿ of the social conventions followed by people. They must respect proximity constraints but also respect people interacting. For example, they may not break interaction between people talking, unless the occupants want to take part in the conversation. In this case, they must be able to join the group using a socially adapted behavior. This paper proposes a risk-based navigation method including both the traditional notion of risk of collision and the notion of risk of disturbance. Results exhibit new emerging behavior showing how a robot takes into account social conventions in its navigation strategy.
Jorge Ríos-Martínez, Anne Spalanzani, Christian Laugier
IROS2
2010 Using the disparity space to compute occupancy grids from stereo-vision
abstract
The occupancy grid is a popular tool for probabilistic robotics, used for a variety of applications. Such grids are typically based on data from range sensors (e.g. laser, ultrasound), and the computation process is well known. The use of stereo-vision in this framework is less common, and typically treats the stereo sensor as a distance sensor, or fails to account for the uncertainties specific to vision. In this paper, we propose a novel approach to compute occupancy grids from stereo-vision, for the purpose of intelligent vehicles. Occupancy is initially computed directly in the stereoscopic sensor's disparity space, using the sensor's pixel-wise precision during the computation process and allowing the handling of occlusions in the observed area. It is also computationally efficient, since it uses the u-disparity approach to avoid processing a large point cloud. In a second stage, this disparity-space occupancy is transformed into a Cartesian space occupancy grid to be used by subsequent applications. In this paper, we present the method and show results obtained with real road data, comparing this approach with others.
Mathias Perrollaz, John-David Yoder, Anne Spalanzani, Christian Laugier
IROS3
2010 Probabilistic representation of the uncertainty of stereo-vision and application to obstacle detection
abstract
Stereo-vision is extensively used for intelligent vehicles, mainly for obstacle detection, as it provides a large amount of data. Many authors use it as a classical 3D sensor which provides a large tri-dimensional cloud of metric measurements, and apply methods usually designed for other sensors, such as clustering based on a distance. For stereo-vision, the measurement uncertainty is related to the range. For medium to long range, often necessary in the field of intelligent vehicles, this uncertainty has a significant impact, limiting the use of this kind of approaches. On the other hand, some authors consider stereo-vision more like a vision sensor and choose to directly work in the disparity space. This provides the ability to exploit the connectivity of the measurements, but roughly takes into consideration the actual size of the objects. In this paper, we propose a probabilistic representation of the specific uncertainty for stereo-vision, which takes advantage of both aspects - distance and disparity. The model is presented and then applied to obstacle detection, using the occupancy grid framework. For this purpose, a computationally-efficient implementation based on the u-disparity approach is given.
Mathias Perrollaz, Anne Spalanzani, Didier Aubert
Intelligent Vehicles Symposium2
2009 Probabilistic motion planning among moving obstacles following typical motion patterns
abstract
The paper presents a navigation algorithm for dynamic probabilistic environments. The static environment is unknown; moving pedestrians are detected and tracked on-line. Pedestrians are supposed to move along typical motion patterns represented by HMMs. The planning algorithm is based on an extension of the rapidly-exploring random tree algorithm, where the likelihood of the obstacles future trajectory and the probability of collision is explicitly taken into account. The algorithm is used in a partial motion planner, and the probability of collision is updated in real-time according to the most recent estimation. Results show the performance for a car-like robot in a simulated environment among multiple dynamic obstacles.
Chiara Fulgenzi, Anne Spalanzani, Christian Laugier
IROS2
2008 Probabilistic navigation in dynamic environment using Rapidly-exploring Random Trees and Gaussian processes
abstract
The paper describes a navigation algorithm for dynamic, uncertain environment. Moving obstacles are supposed to move on typical patterns which are pre-learned and are represented by Gaussian processes. The planning algorithm is based on an extension of the rapidly-exploring random tree algorithm, where the likelihood of the obstacles trajectory and the probability of collision is explicitly taken into account. The algorithm is used in a partial motion planner, and the probability of collision is updated in real-time according to the most recent estimation. Results show the performance of the navigation algorithm for a car-like robot moving among dynamic obstacles with probabilistic trajectory prediction.
Chiara Fulgenzi, Christopher Tay, Anne Spalanzani, Christian Laugier
IROS3
2007 Dynamic Obstacle Avoidance in uncertain environment combining PVOs and Occupancy Grid
abstract
Abstract — Most of present work for autonomous navigation in dynamic environment doesn’t take into account the dynamics of the obstacles or the limits of the perception system. To face these problems we applied the Probabilistic Velocity Obstacle (PV O) approach [1] to a dynamic occupancy grid. The paper presents a method to estimate the probability of collision where uncertainty in position, shape and velocity of the obstacles, occlusions and limited sensor range contribute directly to the computation. A simple navigation algorithm is then presented in order to apply the method to collision avoidance and goal driven control. Simulation results show that the robot is able to adapt its behaviour to the level of available knowledge and navigate safely among obstacles with a constant linear velocity. Extensions to non-linear, non-constant velocities are proposed. I.
Chiara Fulgenzi, Anne Spalanzani, Christian Laugier
ICRA2
2006 Pedestrians Tracking Using Offboard Cameras
abstract
In this paper, we detail the hardware and software perception system designed and developed to track pedestrians using a set of offboard cameras. It has been used in the context of vulnerable safety in a car park. This architecture is divided in two parts: a fusion part to fusion the data given by the set of offboard cameras and a tracking part to sequentially estimate the position of each pedestrian present in the environment and to determine the number of pedestrians. Finally, some experimental results are presented
Olivier Aycard, Anne Spalanzani, Julien Burlet, Chiara Fulgenzi, Trung-Dung Vu, David Raulo, Manuel Yguel
IROS2
2006 Adaptive Interacting Multiple Models applied on pedestrian tracking in car parks
abstract
To address perception problems we must be able to track dynamics targets of the environment. An important issue of tracking is filtering problem in which estimates of the target's state are computed while observations are progressively received. This paper presents an adaptive interacting multiple models (IMM) based filtering method. Interacting multiple models have been successfully applied to many applications as they allow, using several filters in parallel, to deal with the uncertainty on motion model, a critical component of filtering. Indeed targets can rapidly change their motion over a lapse of time. This is the case of pedestrians for which it is difficult to define an unique motion model which matches all their possible displacements. Nevertheless, the transition probability matrix (TPM) which models the interaction between different filters in an IMM is in currently defined a priori or needs an important amount of tuning to be used efficiently. In this paper, we put forward a method which automatically adapts online the TPM. The TPM adaptation using on-line data significantly improves the effectiveness of IMM filtering and so better target estimates are obtained. To validate our work we applied our method to pedestrian tracking in car parks on a real platform
Julien Burlet, Olivier Aycard, Anne Spalanzani, Christian Laugier
IROS3
2005 Auto-supervised learning in the Bayesian Programming Framework
abstract
Domestic and real world robotics requires continuous learning of new skills and behaviors to interact with humans. Auto-supervised learning, a compromise between supervised and completely unsupervised learning, consist in relying on previous knowledge to acquire new skills. We propose here to realize auto-supervised learning by exploiting statistical regularities in the sensorimotor space of a robot. In our context, it corresponds to achieve feature selection in a Bayesian programming framework. We compare several feature selection algorithms and validate them on a real robotic experiment.
Pierre Dangauthier, Pierre Bessière, Anne Spalanzani
ICRA3
2000 EVERA: An Evolutionary Programming Environment for Adaptive Speech Processing
Harouna Kabré, Anne Spalanzani
Inf. Sci.2
1998 Evolution, Learning and Speech Recognition in Changing Acoustic Environments
Anne Spalanzani, Harouna Kabré
PPSN1