Accurate platoon control of urban vehicles, based solely on monocular vision (original) (raw)
Related papers
2008
To address traffic saturation in cities, new "Urban Transportation Systems", based on electric vehicles in freeaccess, are in developing. One necessary functionality of such systems is their ability to move in a platoon fashion. A global decentralized platoon control strategy, supported by inter-vehicle communications, is addressed in this paper, relying on nonlinear control techniques. The main interest in a global approach is that servoing error accumulation can be avoided, whatever the platoon length. However, absolute vehicle localization is then required. In urban applications, cameras are realistic sensors, but localization is supplied in a 3D visual virtual world, slightly distorted w.r.t. the actual metric one. To enable accurate guidance, local corrections to the visual world are here computed from the data supplied by a laser rangefinder mounted on the second vehicle, and then shared with the whole platoon. Full-scale experiments demonstrate the performance of the proposed approach.
Manual convoying of automated urban vehicles relying on monocular vision
2012 IEEE Intelligent Vehicles Symposium, 2012
This paper deals with platooning navigation in the context of innovative solutions for urban transportation systems. More precisely, the case of a manually driven vehicle leading a convoy of automated ones is considered. Vehicle localization relies solely on monocular vision: a 3D map of the environment is built beforehand from reference video sequences, and then used to derive vehicle absolute location from the current camera image. The 3D vision map presents however distortions w.r.t. a metric world, but these latter can be shown to be locally homogeneous. They can then be accurately corrected via a 1-dim. function evaluated with a nonlinear observer relying on odometric data. Next, the platoon reference trajectory is built as a B-Spline curve extended on-line via local optimization from the successive locations of the lead vehicle, and a global decentralized control strategy, supported by inter-vehicle communication, is designed to achieve accurate platooning with no oscillation within the convoy. Experimental results, carried out with two urban vehicles, demonstrate the capabilities of the proposed approach.
Decentralized 2-D control of vehicular platoons under limited visual feedback
2015 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), 2015
In this paper, we consider the two dimensional (2-D) predecessor-following control problem for a platoon of unicycle vehicles moving on a planar surface. More specifically, we design a decentralized kinematic control protocol, in the sense that each vehicle calculates its own control signal based solely on local information regarding its preceding vehicle, by its on-board camera, without incorporating any velocity measurements. Additionally, the transient and steady state response is a priori determined by certain designer-specified performance functions and is fully decoupled by the number of vehicles composing the platoon and the control gains selection. Moreover, collisions between successive vehicles as well as connectivity breaks, owing to the limited field of view of cameras, are provably avoided. Finally, an extensive simulation study is carried out in the WEBOTS TM realistic simulator, clarifying the proposed control scheme and verifying its effectiveness.
Nonlinear Control for Urban Vehicles Platooning, Relying upon a Unique Kinematic GPS
Index Terms— mobile robots, nonlinear control, platooning, Automatic Guided Vehicles, RTK GPS. Abstract— In order to solve problems of traffic saturation in cities, new alternative " Urban Transportation Systems " are based on electric vehicles in free-access. One necessary func-tionality of such systems is their ability to move in a platoon fashion. Platooning of these automatic guided vehicles, relying on RTK-GPS sensors and inter-vehicles communication, is addressed in this paper. More precisely, vehicles platoon is expected to follow a curved reference path. Relying on nonlinear control theory, lateral and longitudinal control are fully decoupled, and therefore addressed independently. To ensure passengers comfort, additional monitoring functions supervise our control system. Then, simulations followed by experiments carried out with urban vehicles, are presented.
A Global Control Strategy for Urban Vehicles Platooning relying on Nonlinear Decoupling Laws
— To solve problems of traffic saturation in cities, new alternative " Urban Transportation Systems " are based on electric vehicles in free-access. One necessary functionality of such systems is their ability to move in a platoon fashion. Platooning of these automatic guided vehicles, relying on RTK-GPS sensors and inter-vehicles communication, is addressed in this paper. The developed control law is based on a global control strategy; actually, it can take into account all the platoon state, and not only the immediate previous vehicle state. Distance here is understood as difference of curvilinear abscissa along a reference trajectory. Relying on nonlinear control theory, lateral and longitudinal control are fully decoupled, and therefore addressed independently. To ensure passengers comfort, additional monitoring functions supervise our control system. Then, experiment, carried out with urban vehicles, and simulations of long platoon, are presented.
Vision-based control for car platooning using homography decomposition
Proceedings - IEEE International Conference on Robotics and Automation, 2005
In this paper, we present a complete system for car platooning using visual tracking. The visual tracking is achieved by directly estimating the projective transformation (in our case a homography) between a selected reference template attached to the leading vehicle and the corresponding area in the current image. The relative position and orientation of the servoed car with regard to the leading one is computed by decomposing the homography. The control objective is stated in terms of path following task in order to cope with the non-holonomic constraints of the vehicles.
A unified nonlinear controller for a platoon of car-like vehicles
Proceedings of the 2004 American Control Conference, 2004
This paper presents a dynamics-based nonlinear tracking control scheme for a platoon of two car-like mobile robots. A unified controller is designed for both look-ahead and look-behind tracking. Look-ahead and look-behind tracking maneuvers require the following vehicle to follow the leading vehicle in two opposite directions: forward or backward, respectively. Furthermore, both steering control and driving control are also integrated in the unified controller. Tracking stability is ensured by proper design of a stable performance target equation. Simulation results show the control scheme work properly in both tracking cases. Simulations also investigate the influence of two important design parameters: the desired distance l and the desired steering angle ratio p. The results suggest that these parameters affect the system performance and require careful selection.
Robust control of large vehicular platoons with prescribed transient and steady state performance
53rd IEEE Conference on Decision and Control, 2014
In this paper, we consider the longitudinal control problem for a platoon of vehicles with unknown nonlinear dynamics. More specifically, we design a decentralized modelfree control protocol in the sense that each vehicle utilizes only local relative information regarding its front vehicle, obtained by its on-board sensors, to calculate its own control signal, without incorporating any prior knowledge of the model nonlinearities/disturbances or any approximation structures to acquire such knowledge. Additionally, the transient and steady state response is a priori determined by certain designerspecified performance functions and is fully decoupled by the agents' dynamic model, the number of vehicles composing the platoon and the control gains selection, which relaxes significantly the control design procedure. Moreover, introducing certain inter-vehicular distance constraints during the transient response shaping, collisions between successive vehicles as well as connectivity breaks owing to limited sensing capabilities are provably avoided. Finally, the proposed methodology results in a low complexity design. Actually, it is a static scheme involving very few and simple calculations to output the control signal, thus making its distributed implementation straightforward.
The Application of Reference-path Control to Vehicle Platoons
2008
A new algorithm for the control of vehicle platooning is proposed and tested on a robot-soccer test bed. We considered decentralized platooning, i.e., a virtual train of vehicles, where each vehicle is autonomous and decides on its motion based on its own perceptions. The platooning vehicles have non-holonomic constraints.
From autonomous navigation to platooning in urban context
— In this paper, the problem of autonomous navigation is addressed starting from the use of RTK-GPS until the use of vision as the main sensor. Using a decoupling strategy, it is possible to control separately lateral and longitudinal control in trajectory following tasks. Recent advances in vision, make possible to localize an urban vehicle in regard with a previously recorded trajectory. The concept of sensory memory (GPS, Vision), which tra-duces the learnt trajectory, is introduced and used to guide autonomously the vehicle. Then, an extension to vehicle platoon is described. Different kind of longitudinal control strategies are discussed : from a near to near approach, to a global strategy. Finally, in order to manage different kind of scenario which occur in a platoon context, a monitoring module is developed. All theses aspects are currently addressed through the BODEGA (ROBEA-CNRS national interdisciplinary research program) and MOBIVIP (PREDIT3 national research program) projects.