Abstract

Localization has been regarded as one of the most fundamental problems to enable a mobile robot with autonomous capabilities. Probabilistic techniques such as Kalman or Particle filtering have long been used to solve robotic localization and mapping problem. Despite their good performance in practical applications, they could suffer inconsistency problems. This paper presents an Interval Constraint Satisfaction Problem (ICSP) graph based methodology for consistent car-like robot localization in outdoor environments. The localization problem is cast into a two-stage framework: visual teach and repeat. During a teaching phase, the interval map is built when a robot navigates around the environment with GPS-support. The map is then used for real-time ego-localization as the robot repeats the path autonomously. By dynamically solving the ICSP graph via Interval Constraint Propagation (ICP) techniques, a consistent and improved localization result is obtained. Both numerical simulation results and real data set experiments are presented, showing the soundness of the proposed method in achieving consistent localization.

Highlights

  • Localization is a problem for mobile robots to localize themselves in the environment with sensory information from their embedded sensors

  • The real-time localization result is obtained by using only the current knowledge of the observations; this localization result can be further improved by considering a dynamic Interval Constraint Satisfaction Problem (ICSP) graph in a sliding window during each timestep, such that the localization improvement due to the new observation can be propagated to the past through the graph architecture and improve the past localization

  • To test the feasibility of the proposed ICSP graph based visual teach method, we set up a simple numerical experiment

Read more

Summary

Introduction

Localization is a problem for mobile robots to localize themselves in the environment with sensory information from their embedded sensors. While some others get rid of dealing with the uncertainty probability distributions, they assumed that noise is unknown but bounded by real intervals Those methods provide solutions presented by a set of bounded configurations in which the robot is guaranteed to be, and they are classified as deterministic methods. The main advantage of interval analysis based localization over Kalman filtering or Bayesian methods is that they provide guaranteed solutions without the need to linearize the robot motion or the sensoring models, unlike the probabilistic counterparts that require linearization to facilitate the propagation of uncertainties. Interval methods do not assume any noise probability distribution in the system; they just require a soft assumption about the support of the noise, i.e., it is bounded by real intervals They can provide guaranteed and consistent results.

Principle of Interval
Operations of Interval Arithmetic
Contractor
Interval Consistency
Framework of Visual Teach
Motion Estimation
Bounded-Error Landmark Parameterization
ICSP Based Estimation
Graph Architecture
Graph Operation
Dynamic Graph Optimization
Real-Time Localization
Post-Localization
Consistency Evaluation
Numerical Results
Real Data Set Experiment
Conclusions
Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call