17 research outputs found
An Assessment on the Use of Stationary Vehicles as a Support to Cooperative Positioning
In this paper, we consider the use of stationary vehicles as tools to enhance
the localisation capabilities of moving vehicles in a VANET. We examine the
idea in terms of its potential benefits, technical requirements, algorithmic
design and experimental evaluation. Simulation results are given to illustrate
the efficacy of the technique.Comment: This version of the paper is an updated version of the initial
submission, where some initial comments of reviewers have been taken into
accoun
A Kalman-Yakubovich-Popov-type lemma for systems with certain state-dependent constraints
In this note, a result is presented that may be considered an extension of the classical Kalman-Yakubovich-Popov (KYP)
lemma. Motivated by problems in the design of switched systems, we wish to infer the existence of a quadratic Lyapunov
function (QLF) for a nonlinear system in the case where a matrix defining one system is a rank-1 perturbation of the other
and where switching between the systems is orchestrated according to a conic partitioning of the state space IRn. We show
that a necessary and sufficient condition for the existence of a QLF reduces to checking a single constraint on a sum of transfer
functions irrespective of problem dimension. Furthermore, we demonstrate that our conditions reduce to the classical KYP
lemma when the conic partition of the state space is IRn, with the transfer function condition reducing to the condition of
Strict Positive Realness
Herd Routes: A Preventative IoT-Based System for Improving Female Pedestrian Safety on City Streets
Over two thirds of women of all ages in the UK have experienced some form of
sexual harassment in a public space. Recent tragic incidents involving female
pedestrians have highlighted some of the personal safety issues that women
still face in cities today. There exist many popular location-based safety
applications as a result of this; however, these applications tend to take a
reactive approach where action is taken only after an incident has occurred.
This paper proposes a preventative approach to the problem by creating safer
public environments through societal incentivisation. The proposed system,
called "Herd Routes", improves the safety of female pedestrians by generating
busier pedestrian routes as a result of route incentivisation. A novel
application of distributed ledgers is proposed to provide security and trust, a
record of system users' locations and IDs, and a platform for token exchange. A
proof-of-concept was developed using the simulation package SUMO (Simulation of
Urban Mobility), and a smartphone app. was built in Android Studio so that
pedestrian Hardware-in-the-Loop testing could be carried out to validate the
technical feasibility and desirability of the system. With positive results
from the initial testing of the proof-of-concept, further development could
significantly contribute towards creating safer pedestrian routes through
cities, and tackle the societal change that is required to improve female
pedestrian safety in the long term
Quadratic Lyapunov Functions for Systems with State-Dependent Switching
In this paper, we consider the existence of quadratic Lyapunov functions for certain
types of switched linear systems. Given a partition of the state-space, a set of matrices
(linear dynamics), and a matrix-valued function A(x) constructed by associating these
matrices with regions of the state-space in a manner governed by the partition, we ask
whether there exists a positive definite symmetric matrix P such that A(x)T P +PA(x)
is negative definite for all x(t). For planar systems, necessary and sufficient conditions
are given. Extensions for higher order systems are also presented
A Large-Scale SUMO-Based Emulation Platform
A hardware-in-the-loop simulation platform for emulating large-scale intelligent transportation systems is presented. The platform embeds a real vehicle into SUMO, a microscopic road traffic simulation package. Emulations, consisting of the real vehicle, and potentially thousands of simulated vehicles, are run in real time. The platform provides an opportunity for real drivers to gain a feel of being in a large-scale, connected vehicle scenario. Various applications of the platform are presented
A Kalman-Yakubovich-Popov-type lemma for systems with certain state-dependent constraints
In this note, a result is presented that may be considered an extension of the classical Kalman-Yakubovich-Popov (KYP)
lemma. Motivated by problems in the design of switched systems, we wish to infer the existence of a quadratic Lyapunov
function (QLF) for a nonlinear system in the case where a matrix defining one system is a rank-1 perturbation of the other
and where switching between the systems is orchestrated according to a conic partitioning of the state space IRn. We show
that a necessary and sufficient condition for the existence of a QLF reduces to checking a single constraint on a sum of transfer
functions irrespective of problem dimension. Furthermore, we demonstrate that our conditions reduce to the classical KYP
lemma when the conic partition of the state space is IRn, with the transfer function condition reducing to the condition of
Strict Positive Realness
A Kalman-Yakubovich-Popov-type lemma for systems with certain state-dependent constraints
In this note, a result is presented that may be considered an extension of the classical Kalman-Yakubovich-Popov (KYP)
lemma. Motivated by problems in the design of switched systems, we wish to infer the existence of a quadratic Lyapunov
function (QLF) for a nonlinear system in the case where a matrix defining one system is a rank-1 perturbation of the other
and where switching between the systems is orchestrated according to a conic partitioning of the state space IRn. We show
that a necessary and sufficient condition for the existence of a QLF reduces to checking a single constraint on a sum of transfer
functions irrespective of problem dimension. Furthermore, we demonstrate that our conditions reduce to the classical KYP
lemma when the conic partition of the state space is IRn, with the transfer function condition reducing to the condition of
Strict Positive Realness