31 research outputs found
Designing Automated Vehicle and Traffic Systems towards Meaningful Human Control
Ensuring operational control over automated vehicles is not trivial and
failing to do so severely endangers the lives of road users. An integrated
approach is necessary to ensure that all agents play their part including
drivers, occupants, vehicle designers and governments. While progress is being
made, a comprehensive approach to the problem is being ignored, which can be
solved in the main through considering Meaningful Human Control (MHC). In this
research, an Integrated System Proximity framework and Operational Process
Design approach to assist the development of Connected Automated Vehicles (CAV)
under the consideration of MHC are introduced. These offer a greater
understanding and basis for vehicle and traffic system design by vehicle
designers and governments as two important influencing stakeholders. The
framework includes an extension to a system approach, which also considers ways
that MHC can be improved through updating: either implicit proximal updating or
explicit distal updating. The process and importance are demonstrated in three
recent cases from practice. Finally, a call for action is made to government
and regulatory authorities, as well as the automotive industry, to ensure that
MHC processes are explicitly included in policy, regulations, and design
processes to ensure future ad-vancement of CAVs in a responsible, safe and
humanly agreeable fashion.Comment: In: Research Handbook on Meaningful Human Control of Artificial
Intelligence Systems. Edward Elgar Publishin
Vehicle Specific Behaviour in Macroscopic Traffic Modelling through Stochastic Advection Invariant
AbstractIn this contribution a new model to include stochastic vehicle specific behaviour and interaction in traffic flow modelling is presented. The First Order Model with Stochastic Advection (FOMSA) is presented as a first order macroscopic kinematic wave model in a platoon-based Lagrangian coordinate system. The use of Lagrangian coordinates allows characteristics of specific vehicles or vehicle-groups to propagate along with the traffic flow using a vehicle specific invariant. The invariant reflects how vehicle or platoon specific characteristics propagate with the vehicles and influence the local behaviour of a vehicle or platoon on a macroscopic level and in interaction with other surrounding vehicles. It represents a local vehicle specific adjustment to the critical density and makes use of two parameters: a stochastic boundary parameter and a transition parameter. These parameters indicate the extent of differences between vehicles or platoons. A case study is also presented in which a demonstration of the model is given and the face validity and sensitivity of the parameters are shown. Previously, similar approaches have made use of second order model descriptions. The formulation of this model as a first order model makes use of the advantages of first order models and also applies the improved accuracy of Lagrangian coordinates over the Eulerian coordinate system in time-stepping
Towards improved handling of uncertainty in cost-benefit analysis: addressing the ‘price-quality’ and ‘communication’ dilemmas
An important limitation of Cost-Benefit Analysis (CBA) is the inherent uncertainty in estimations of future welfare effects. In this paper, we argue that consideration of the ‘pricequality’ dilemma and the ‘communication’ dilemma is useful to explain and improve the handling of uncertainty in CBA. The ‘price-quality’ dilemma refers to the trade-off between the quality of welfare effect estimations and the costs of providing these estimations. Instruments to produce good quality effect estimates (including uncertainties) can be expensive both in monetary terms and time. We discuss the application of probabilistic traffic models as a promising example of how the ‘price-quality’ dilemma can be solved. The ‘communication’ dilemma refers to the observation that both a poor communication and a too prominent communication of uncertainties can cause problems for decision-makers. We argue that cognitive psychological theory provides useful perspectives to solve this dilemma, by providing a psychological framework which might help to explain why different types of people process CBA information differently. The results of this research may enhance first insights into the questions how the two dilemmas can be solved
Pattern retrieval of traffic congestion using graph-based associations of traffic domain-specific features
The fast-growing amount of traffic data brings many opportunities for
revealing more insightful information about traffic dynamics. However, it also
demands an effective database management system in which information retrieval
is arguably an important feature. The ability to locate similar patterns in big
datasets potentially paves the way for further valuable analyses in traffic
management. This paper proposes a content-based retrieval system for
spatiotemporal patterns of highway traffic congestion. There are two main
components in our framework, namely pattern representation and similarity
measurement. To effectively interpret retrieval outcomes, the paper proposes a
graph-based approach (relation-graph) for the former component, in which
fundamental traffic phenomena are encoded as nodes and their spatiotemporal
relationships as edges. In the latter component, the similarities between
congestion patterns are customizable with various aspects according to user
expectations. We evaluated the proposed framework by applying it to a dataset
of hundreds of patterns with various complexities (temporally and spatially).
The example queries indicate the effectiveness of the proposed method, i.e. the
obtained patterns present similar traffic phenomena as in the given examples.
In addition, the success of the proposed approach directly derives a new
opportunity for semantic retrieval, in which expected patterns are described by
adopting the relation-graph notion to associate fundamental traffic phenomena.Comment: 20 pages, 14 figure
Will automated vehicles negatively impact traffic flow?
With low-level vehicle automation already available, there is a necessity to estimate its effects on traffic flow, especially if these could be negative. A long gradual transition will occur from manual driving to automated driving, in which many yet unknown traffic flow dynamics will be present. These effects have the potential to increasingly aid or cripple current road networks. In this contribution, we investigate these effects using an empirically calibrated and validated simulation experiment, backed up with findings from literature. We found that low-level automated vehicles in mixed traffic will initially have a small negative effect on traffic flow and road capacities. The experiment further showed that any improvement in traffic flow will only be seen at penetration rates above 70%. Also, the capacity drop appeared to be slightly higher with the presence of low-level automated vehicles. The experiment further investigated the effect of bottleneck severity and truck shares on traffic flow. Improvements to current traffic models are recommended and should include a greater detail and understanding of driver-vehicle interaction, both in conventional and in mixed traffic flow. Further research into behavioural shifts in driving is also recommended due to limited data and knowledge of these dynamics.
Document type: Articl
Inner approximations of stochastic programs for data-driven stochastic barrier function design
This paper studies finite-horizon safety guarantees for discrete-time
piece-wise affine systems with stochastic noise of unknown distributions. Our
approach is based on a novel approach to synthesise a stochastic barrier
function from noise data. In particular, we first build a chance-constraint
tightening to obtain an inner approximation of a stochastic program. Then, we
apply this methodology for stochastic barrier function design, yielding a
robust linear program to which the scenario approach theory applies. In
contrast to existing approaches, our method is data efficient as it only
requires the number of data to be proportional to the logarithm in the negative
inverse of the confidence level and is computationally efficient due to its
reduction to linear programming. Furthermore, while state-of-the-art methods
assume known statistics on the noise distribution, our approach does not
require any information about it. We empirically evaluate the efficacy of our
method on various verification benchmarks. Experiments show a significant
improvement with respect to state-of-the-art, obtaining tighter certificates
with a confidence that is several orders of magnitude higher
Large Car-following Data Based on Lyft level-5 Open Dataset: Following Autonomous Vehicles vs. Human-driven Vehicles
Car-Following (CF), as a fundamental driving behaviour, has significant
influences on the safety and efficiency of traffic flow. Investigating how
human drivers react differently when following autonomous vs. human-driven
vehicles (HV) is thus critical for mixed traffic flow. Research in this field
can be expedited with trajectory datasets collected by Autonomous Vehicles
(AVs). However, trajectories collected by AVs are noisy and not readily
applicable for studying CF behaviour. This paper extracts and enhances two
categories of CF data, HV-following-AV (H-A) and HV-following-HV (H-H), from
the open Lyft level-5 dataset. First, CF pairs are selected based on specific
rules. Next, the quality of raw data is assessed by anomaly analysis. Then, the
raw CF data is corrected and enhanced via motion planning, Kalman filtering,
and wavelet denoising. As a result, 29k+ H-A and 42k+ H-H car-following
segments are obtained, with a total driving distance of 150k+ km. A diversity
assessment shows that the processed data cover complete CF regimes for
calibrating CF models. This open and ready-to-use dataset provides the
opportunity to investigate the CF behaviours of following AVs vs. HVs from
real-world data. It can further facilitate studies on exploring the impact of
AVs on mixed urban traffic.Comment: 6 pages, 9 figure
Symptoms of depersonalisation/derealisation disorder as measured by brain electrical activity: A systematic review
Depersonalisation/derealisation disorder (DPD) refers to frequent and persistent detachment from bodily self and disengagement from the outside world. As a dissociative disorder, DPD affects 1–2 % of the population, but takes 7–12 years on average to be accurately diagnosed. In this systematic review, we comprehensively describe research targeting the neural correlates of core DPD symptoms, covering publications between 1992 and 2020 that have used electrophysiological techniques. The aim was to investigate the diagnostic potential of these relatively inexpensive and convenient neuroimaging tools. We review the EEG power spectrum, components of the event-related potential (ERP), as well as vestibular and heartbeat evoked potentials as likely electrophysiological biomarkers to study DPD symptoms. We argue that acute anxiety- or trauma-related impairments in the integration of interoceptive and exteroceptive signals play a key role in the formation of DPD symptoms, and that future research needs analysis methods that can take this integration into account. We suggest tools for prospective studies of electrophysiological DPD biomarkers, which are urgently needed to fully develop their diagnostic potential
Anterior insular cortex and emotional awareness.
This paper reviews the foundation for a role of the human anterior insular cortex (AIC) in emotional awareness, defined as the conscious experience of emotions. We first introduce the neuroanatomical features of AIC and existing findings on emotional awareness. Using empathy, the awareness and understanding of other people's emotional states, as a test case, we then present evidence to demonstrate: 1) AIC and anterior cingulate cortex (ACC) are commonly coactivated as revealed by a meta-analysis; 2) AIC is functionally dissociable from ACC; 3) AIC integrates stimulus-driven and top-down information; and 4) AIC is necessary for emotional awareness. We propose a model in which AIC serves two major functions: integrating bottom-up interoceptive signals with top-down predictions to generate a current awareness state; and providing descending predictions to visceral systems that provide a point of reference for autonomic reflexes. We argue that AIC is critical and necessary for, emotional awareness. J. Comp. Neurol., 2013. © 2013 Wiley Periodicals, Inc