Adaptive Driving Agent
From Driving a Machine to Riding with a Friend
Claudia V. Goldman† Albert Harounian Ruben Mergui
General Motors Computer Science Department General Motors
Herzliya Pituach, Israel Bar Ilan University Herzliya Pituach, Israel
[email protected] Ramat Gan, Israel
[email protected]
[email protected]
Sarit Kraus
Computer Science Department
Bar Ilan University
Ramat Gan, Israel
[email protected]
ABSTRACT KEYWORDS
The successful integration of automation in systems that affect Intelligent Agents, Adaptive Behavior, User Modeling
human experiences requires the user acceptance of those
automated functionalities. For example, the human comfort felt ACM Reference format:
during a ride is affected by the automated control behavior of the
Claudia V. Goldman, Albert Harounian, Ruben Mergui and Sarit Kraus.
vehicle. The challenge presented in this paper is how to develop
2020. Adaptive Driving Agent: From driving a machine to riding with a
an intelligent agent that learns its users’ driving preferences and
friend. In Proceedings of the 8th International Conference on Human-Agent
adjusts the vehicle control in real time, accordingly, minimizing
the number of otherwise required manual interventions. This is a Interaction (HAI' 20), November 10–13, 2020, Virtual Event, Australia.
hard problem since users’ preferences can be complex, context ACM, NY, NY, USA. 8 pages. https://doi.org/10.1145/3406499.3415067
dependent and do not necessarily translate to the language of
machines in a simple and straightforward manner. Our solution
includes (1) a simulation test bed, (2) an adaptive intelligent 1 Introduction
interface and (3) an adaptive agent that learns to predict user’s Advances in sensing and computational technologies pave the
driving discomfort and it also learns to compute corrective actions
way for automating increasing number of driving functionalities.
that maximize user acceptance of automated driving. Overall, we
These engineering solutions result in improved vehicle control
conducted three user studies with 94 subjects in simulated driving
scenarios. Our results show that our intelligent agent learned to and in freeing the human from manually controlling the vehicle
successfully predict how to adjust the automated driving style to at times. Nevertheless, it is essential to recognize that humans are
increase user’ acceptance by decreasing the number of user different, thus preferring different styles of driving when facing
manual interventions. different routes, car occupancy, and driving contexts. Usually,
default, engineering-based driving styles are pre-set to control the
CCS CONCEPTS
correct and safe performance of vehicles. There is a hidden
• Computing Methodologies Artificial Intelligence Intelligent assumption that humans will all accept this style under all
Agents • Machine Learning Applied Computing Driving Control circumstances. However, for different people, the same driving
• Human Computer Interaction maneuver taken with different styles may be perceived as “too
aggressive” by some, whereas others would consider it to be “too
†Corresponding Author cautious” or “uncomfortable”. Integrating these contextual
Permission to make digital or hard copies of all or part of this work for personal or preferences in a learning agent is a challenge. Understanding
classroom use is granted without fee provided that copies are not made or distributed users’ needs and preferences is hard since these preferences are
for profit or commercial advantage and that copies bear this notice and the full citation
on the first page. Copyrights for components of this work owned by others than ACM diverse, can change over time [11] and they are contextual [21,24].
must be honored. Abstracting with credit is permitted. To copy otherwise, or republish,
to post on servers or to redistribute to lists, requires prior specific permission and/or a
This paper attempts to solve this challenge, which requires
fee. Request permissions from
[email protected]. solving three problems: (1) how can an agent interact with human
HAI '20, November 10–13, 2020, Virtual Event, NSW, Australia drivers or passengers to get and interpret their preferences, (2)
© 2020 Association for Computing Machinery.
ACM ISBN 978-1-4503-8054-6/20/11…$15.00 how can this agent learn from these preferences and driving
https://doi.org/10.1145/3406499.3415067 contexts to predict discomfort and (3) how can this agent learn to
adjust online the driving style settings of the vehicle it controls to
avoid predicted discomfort. The first problem is hard since people
might have difficulty in expressing their needs in such complex automated control and decreasing the number of manual
contexts as driving. The evaluation of users’ satisfaction may be interventions required to accept this automated behavior.
also very expensive [8] (e.g., setting cameras inside the car,
analyzing the passengers’ video/audio streams). Therefore, it may
be more efficient to rely on inputs expressed by users in natural 2 Related Work
ways enabling them an interaction similar to one they would have The personalization of human-vehicle interactions has been
with a taxi driver. Namely, we would like to develop an agent that studied by researchers and practitioners over the years including:
would be able to interpret requests such as “Go faster” or “You’re the personalization of a car’s climate control system [18], the
too close” to changes in the technical configuration of the car adaptation of the cruise control system [20] and automatic speed
without requiring users to give technical details how the vehicle control [25] to name a few. In the more complex context of
should be achieving these requests (e.g., “use the gas paddle less adjusting a driving style, many car’s settings and their
smoothly” or “limit the acceleration”). Furthermore, we would like interdependencies affect the user experience (e.g., the smoothness
the agent to reduce the need of the human to make explicit of turning the steering wheel, or of pressing the pedals (gas /
comments by dynamically adjusting the cars’ parameters based on brake), acceleration rate), making existing approaches unsuitable
estimation of the human’s preferences. To solve the last two for our task. Automating human-like driving was studied to
problems, we present a novel learning-based agent for the provide personal comfort [3,4]. Our approach is distinct and novel
automatic adjustment of a car’s driving style configuration by since our agent (1) learns a model of human preferences for driving
processing and intelligently reacting to natural inputs from styles, (2) adapts its automated behavior online accordingly, (3) is
drivers or passengers. Our agent, named the Adaptive Car evaluated with real subjects riding a simulated car and (4)
Controller Agent (ACCA), was developed and tested in a state-of- intuitively interacts with humans overcoming difficulties
the-art realistic simulation environment. Through extensive user encountered by drivers, when expressing what they need from the
studies, with 94 human participants, we show that the ACCA can car in technical terms [6]. Natural interfaces [15] are commonly
significantly reduce user’s burden of adjusting the driving style more intuitive for drivers and passengers to use and understand
manually to achieve acceptable satisfaction levels of comfort and can assist in personalizing the interaction [13, 17]. Most
(measured with usability questionnaires and evaluated relevant to our task is the work by Geng et al. [9], who provide a
quantitively with the number of manual interventions required scenario-adaptive driving style prediction ontology. The proposed
through the studies to express discomfort). We have applied a ontology presents how a car’s driving style should adapt to
similar computational approach successfully in the thermal different traffic scenarios to meet most drivers’ expectations.
domain [18]. We developed an intelligent (intuitive to use) However, the proposed ontology is limited to a “generalized
interface for drivers to change the settings of their automotive prediction” as opposed to a “personalized prediction” [19]. Namely,
climate control system, reducing the number of manual the ontology does not provide a car with the means to adapt to
interventions required. This interface was implemented on a each user nor does it provide a way to adapt the prediction in real-
tablet and used by all participants through all experiments, time. Other user studies in simulated driving environments
enabling them to choose what adjustments to make to the driving analyzed driving styles and their effect on different users [1, 2].
style through touching buttons and sliders with intuitive However, these works collected data of user acceptance via
meaning. questionnaires and not by interacting with an intelligent agent in
Our adaptive solution was developed in three stages, each one real-time, as we do. Guna et al. [10] used driving data to predict
contributing an essential component combined eventually to driving styles given users’ activities. Mazzulla et al. [16] studied the
build up a complete adaptive agent solution: (1) Automatically relationship between drivers’ characteristics and driving styles. In
interpretation of user intuitive needs: we trained an all these works, the online adaptation of the driving style is missing
intelligent agent with human data, provided through an adaptive and is presented as the next required step. In the control domain,
intelligent interface, enabling users to express their driving needs Senouth et al. [22] developed a fuzzy rule to adaptively modulate
without stating specific values for all related parameters. The and assist the driver and vehicle torque to keep the lane preferred
agent was able to interpret these human inputs into actual driving by the driver. This solution was evaluated by numerical
control actions. (2) Automatically learning of human- simulations and not by real interactions with subjects as we
preferred driving style settings: our agent learned 3 human- present here. Our work is novel due to the combination of human-
centered driving styles from data collected in the first experiment. machine interactions with machine learning to provide one
(3) Automatically learning and mitigation of user solution to interpret users’ preferences and then realize these into
discomfort prediction: our agent learned to predict driving actual control actions with the aim of increasing acceptance.
discomfort and learned to avoid it in real time, by adjusting the
driving style of the simulated car accordingly. It computed the
3 Simulation Set Up
control actions that attained the highest likelihood of being
accepted by the users under similar driving situations. Our results
showed that our agent adapted its control behavior successfully Our agent, user studies and evaluations were run in a Unity-based
to its users’ expectations, increasing their acceptance of the simulation environment of automated driving. Subjects playing
the role of passengers sit on a physical car seat while watching
three screens that simulate what they could see through the car’s 4. Gap Time - Minimal stopping time to maintain while
windows and mirrors while driving. Users were told they were traveling behind another car. Value: [1, 4]
going to take a taxi-like ride with a simulated automated driver in 5. Forward Approach Gas Smooth - Determines how abruptly
the city of San Francisco. to release the gas pedal when approaching another car.
Value: [0.1, 0.9]
6. Forward Approach Brake Smooth - Determines how hard or
3.1 Simulation Scenarios
soft to press the brake pedal when approaching an object.
We chose an area in San Francisco city for our simulated Value: [0.1, 0.9]
geographical urban area. The real content of the city was 7. Acceleration Rate - The acceleration applied to reach the
transferred into graphical content from videos taken in San target speed. Value: [0.1, 25]
Francisco. Fig. 1 shows the route arbitrarily generated in the city. 8. Lane Centering - Determines the location of the car relative
Using this route, we designed four driving scenarios. Each to the center of the lane. Value: [0.1, 0.9]
participant experienced the same route with all eleven events, 9. Turn Speed - Determines the desired speed when
performing turns. Value: [8, 40]
four times in random order (each simulated ride took around 5
10. Maximum Speed - Determines the maximum speed of the
minutes). The events, distributed along the route (see Fig. 1) car on an unobstructed road. Value: [10, 50]
include common urban events such as pedestrian crossings, traffic
jams, a jaywalker suddenly crossing the street or a cyclist riding Any combination of values to these parameters would result in
next to the car, approaching a jam, driving in a jam or open road, (slightly) different driving styles. Table 1 presents two basic
encountering a car leaving its parking or lane, encountering driving styles, calm and active, that we defined after having tested
hazards on road. These events were predefined to provide a rich them in the simulator. These styles will serve as the initial default
driving context similar to real-world events. Each one of the four driving styles in the first experiment reported below. Subjects in
rides each participant experienced, differ in the settings assigned our experiments, see the traffic on the road and see and hear the
to each one of the eleven events, creating different driving effects of their own vehicle driving through the screens and
contexts. We will examine the users’ reactions and desired speakers, as they would do if they were sitting in a seat next to a
changes to the car’s driving style in these scenarios. driver in a regular car. The goal of our agent is to learn to adjust
driving styles to those preferred by humans in real time.
Parameter Name Calm Active
Gas Smooth 0.9 0.1
Brake Smooth 0.8 0.1
Gap Distance 10 3
Gap Time 3 1
Forward Approach Gas Smooth 0.9 0.2
Forward Approach Brake Smooth 0.8 0.2
Default Acceleration 4 25
Maximum Speed 16 50
Lane Centering 0 0
Turn Speed 13 34
Table 1: Basic (Default) Driving Styles
Figure 1: Simulator Route. Numbers indicate the locations 3.3 Human Agent Interactions
of the events.
Adjusting the values of driving parameters would be easy if users
3.2 Driving Styles could tell explicitly what they need in the language of the driving
control system to attain driving comfort. However, this is not the
A car's driving style is represented as a vector of driving case. In preliminary trials, participants were asked to express
parameters values. These parameters correspond to the control themselves as they would to a friend who is driving or a taxi
settings in the Unity simulator. We focused on the following ones, driver. We noticed that participants were able to distinguish
that affect the simulated driving behavior: between the different driving styles and were able to discuss them
1. Gas Smooth - Determines how hard or soft to press the gas in terms of their perceived safety and enjoyment. However, it
pedal. Value: [0.1, 0.9]
turned out that participants were not able to satisfactorily express
2. Brake Smooth - Determines how hard or soft to press the
their preferences in terms of parameter values, resulting in many
brake. Value: [0.1, 0.9]
3. Gap Distance - Minimal distance to maintain when user inputs and general dissatisfaction, although they fully
approaching an object. Value: [3, 17] understand the role of each parameter. Specifically, participants
were unable to determine which parameter they should change
and to what extent to bring about the desired change. Moreover, driving settings (that the agent will also log as training data).
we noticed that participants express different expectations based When the agent acted in adaptive mode, changes to settings were
on road conditions and context (e.g., in a traffic jam vs an open also made when the agent proactively predicted human
road). Specifically, while it is reasonable to assume that users can discomfort and the agent decided on the changes to make to the
distinguish between comfortable or not (e.g., feeling safe or in driving parameters based on the learned models.
danger), it is unreasonable to assume that non-expert users would
In the next sections, we describe the three experiments run with
be able to quickly manually configure the above parameters. To
the adaptive driving agent. In all, we evaluate the performance of
that end, following these preliminary trials, we identified the
the agent by quantifying the number of human interventions
following 8 terms which people often use to express their
needed to attain a comfortable ride. All data collected included the
preferred driving style: 1) More Speed; 2) Less Speed; 3) More Gap;
vehicle dynamics, driving contexts and subjects’ inputs if
4) Less Gap; 5) More Sport; 6) More Comfort; 7) More to Right;
provided.
and 8) More to Left. It is therefore our goal in this paper to develop
an automated agent that is capable of intelligently translating
these natural expressions to the desired set of values to assign to 4 Default Driving Agent
the technical parameters (Section 3.2). Fig. 2 shows the interface
we implemented on a Samsung tablet for getting inputs from real The goal of the first experiment was to evaluate how many
users during the experiments. Users could express their desired manual corrections would be requested by human subjects to
changes in driving to the experimenter and the control agent adjust a default driving style during a set of simulated rides. Our
through this interface by resizing the circle, relocating the circle hypothesis was that humans are different and therefore driving
(4 directions) or by moving the sports slider. The users did not contexts will affect the preferred style of driving. We recruited 30
have to assign a value for the change requested, just the desired subjects (17 males and 13 females), ranging in age from 21 and 50
direction of change. Subjects would sit on a car seat and will (avg. 33, s.d. 7.02). Participants were told that they were going to
observe 3 wide screens showing what a passenger would see from take a ride in a simulated taxi in San Francisco for 4 laps driven
the vehicle cabin. All rides occurred in the simulator screens, so by a simulated automated driver. All subjects started 2 rides with
the experience was safe and did not incur any risks to the the default calm driving style and 2 more rides with the aggressive
participants. Driving settings was always kept under safety style as in Table 1 (all runs were balanced). Users interacted with
constraints. the simulated vehicle through the adaptive intelligent interface
(see Fig. 2). When subjects entered any comment (by using the
tablet), the experimenter paused the simulation and asked the
subject for his actual intention. Then, the experimenter adjusted
the driving parameters until a desired changed was achieved (e.g.,
when the comment was “The slowing down was harsh”, the
correction included changing the values of the “Brake Smooth”
and the “Forward Approach Brake Smooth” values). Any request
for driving corrections remained in effect until the end of the
current two rounds. A new driving style was implemented in the
next two rounds. Fig. 3 shows a total of 633 comments received
from the subjects (avg. of 21.1 per participant, s.d., 9.48); with
26.7% of the comments being related to the events we predefined
(these comments were provided up to 7 seconds following an
Figure 2: Adaptive Driving Agent: Natural Interface event). For example, when a jaywalker crossed the street in front
of the car, many participants commented “Less Speed” since the
3.4 The Adaptive Control Agent car was perceived to be approaching the walker too fast (despite
having enough time to stop).
The ACCA agent we developed was able to control the simulated
vehicle through the route we defined. The agent could operate in From the usability questionnaires we collected, we found that
two modes: fixed, or adaptive. The agent was always initialized 66.66% of the subjects mentioned that the intelligent interface was
with a driving style vector that determines the ranges of values of very easy to mostly easy to use (average score of 3.2 out of 10, the
the driving parameters. The simulated vehicle applies these lower the better). The subjects score the match between the
parameters to create the simulated physical dynamics of the driving corrections and their intent high with an average score of
driving context. In the adaptive mode, the agent could change the 8.1 out of 10 (the higher the better).
driving settings proactively during the ride, based on its learned
models of the users’ preferences. Moreover, the agent could
interact with the human subject, riding in the simulated vehicle.
If the agent received external inputs from a subject through the
natural interface, then the experimenter would interpret this
input to the agent and instruct a set of changes to be made to the
Figure 3: Total Manual Corrections Requested per Rides
Laps Figure 4: Human Data-Driven Driving Clusters
5 Human Data-Driven Agent
Our hypothesis was that the number of manual corrections can be
reduced when users choose what driving style they prefer.
Moreover, they chose from styles learned from the human-data
collected in experiment 1. This data reflected the driving settings
that converged towards the end of each round of experiment 1
when the user did not make any further comments. We tested
clustering this data to find the densest types of driving settings
(i.e., all data points in one cluster that have the shortest distance
from the centroid). That is, we scored a clustering method with
Table 2: Human Data-Driven Driving Style Profiles
the standard density measure that computed the average of
distances between items inside the cluster from their centroid and
In experiment 2, we recruited 30 new subjects (16 males and 14
then the average among clusters. Let ‘m’ be the number of
females), ranging in age from 23 and 47. The procedure of
clusters, ‘x’ be a vector pointing to the data point and ‘c’ be a
experiment 2 differs from that in experiment 1 in the users
vector pointing to some centroid. Then the distance ‘di’ to the
choosing the initial (learned) driving styles (in experiment 1, the
centroid can be defined as: 𝑥⃗ − 𝑐⃗ and the density measure is initial driving styles were set as default styles, all participants
the average of this value over the m clusters. The x vector experienced the same default styles with counterbalanced order).
comprised (1) the driving style parameters at the end of rounds 2 In this experiment, participants were asked to choose a driving
and 4, (2) the number of each type of corrections made, (3) style they would prefer in a taxi-like ride. They could choose a
averages of speed, acceleration and jerk. Fig. 4 shows the calm or sportier style or one in between these to reflect the three
clustering algorithms tested (K-means and DBSCAN [14,7]) and styles learned by our clustering algorithm. A reduction of 42% in
their corresponding scores (K-means was tested for various values the number of manual corrections was indeed attained by getting
of k: values equal to 2 and 3 are included in the table, larger values only a total number of 367 corrections from the 30 subjects (i.e.,
were not found to lead to better clustering solutions). Note that on average, subjects requested 12.2 corrections). We noted that
the types of corrections provided do not characterize the styles, even in a simulated study as we run, different users had different
but the driving dynamics do. DBSCAN was too sensitive to small number of comments, meaning some are better with some style
changes in its parameters; it did not find a balanced division of chosen and some requested some additional adjustments (some
points to styles. The winning clustering algorithms was K-means subjects had only a few corrections, while others had as many as
(on inputs 1 & 3); this is consistent with results presented in [24]. 21 comments).
The novelty is that the styles were learned from human data rides
that converged (see Table 2). Normal is situated between the two From the usability questionnaires we collected, we found that the
others. All scores are statistically significant different (tested with subjects gave an average score of 3.2 (out of 10) to the easiness of
ANOVA). use of the adaptive interface (the lower the better). The subjects
score the match between the driving corrections and their intent
high with an average score of 7.9 out of 10 (the higher the better).
6 Adaptive Driving Agent Solution experiment 2 (a total of 117,100 data points) and changing the
number of filters and their size, improved the accuracy to 95.96%
Our end goal was to show how an adaptive agent can improve
in training and 95.44% in testing with an AUC reaching 0.85. This
human driving-comfort, by adjusting the automated driving
retrained CNN could anticipate a user’s comment by 2.5 seconds.
settings in real time. We developed such agent that first, learned
[Online] Adaptation - Every half second the simulator sent data
successfully a model of human discomfort from driving. Then, the
(time, position, driving settings, acceleration, jerk and predefined
agent learned what actual correction should be executed online,
events) to the agent. Every 5.5 seconds of simulation, the logs are
once discomfort is predicted. Our hypothesis is that when users
processed into the 24 features that activate the CNN to predict the
choose their preferred initial driving style (from those learned
current user’s driving discomfort (see Fig. 5). If the agent predicts
from human data) and further interact with an agent that adapts
a state of discomfort, then the agent searches its training data set
its driving behavior to their expected preferences, users will be
for corrections already executed in situations like the current one
intervening the least, compared to the results in the previous
(see Fig. 6). The 9 samples closest to the current state are found and
experiments. The same experimental procedure was applied with
the correction with the highest probability (max vote) is chosen.
the adaptive agent version implemented this time.
For example: let ci (i = [1,9]) denote the 9 data points found closest
[Offline] Discomfort Model - We first pre-processed the to the current state; then without loss of generality assume: c1-
collected data such that each half a second time frame was 2=More Speed, c3-9=More Sport. Then, with probability of 7/9,
associated with the next set of 24 features: More Sport will be chosen and More Speed, with probability of 2/9.
1. Front Distance To - the distance from the car in front Still, the user can enter their input using the interface at any time
2. #Surrounding Cars - Number of cars in a fixed radius (e.g., to reject the correction performed by the agent).
3. #Surrounding Cars (Adaptive) - Number of cars in a speed- To evaluate the adaptive agent performance, we recruited 34
dependent radius subjects (19 males and 15 females), age range in 25-52. Fig. 7 shows
4. Speed - Current speed of the car (Km/h) the results comparing the 3 conditions tested; error bars indicate
5. Acceleration - Current acceleration of the car (km/h2)
standard error. We can clearly see that (1) the use of human data-
6. Avg. Speed - average speed of the car for the last 8 seconds
driven driving styles brings about a significant decrease in the
7. Avg. Acceleration (calculated the same way as above)
8. Lateral Acceleration (m/s2) number of modifications made by the users, p < 0.05 (i.e., 12.2
9. Longitudinal Acceleration (m/s2) corrections on average vs. 20.9 when default driving styles were
10. Lateral Jerk (m/s3) initialized with no user choice). (2) the adaptive agent successfully
11. Longitudinal Jerk (m/s3) reduced this number compared to both other conditions in a
12. Is Max Speed Reached? (1/0) statistically significant manner, p < 0.05 (i.e., only 7.4 corrections
13. Driving Behind Another Car? (1/0) on average vs. 12.2 were required for the participants to achieve
14. – 24. 11 Predefined Events acceptable driving comfort). The statistical analysis was
performed using an ANOVA test followed by post-hoc t-tests
We chose 11 timeframes (equal to a total of 5.5 seconds) in a comparisons with Bonferroni correction. On average, our
moving-window fashion to construct the training instances since adaptive agent performed 19.7 autonomous changes to the driving
users’ inputs are not instantaneous. Each instance is classified as settings during the ride (s.d. 6.3). On average, users accepted 16.2
satisfied (1) or unsatisfied (0) to represent the users’ comfort from of these (accepted means that the agent predicted discomfort and
driving with that vector assignments (SMOTE [5] was used to consequently adjusted the driving settings even prior to the
artificially balance the data set). We built classifiers to predict participant actually asking for these changes). On average, users
when these features’ settings will result in driving-discomfort for corrected the agent only 3.75 times (meaning even when the agent
the user. Driving discomfort is understood as an event when the predicted discomfort and adjusted the settings, the user either did
participant provides input to make an adjustment to the current not agree with the prediction or with the settings adjustment done
driving settings. While the participant does not provide any input automatically). Finally, on average, users gave 3.65 additional
to adjust these settings, we assume that the participant is corrections (that the agent did not predict discomfort accurately).
comfortable with the driving style experienced. We measured the The number of requests depends on the initial driving style (see
quality of these classifiers with the standard Area Under the Curve Fig. 8) and the time passed from the beginning of the drive.
(AUC) score [12]. Using data from experiment 1 as a training set,
we evaluated different prediction models [23]. Random Forest was From the usability questionnaires we collected, we found that the
too simple to capture the dependencies between the driving subjects gave an average score of 3.6 (out of 10) to the easiness of
settings and discomfort. Also, Linear Regression did badly since use of the adaptive interface (the lower the better). The subjects
our data is not linearly separable (due to lack of space the graph is score the match between the driving corrections and their intent
not included). However also the Multi-layer perceptron could not high with an average score of 8.6 out of 10 (the higher the better).
predict well. So, we evaluated networks that can capture the time
sequence relationships in the data. CNN resulted as a better
predictor than the Long-Short-Term Memory. Table 3 summarizes
the AUC scores attained by all predictors tested. Increasing the
training set with data from experiment 1 with data collected in
Figure 7: Average number of manual comments in all tests
Table 3: Predicting Driving Discomfort
Figure 8: Average number of manual comments per chosen
Figure 5: Adaptive Driving Agent Behavior: Discomfort
driving style
Prediction
7 Conclusions
We introduced an automated agent for adapting driving profiles
to users and contexts to reduce human driving discomfort. Human
discomfort was expressed by the participants each time they
provided input to adjust their current driving settings. Our agent
decreased the number of manual interventions required to correct
driving settings. We also introduced a new approach for human
modeling, based on the Convolutional Neural Network (CNN)
trained on data obtained through an adaptive intuitive interface.
Using K-means clustering and the CNN, we showed that this
algorithm can be used in training supervised deep network
models. We conclude that we can successfully integrate human
models of preferences into the automated control systems to
improve their utilization and effectiveness. Instead of a unilateral
interaction between a driver and an automated vehicle where the
user just operates this machine, we created a bi lateral interaction
where the machine is aware of its user. The machine learns from
Figure 6: Adaptive Driving Agent Behavior: Discomfort users’ inputs, it predicts users’ needs and proactively adjusts its
Mitigation
own settings to increase user satisfaction and acceptance. The
complete AI agent system together with the novel adaptive
interface were tested and evaluated successfully through 3 user [13] J. Hwang et al. “Expressive driver-vehicle interface design”. Procs. of Designing
Pleasurable Products and Interfaces, page 19. ACM, 2011.
studies covering a total of 94 human participants in a simulated [14] A. K Jain et al. Algorithms for clustering data, volume 6. Prentice hall Englewood
set up of automated driving scenes. Cliffs, 1988
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Transportaton Research Procedia, 27:945–952, 2017.
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based ultimodal driver displays”. Procs. of the 33rd Annual ACM Conference on
Human Factors in Computing Systems, 2015.
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