A pilot study was completed to verify the feasibility of the driving simulator for use in novice driver training. A total of 12 Clemson University students were invited to complete the initial testing of CATS. The students were between 23 and 27 years old which corresponds to an at risk population group (Christian et al., 2012). Nine of the students (all males) had over two years of driving experience. Drivers were first allowed to drive on a simple track to gain the feel of the simulator. When they felt comfortable, the drivers completed the pre-simulation questionnaire. It contains 10 questions; five basic driving knowledge questions worth 20 points and five driving attitude questions not scored. The total score is 100 points. The driver then completes a two-lap drive on the simulator. Before each of the four scenarios, information will be displayed on the screen to inform the driver of the situation ahead. After the driver has passed each scenario, a simple summary was shown on the screen to inform the driver of their performance. After the first lap, driving rate information was displayed on the computer screen. The driver could return to the main menu to find specific scores for each scenario by looking
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under the score menu. The driver then watched a five-minute instructional video on how to drive correctly in order to pass each scenario and afterwards drove the same track again. This time, the score was used to rate their driving performance.
The complete pilot study data is summarized in Table 2.5. One-third of the drivers had held their driver's license for less than two years and do not have any formal driving education experience. However, two-thirds of all the drivers rated their skills above average, and only one driver rated his driving skill as fair. For the pre- and post- simulation questionnaire, five drivers received a perfect score, four drivers increased their knowledge scores, and two drivers' knowledge scores decreased. Overall, a 5% increase was realized after the drivers completed the driving simulator training. The results of the driving scores for the first run and second run have also been listed in the Table 5. Six of the twelve drivers scored lower on the second run of the simulator than on the first run. For five of these six drivers, the difference between the scores of the first and second run was less than 5%, indicating that the driving simulator did not improve their performance. The remaining drivers scored 20% lower on the second run than on the first run, and performed notably well on the first run. The driver in question had three years of driving experience and had completed a driver's education course. His exceptional performance on the first run testifies to his ability as a competent driver; however, on the simulation he tended to drive aggressively and test the limits of the vehicle dynamics after familiarizing himself with the scenarios presented in the simulation. This behavior can account for his low score on the second run. The other six drivers scored higher on the second run than on the first one; four of them scored 18% higher while two of them
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scored 30% higher. The overall results are an average increase in driving performance from the first run to the second run.
The drivers' ratings are based on the scores of the second run, and are consistently lower than the driver's self-ratings. This discrepancy suggests that many drivers overestimate their driving skills. The data for two subjects (2, 12) are highlighted in Table 2.5. Although both drivers are 25 years old, they have drastically different levels of driving experience (0-2 years vs. 6-10 years) and both scored higher on the second run than on the first run. Subject 2 rates himself as an “excellent” driver while the simulation rates him as merely a “good” driver. While the score is in fact “good”, subject 2 exhibits over-confidence in his driving ability. Subject 12 is a novice driver with less than 2 years of driving experience and no background in driver's education. His driving scores increased by 13 points, indicating a marked increase in driving performance. In both cases, the driver performance benefitted from the automotive simulator exercises.
Table 2.5: Pilot study results for twelve human test subjects using the CATS system Subject Age Years
Driving Self Rating Driving Education Pre Test Score 1st Run Driving Score (DS) 2nd Run Driving Score (DS) Driver Rating (DR) Post Test Score Knowledge Gain (%)
1 27 3-5 Excellent Yes 100 86.75 66 Fair 100 0
2 25 6-10 Excellent No 100 61.25 80 Good 100 0
3 21 6-10 Good Yes 80 84.75 80 Good 100 20
4 24 3-5 Good No 60 45 47.5 Dangerous 80 20
5 24 6-10 Excellent Yes 100 54.75 61.25 Fair 100 0
6 23 0-2 Average Yes 60 59.25 55 Dangerous 100 40
7 26 6-10 Average Yes 100 79.25 76 Average 100 0
8 28 11-20 Good Yes 80 74.75 73.75 Average 100 20
9 23 0-2 Average Yes 100 62.25 58.5 Dangerous 80 -20
10 27 3-5 Good Yes 100 19 54.25 Dangerous 80 -20
11 23 0-2 Fair No 80 21.5 65.5 Fair 80 0
12 25 0-2 Good No 100 71.25 84.25 Good 100 0
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2.5 SUMMARY
Driving a vehicle is a dangerous undertaking for all drivers; especially for novice drivers which represents the highest source of injury and death for this age group. To address this problem, a driving simulator education system was developed for teaching new drivers how to drive safely. Twelve individuals were invited to participate to a small pilot study. The participants answered ten pre-test questions before driving the simulator, and then ten post-test questions after driving the simulator. In the simulator, they drove the same lap twice. While they were driving, data was collected and used to rate their driving performances. Results show that their driving rate improved on the second lap by 6.8%, which suggests that this driving simulator can help improve novice drivers' performances. After each simulation run, a detailed table appeared on the screen, providing insightful information on which skills the drivers may need to practice. The track and its features have been modified based on suggestions by the participants of the pilot study which will facilitate the comprehensive large scale case study.
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CHAPTER THREE
ASSESSMENT OF AN AUTOMOTIVE DRIVING SIMULATOR TO EDUCATE NOVICE DRIVERS
Novice drivers are more likely to be involved in vehicle crashes than more experienced drivers. Transportation system simulators, such as aerospace, automotive, and rail, have been used effectively over several decades in support of operator training and research studies. The immersive high-end automotive simulators tend to be large- scale, difficult to move, and relatively cost ineffective for widespread deployment. In contrast, a mobile vehicle training system often features simplistic environments which are not readily accepted by teenagers who evaluate the driving experience as compared to commercial video games. Consequently, a need exists for a low-cost portable automotive training system that provides a higher level of realism with superior graphics for novice drivers. In this paper, a turn-key computer system is presented to assist novice drivers in the improvement of their driving skills with performance evaluations. The custom simulator was assessed by 50 participants who answered pre-test and post-test questionnaires and drove the simulated vehicle around a preset course. The participants overall driving score improved 28% with gains on both driving knowledge (questionnaire) and proficiency (test track). The simulator has been proven to be efficient at raising both driving knowledge and skills; the tool set represents an important resource for driver training programs. The next step will be its integration into a nationwide safe driving program to complement in-vehicle instruction with virtual instruction.
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3.1 Introduction
Young drivers, particularly those between the ages of 16 and 23, have more than double the number of car accidents than older drivers (McCartt et al., 2009). Researchers have identified several factors that may cause novice drivers to have more crashes than experienced drivers. First, young drivers have less experience operating vehicles on the roadways and usually overestimate their driving skills (Craen et al., 2011). Second, most young drivers are not as familiar with traffic laws since their past experiences were largely derived as passengers (Dols et al., 2001). Third, novice drivers may inaccurately gauge the speed of cars around them and/or the relative distance between surrounding vehicles (Chan et al., 2010 and Scialfa et al., 2011). Unfortunately, this inexperience may cause them to suddenly decelerate their vehicles and/or change lanes without noticing approaching cars. Finally, young drivers may be more easily distracted by various factors such as roadside advertisements, electronic devices including MP3 players, cell phones, and portable video games, which draw their attention away from the roadway (Green, 2010). Therefore, driver education programs should help novice drivers understand the danger of inexperience and gain critical knowledge and skills through focused classroom, in-vehicle, and simulated instructions.
Driver training laws and programs have existed for many years around the world. The Graduated Driving License (GDL) Program, first introduced in 1996 in Florida, has been adopted throughout the United States in various forms (Ferguson, 2003). The GDL program attempts to increase young driver safety while decreasing their crash rates through restricted motor vehicle operation. Young drivers need to initially pass the
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standard written and in-vehicle driving tests. The written test requires drivers to answer basic questions designed to evaluate their knowledge of proper vehicle operation, while the vehicle driving test assesses the driver’s mastery of fundamental driving skills. However, a GDL program license imposes age-based restrictions on motor vehicle operation. For example, the driver may only operate their vehicle at certain times and without passengers below a prescribed age. As the young driver matures, these restrictions are decreased until the individual is fully licensed. Although the current GDL program has been successful in educating novice drivers, a number of limitations exist with the overall driver licensing process. First, young drivers typically learn how to operate motor vehicles from their parents; so the teaching effectiveness depends on the parents’ skills. Second, the driving proficiency test commonly occurs during daytime hours on local roads with minimal traffic, so the driver’s proficiency is not fully evaluated on all roads or during nighttime. Consequently, a need exists to better train novice drivers.
Virtual driving education has the potential to become an important tool for training young drivers. Racing games are one type of a virtual driving simulator which has flourished over the past two decades. Some video games, such as “Grand Turismo 5” and “Need For Speed”, are quite adept at mimicking real world conditions and pose the question of whether it would be possible to educate novice drivers using immersive automotive simulators. Young drivers are more likely to spend time practicing a driving skill if it is also delivered in an entertaining manner (Wahlberg, 2010). Furthermore, a greater variety of driving scenarios can be created within a simulation environment much
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easier than they can be implemented at a test track. The scenarios implemented in a simulator are also inherently safer than their real world equivalents and allow risky scenarios such as two wheels off, excessive speeding, driving too close to a lead vehicle, using a mobile phone while driving (including text messaging), and violating traffic rules. Based on this concept, driving simulators designed specifically for training young drivers have been developed (Kemeny, 2003). Through the efforts of the researchers, virtual driving simulators to train young drivers have become more effective and practical (Park and Lim, 2003). Norfleet et al. (2009) applied a large scale virtual driving simulator to improve driving skills. However, since the simulator was fixed in a psychology laboratory, it was not practical for training people off the Clemson University campus. Thus, it became apparent that a more portable version of the driving simulator would be ideal.
The Clemson Automotive Training System (CATS), a portable driving simulator (shown in Figure 3.1), has been developed to help improve driving experiences and reduce potentially dangerous behaviors (Yao et al., 2013). The training system combines three aspects: a pre-test questionnaire, four driver modules, and a post-test questionnaire. First, the drivers answer ten multiple choice questions prior to driving. Second, they drive on a virtual test track, in which four modules evaluate different aspects of the drivers' behaviors and reactions to various scenarios. An assessment system records different types of data in the background to identify and analyze the drivers’ performances. Third, the driver completes a post-test questionnaire after completing the modules. Both the pre- test and post-test questionnaires are recorded and compared. The scores of the first and
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the second driving runs are combined to create a total score. A total of 50 people have participated in this study and the results have shown an overall score improvement of 28% in their driving performance.
Figure 3.1: Portable Clemson Automotive Training System (CATS) with seat belt, standard human / vehicle interface, screen display, speaker and the host PC workstation
The remainder of this paper is organized as follows: Section 2 introduces the Clemson Automotive Training System, including the hardware, software, features, and track scenarios. Section 3 describes the process of completing the virtual driving test and analyzing the data. Section 4 contains the conclusion. The six Appendices present the human test subjects’ results (Appendix A and B), demographic questionnaire (Appendix C), the scoring metrics (Appendix D), and Nomenclature list (Appendix E).