Intelligent Speed Adaptation Systems Research Articles

Employing a multi-sensor fusion array to detect objects for an orbital transfer vehicle to remove space debris

PurposeThis article takes into account object identification, enhanced visual feature optimization, cost effectiveness and speed selection in response to terrain conditions. Neither supervised machine learning nor manual engineering are used in this work. Instead, the OTV educates itself without instruction from humans or labeling. Beyond its link to stopping distance and lateral mobility, choosing the right speed is crucial. One of the biggest problems with autonomous operations is accurate perception. Obstacle avoidance is typically the focus of perceptive technology. The vehicle's shock is nonetheless controlled by the terrain's roughness at high speeds. The precision needed to recognize difficult terrain is far higher than the accuracy needed to avoid obstacles.Design/methodology/approachRobots that can drive unattended in an unfamiliar environment should be used for the Orbital Transfer Vehicle (OTV) for the clearance of space debris. In recent years, OTV research has attracted more attention and revealed several insights for robot systems in various applications. Improvements to advanced assistance systems like lane departure warning and intelligent speed adaptation systems are eagerly sought after by the industry, particularly space enterprises. OTV serves as a research basis for advancements in machine learning, computer vision, sensor data fusion, path planning, decision making and intelligent autonomous behavior from a computer science perspective. In the framework of autonomous OTV, this study offers a few perceptual technologies for autonomous driving in this study.FindingsOne of the most important steps in the functioning of autonomous OTVs and aid systems is the recognition of barriers, such as other satellites. Using sensors to perceive its surroundings, an autonomous car decides how to operate on its own. Driver-assistance systems like adaptive cruise control and stop-and-go must be able to distinguish between stationary and moving objects surrounding the OTV.Originality/valueOne of the most important steps in the functioning of autonomous OTVs and aid systems is the recognition of barriers, such as other satellites. Using sensors to perceive its surroundings, an autonomous car decides how to operate on its own. Driver-assistance systems like adaptive cruise control and stop-and-go must be able to distinguish between stationary and moving objects surrounding the OTV.

How to take speed decisions consistent with the available sight distance using an intelligent speed adaptation system

Travelling at excessive speed increases the risk of having a road crash. Intelligent Speed Adaptation (ISA) systems might help the driver to make safe speed decisions along road sections with limited visibility. A recently developed ISA system, called V–ISA (Hazoor et al., 2021), is able to estimate the dynamic (real-time) speed limit, based on the prevailing sight conditions and stopping distance. The V-ISA operates in the following three ways: it can (i) display visual information, (ii) alert the driver with a warning sound, and/or (iii) intervene directly to modify and control vehicle speed. The effects of V-ISA on driving performance have yet to be investigated. Thus, the question of whether V-ISA modulates driving speed choice remains open. Here, we assessed the impact of V-ISA variants on driver speed choice. Thirty expert drivers experienced four simulated driving conditions, in which the three V–ISA variants together with the V-ISA off control condition were tested separately. Furthermore, drivers were asked for feedback on the acceptance and usability of the three V-ISA. Our results suggested that V–ISA was effective in mitigating the risks associated with speeding, with relatively high acceptance and perceived usability levels. The results indicate that V–ISA can have a positive impact on road safety by helping drivers to modulate their chosen driving speed.

The pros and cons of Intelligent Speed Adaptation as a restrictive measure for serious speed offenders

In 2011 in the Netherlands a field operational test was performed to investigate the possibility of using restrictive Intelligent Speed Adaptation (ISA) as a penalty system for serious speed offenders. This paper presents the overall results of the research focusing on the pros and cons of the use of ISA as a restrictive measure for serious speed offenders, and on the preconditions for deployment. The results showed that the ISA systems tested have a huge effect on driver behavior and have the potential to improve road safety by reducing the level of speeding, mean speed, as well as the standard deviation of speed. However, there are also cons: the behavioral change in driving behavior was only temporary. In addition the tested technology proved too easy to override, raised issues of equity, and a substantial back office is required when implementing the system for serious speed offenders.

Intelligent Speed Adaptation and driving speed: Effects of different system HMI functionalities

In this paper we study driver behaviour changes when driving vehicles equipped with Intelligent Speed Adaptation (ISA) systems. The primary tool used is a driving simulator. Three different ISA human machine interface functionalities are investigated: informative, warning, and intervening. Data were extracted from the simulator along with questionnaires completed by drivers following each drive. Possible impacts of system functionalities on driver behaviour are studied through appropriate metrics including driving speed, speed deviation, frequency and magnitude of speeding and the empirical cumulative distribution function of speeding. Perceived impacts on drivers are investigated to identify driver attitudes towards the systems as well as possible relations between anticipated and measured behaviour. The study indicates that use of ISA systems, in general, results in the adoption of vehicle speeds that are likely to improve road safety. However, we also found that drivers may misuse ISA systems, potentially resulting in negative road safety effects.

Perceived mental workload, trust, and acceptance resulting from exposure to advisory and incentive based intelligent speed adaptation systems

A 2010 field operational test completed in the United States (US) used an advisory level Intelligent Speed Adaptation (ISA) system coupled with a modest cash incentive to reduce speeding. Each participant drove an instrumented vehicle for a four week period in a naturalistic setting, with the beginning week and final week being baseline periods. The ISA system and incentive were activated for some participants, depending on assignment to experimental conditions, during the middle two weeks of the trials. Driving with the systems, particularly the incentive component, led to a significant reduction in the percentage of time speeding over the posted limit (these results are reported elsewhere). At the end of each week of driving, participants provided ratings of perceived mental workload and completed a “Trust and Acceptance” rating scale after experiencing the incentive and speed warning systems. This paper documents the results of the workload and trust data. As expected, the incentive condition was associated with increased mental demand, temporal demand, frustration, and effort. Unexpectedly, the speed warning did not reduce mental workload of drivers in the incentive condition compared with the incentive only condition. Also counter to our predictions, drivers who experienced the warning without the incentive did not indicate increased mental demand or temporal demand. Trust and acceptance ratings were generally positive for both systems, although the auditory component of the warning was rated unfavorably. Participants who experienced the incentive system rated the speed warning system as less trustworthy than participants who did not experience the incentive, and this finding may partially explain the lack of a reduction in mental workload for participants in the incentive+warning compared with the incentive only condition.

Adapting ISA system warnings to enhance user acceptance

Inappropriate speed is a major cause of traffic accidents. Different measures have been considered to control traffic speed, and intelligent speed adaptation (ISA) systems are one of the alternatives. These systems know the speed limits and try to improve compliance with them. This paper deals with an informative ISA system that provides the driver with an advance warning before reaching a road section with singular characteristics that require a lower safe speed than the current speed. In spite of the extensive tests performed using ISA systems, few works show how warnings can be adapted to the driver. This paper describes a method to adapt warning parameters (safe speed on curves, zone of influence of a singular stretch, deceleration process and reaction time) to normal driving behavior. The method is based on a set of tests with and without the ISA system. This adjustment, as well as the analysis of driver acceptance before and after the adaptation and changes in driver behavior (changes in speed and path) resulting from the tested ISA regarding a driver's normal driving style, is shown in this paper. The main conclusion is that acceptance by drivers increased significantly after redefining the warning parameters, but the effect of speed homogenization was not reduced.

Intelligent speed adaptation—Effects and acceptance by young inexperienced drivers

This study assessed the relative effects of two intelligent speed adaptation (ISA) systems (informative and actively supporting) on simulated driving performance and acceptability in a sample of inexperienced and experienced drivers. Participants drove a series of simulated drives under three conditions: no ISA (control), ISA informative and ISA actively supporting. The informative system significantly reduced speed and was particularly effective in reducing top-end speeds. Comparable reductions were not found for the actively supporting system. Differences in the effectiveness and acceptability of ISA systems were noted across experienced and inexperienced drivers. The ISA systems appeared more effective at reducing speeds for experienced drivers on some road types. Experienced drivers’ subjective satisfaction ratings of the systems also remained constant over the trial, whereas the inexperienced drivers’ ratings changed after experience. There was little evidence that drivers engaged in negative behavioral adaptation and no evidence that subjective workload levels increased with ISA use. Future directions for examining the safety benefits of ISA, particularly for inexperienced drivers, are discussed.

Enhancing speed management by in-car speed assistance systems

Intelligent speed adaptation (ISA) systems support drivers to comply with the legal speed limits. This functionality is expected to become increasingly important in speed management if integrated well with more traditional speed management measures. Based on state-of-the-art scientific literature, this study describes the current knowledge on the effects of ISA and the willingness of stakeholders to adopt ISA. Although the expected effects of the various ISA types are promising and stakeholders are willing to adopt ISA, the large-scale deployment of ISA is still lacking. The main challenges with respect to ISA deployment relate to its social and political feasibility. Overall, a more active role of public authorities is recommended on ISA deployment, especially for ISA systems that actively intervene in the driving task.

Incorporating intelligent speed adaptation systems into microscopic traffic models

Intelligent speed adaptation (ISA) systems are incorporated here into microscopic traffic models; Gipps' car-following model is discussed and the appropriate model parameters that need to be modified and additional ones that may need to be introduced are investigated. Driver behaviour under three different functionalities of ISA, namely informative, warning and intervening, is investigated through a driver simulator experiment. The impact of ISA systems on driver behaviour is a complex matter because it varies both among drivers and under different scenarios. The main parameters that capture the ‘reaction’ to the system are identified and are quantified through model parameters. These are driver speed, acceleration, deceleration, reaction time and effective size of the vehicle, and are estimated following the analysis of the simulator data. The resulting values confirm the necessity of parameter modification. The analysis performed for the incorporation of ISA into the traffic model indicated that a prerequisite of successful implementation is a deep understanding of the model parameters and dynamics.

Development and evaluation of an advanced intelligent speed adaptation system

Intelligent speed adaptation (ISA) systems are in-vehicle systems that have the capability of either warning drivers of adverse speeding behaviours or limiting them from exceeding a prevailing speed limit or advisory. The former, called the warning—informational ISA system, has been noted to be ineffective in reducing speeding while being acceptable to drivers. However, the limiting ISA system, called the mandatory ISA system, has been effective in reducing speeds, yet highly unacceptable from research conducted largely in Europe. These tests of ISA systems have shown that there is a significant consumer acceptance hurdle on the one hand, and an efficacy hurdle on the other. This paper presents the results of a driving simulator experiment that tested the acceptance and effectiveness of a new type of ISA system, called the advanced vehicular speed adaptation system (AVSAS). AVSAS was designed as a speed-management system, rather than a speed-limiting system, based on individual driver speeding behaviours under different roadway scenarios. Statistical analyses were conducted to determine the effectiveness of AVSAS while a survey was used to gauge the acceptance of the system. The results showed that AVSAS contributed to the reductions in the drivers' speeds for two roadway scenarios. The survey results revealed a higher acceptance rating of AVSAS.

Map matching for intelligent speed adaptation

The availability of Global Navigation Satellite Systems (GNSS) enables sophisticated vehicle guidance and advisory systems such as Intelligent Speed Adaptation (ISA) systems. In ISA systems, it is essential to be able to position vehicles within a road network. Because digital road networks as well as GNSS positioning are often inaccurate, a technique known as map matching is needed that aims to use this inaccurate data for determining a vehicle's real road-network position. Then, knowing this position, an ISA system can compare speed with the speed limit in effect and take measures against speeding. An on-line map-matching algorithm is presented with an extensive number of weighting parameters that allow better determination of a vehicle's road network position. The algorithm uses certainty value to express its belief in the correctness of its results. The algorithm was designed and implemented to be used in the large scale ISA project ‘Spar på farten’. Using test data and data collected from project participants, the algorithm's performance is evaluated. It is shown that the algorithm performs correctly 95% of the time and is capable of handling GNSS positioning errors in a conservative manner.

Effectiveness and Acceptance of Adaptive Intelligent Speed Adaptation Systems

Intelligent speed adaptation (ISA) systems face significant consumer acceptance hurdles that limit the likelihood of widespread adoption, particularly in the United States. However, if these systems are designed as speed management systems rather than speed limiting systems, with adaptability to individual driving behavior, they may be more likely to meet with consumer acceptance. The results of a fixed-based driving simulator experiment that tested the acceptance and effectiveness of a new type of ISA, called an Advanced Vehicular Speed Adaptation System (AVSAS), are reported. The results of the experiment showed that AVSAS resulted in reductions in driver speeds across a range of roadway types. AVSAS is a speed management system that adapts to an individual driver's speed behavior and the current driving situation. AVSAS resulted in an average reduction of 5% of the maximum speeds and 3% of the average speeds of the drivers on four road segments. As expected, AVSAS did not reduce driver speeds as much as the mandatory control ISA system, and the experiment confirmed the results of tests conducted on ISA systems largely in Europe. Conversely, the results revealed that more participants were willing to purchase AVSAS compared with the information or mandatory ISAs. Although these results show the promise of a trade-off between system effectiveness and acceptability that has been missing in mandatory and information ISA research, AVSAS suggests that a range of ISA system design requirements could encourage the adoption of ISA systems in the United States.

Discussion of a new adaptive speed control system incorporating the geometric characteristics of the roadway

In this paper, different control systems are reviewed, classified and analysed as well as intelligent speed adaptation systems (ACCs, ISA), their objectives and prototypes implemented in different countries. After this discussion, an adaptive speed control system, based on the geometric characteristics of the road, is presented. The SAGE system, developed in the INSIA (University Institute for Automobile Research), consists of a real time electronic device for the driver information about the optimum driving velocity, taking into account driving safety criteria. These criteria have been defined considering the geometric characteristics of the road and the dynamic behaviour of the vehicle. The prototype developed is presented, and also its strategy and functions.

Network effects of intelligent speed adaptation systems

Intelligent Speed Adaptation (ISA) systems use in-vehicle electronic devices to enable the speed of vehicles to be regulated automatically. They are increasingly appreciated as a flexible method for speed management and control particularly in urban areas. On-road trials using a small numbers of ISA equipped vehicles have been carried out in Sweden, the Netherlands, Spain and the UK. This paper describes the developments made to enhance a traffic microsimulation model in order to represent ISA implemented across a network and the impact of this on the networks. The simulation modelling of the control system is carried out on a real-world urban network, and the impacts on traffic congestion, speed distribution and the environment assessed. The results show that ISA systems are more effective in less congested traffic conditions. Momentary high speeds in traffic are effectively suppressed, resulting in a reduction in speed variation which is likely to have a beneficial impact on safety. Whilst ISA reduces excessive traffic speeds in the network, it does not affect average journey times. In particular, the total vehicle-hours travelling at speeds below 10 km/hr have not changed, indicating that the speed control had not induced more slow-moving queues to the network. A statistically significant, eight percent, reduction in fuel consumption was found with full ISA penetration. These results are in accordance with those from field trials and they provide the basis for cost-benefit analyses on introducing ISA into the vehicle fleet. However, contrary to earlier findings from the Swedish ISA road trials, this study suggested that ISA is likely to have no significant effect on emission of gaseous pollutants CO, NOx and HC.

ADVANCED DRIVER ASSISTANCE SYSTEMS: AN OVERVIEW AND ACTOR POSITION

This paper shows some details and acceptability aspects of three types of systems which are part of a comprehensive State of the Art review on Advanced Driver Assistance Systems: Navigation, Advanced Cruise Control & Stop and Go, and Intelligent Speed Adaptation systems. It was concluded that luxury car drivers considered the warning type of Intelligent Speed Adaptation acceptable and expected this to have a positive impact on road safety, and that truck drivers found the navigation functionality most attractive in general, and Advanced Cruise Control & Stop and Go functionality on motorways and rural roads.