Rahul Suryakant Sakhare

Dr. Rahul Suryakant Sakhare

Purdue University West Lafayette, West Lafayette, Indiana, USA
orcid
Transportation Research Engineer, Purdue University

Research Focus & Metrics

Academic Career Length

11Years (2016-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 June 2022 in Safety
Verified
Journal Article
Open access
PDF file
Rahul Suryakant SakhareRahul Suryakant Sakhare
Rahul Suryakant Sakhare
JDJairaj Chetas Desai
Jairaj Chetas Desai
HLHowell Li
Howell Li
MKMischa A. Kachler
Mischa A. Kachler
DBDarcy Bullock
Darcy Bullock
The National Work Zone Safety Information Clearinghouse estimated there were approximately 115,000 work zone crashes with 842 fatalities in 2019. There is broad consensus that it is important for agencies to develop near real-time risk assessment of work zone traffic operations to proactively identify improvement opportunities. Due to the huge spatial distribution and relatively low frequency of crashes, legacy techniques of monitoring crash locations do not scale well for identifying all but the most severe construction zone operational problems. Past research identified hard braking and congestion as strong predictors for crashes in and around work zones. This paper presents scalable methodologies that can be used to systematically analyze hard-braking and speed data obtained from connected vehicles. These techniques have been applied to over 205 billion records in Indiana since 2019. These statewide data analytics are fused into concise graphics to identify work zones with emerging anomalies in congestion and/or hard braking. Weekly screening reports, institutionalized in Indiana for the past two years, provide information for agile agency monitoring and response. Case studies show quantitative changes in work zone performance measures, and corresponding surveillance video images illustrate the significance of these changes. During this period of near real-time monitoring and agile agency response, Indiana interstate crash rates have been reduced by 31% from 2019 to 2021, even though most 2021 interstate traffic volumes have rebounded to pre-pandemic 2019 volumes.

8 September 2021 in Sensors
Verified
Journal Article
Open access
PDF file
JMJustin Anthony Mahlberg
Justin Anthony Mahlberg
Rahul Suryakant SakhareRahul Suryakant Sakhare
Rahul Suryakant Sakhare
HLHowell Li
Howell Li
JMJijo K. Mathew
Jijo K. Mathew
DBDarcy Bullock
Darcy Bullock
GSGopi C. Surnilla
Gopi C. Surnilla
There are over four million miles of roads in the United States, and the prioritization of locations to perform maintenance activities typically relies on human inspection or semi-automated dedicated vehicles. Pavement markings are used to delineate the boundaries of the lane the vehicle is driving within. These markings are also used by original equipment manufacturers (OEM) for implementing advanced safety features such as lane keep assist (LKA) and eventually autonomous operation. However, pavement markings deteriorate over time due to the fact of weather and wear from tires and snowplow operations. Furthermore, their performance varies depending upon lighting (day/night) as well as surface conditions (wet/dry). This paper presents a case study in Indiana where over 5000 miles of interstate were driven and LKA was used to classify pavement markings. Longitudinal comparisons between 2020 and 2021 showed that the percentage of lanes with both lines detected increased from 80.2% to 92.3%. This information can be used for various applications such as developing or updating standards for pavement marking materials (infrastructure), quantifying performance measures that can be used by automotive OEMs to warn drivers of potential problems with identifying pavement markings, and prioritizing agency pavement marking maintenance activities.

31 January 2023 in Vehicles
Verified
Journal Article
Open access
PDF file
Rahul Suryakant SakhareRahul Suryakant Sakhare
Rahul Suryakant Sakhare
YZYunchang Zhang
Yunchang Zhang
HLHowell Li
Howell Li
DBDarcy Bullock
Darcy Bullock
With the emergence of connected vehicle data and high-resolution weather data, there is an opportunity to develop models with high spatial-temporal fidelity to characterize the impact of weather on interstate traffic speeds. In this study, 275,422 trip records from 41,234 unique journeys on 42 rainy days in 2021 and 2022 were obtained. These trip records are categorized as no rain, slight rain, moderate rain, heavy rain, and very heavy rain periods using the precipitation rate from NOAA High-Resolution Rapid-Refresh (HRRR) data. It was observed that average speeds decreased by approximately 8.4% during conditions classified as very heavy rain compared to no rain. Similarly, the interquartile range of traffic speeds increased from 8.34 mph to 12.24 mph as the rain intensity increased. This study also developed a disaggregate approach using logit models to characterize the relationship between weather-related variables (precipitation rate, visibility, temperature, wind, and day or night) and interstate speed reductions. Estimation results reveal that the odds ratio of reducing speed is 5.8% higher for drivers if the precipitation rate is increased by 1 mm/h. The headwind was found to have a positive significant impact of only up to a 10% speed reduction, and speed reduction is greater during nighttime conditions compared to daytime conditions by a factor of 1.68. The additional explanatory variables shed light on drivers’ speed selection in adverse weather environments, providing more information than the single precipitation intensity measure. Results from this study will be particularly helpful for agencies and automobile manufacturers to provide advance warnings to drivers and establish thresholds for autonomous vehicle control.

1 October 2023 in Future Transportation
Verified
Journal Article
Open access
PDF file
Rahul Suryakant SakhareRahul Suryakant Sakhare
Rahul Suryakant Sakhare
HLHowell Li
Howell Li
DBDarcy Bullock
Darcy Bullock
The concept of traffic shock waves was first theorized by Lighthill and Whitham in 1955. The identification of shock wave type and speed in a traffic stream provides critical information about the queue formation and its dissipation. This information can be utilized by various stakeholders for traffic management, emergency response, etc. Such information can also be integrated into the travel time prediction models and real-time route diversions for navigation. Past efforts at identifying shock waves used simulation or analysis based on location-based sensors such as loop detectors. This paper describes scalable methodologies for measuring shock wave propagation using Connected Vehicle (CV) data. The techniques to identify the six different types of shock waves are illustrated through case studies from Indiana highways that use both CV data and the corresponding surveillance camera images. The shock wave speeds for each event are estimated using the linear regression model, with most shock wave speed estimates having a coefficient of determination (R2) of 0.9 or better. Although shock wave speeds vary by traffic flow rates and geometry, the typical backward forming shock wave speeds ranged from 1.75 to 11.76 mph whereas the backward recovery shock wave speeds were observed to be between 5.78 and 16.54 mph. These techniques can be adapted for real-time use to assist traffic management centers with estimating upstream propagation and recovery time. A case study with a car fire is used to illustrate how this shock wave speed data can be used to frame discussions with first responders regarding how reducing incident clearance time can reduce the risk of secondary crashes.

13 September 2019 in Transportation Letters
Verified
Journal Article
Closed access
Rahul Suryakant SakhareRahul Suryakant Sakhare
Rahul Suryakant Sakhare
LVLelitha Devi Vanajakshi
Lelitha Devi Vanajakshi
Travel time information assists road users in making informed travel decisions such as mode choice, route choice and/or time of travel. This study explores the use of GPS data from buses and Wi-Fi and Bluetooth data from a sample of vehicles, for accurate estimation of the travel time of all vehicles on the roadway. A 5.5 km road stretch in Chennai city was selected as study stretch and data were collected for a week’s period. The present study develops models using linear regression and artificial neural network (ANN) techniquesFto estimate stream travel time using bus travel time obtained from GPS. ANN performed better compared to the linear regression for all sizes of segments. Most of the Indian cities have an integrated network of buses traveling on most of the road segments with on-board tracking devices, making this a useful development for real-time travel time estimation.

2 February 2024 in Future Transportation
Verified
Journal Article
Open access
PDF file
Rahul Suryakant SakhareRahul Suryakant Sakhare
Rahul Suryakant Sakhare
JDJairaj Chetas Desai
Jairaj Chetas Desai
ECEnrique D. Saldivar Carranza
Enrique D. Saldivar Carranza
DBDarcy Bullock
Darcy Bullock
International trade is a critical part of the United States economy. Land border crossings between the United States and Mexico accounts for a large proportion of the USD 779 billion in trade between these two countries. Monitoring and managing the operations of these land border crossings is critical for ensuring efficient trade and providing appropriate security. This paper examines the opportunity to use connected vehicle data to monitor the travel time delay of passenger vehicles crossing the border for system level assessment across 26 border crossing locations over an analysis period of 25 days in August 2020. A sample size of 51,341 trips from the US to Mexico and 41,708 trips from Mexico to the US were used in this study. Furthermore, 97% trips to the US and 76% trips to Mexico experienced delays. The average delay was 34 min for trips to the US compared to only 2 min for trips to Mexico. In terms of the predictability of border crossing times, there was also substantial variation by direction. The interquartile range of vehicle delay from the US to Mexico was 2 min, while the interquartile range of delay for vehicles travelling from Mexico to the US was 46 min. Border crossings were also ranked using four performance metrics—trip counts, median delay, delayed trip counts and total delays in vehicle hours. Methods for summarizing delay trends by time of the day and day of the week to identify time windows of interest are also presented. Land border crossing operations have a significant influence on security and economic efficiency. We believe the techniques presented in this paper provide a scalable methodology for providing near real-time factual data on border crossing delays that provide important information for land border transport-managing stakeholders to make informed management decisions that balance security and economic efficiency.