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www.hawkeyeradar.com
USER GUIDEVersion 1.2
AUTOMATED PERFORMANCE MEASURES FOR INTERSECTIONS AND FREEWAYS
Table of Contents
Statistics ModuleUMRR Outstanding FeaturesLog in Reporting Chart Basics
Axes GridColor LegendTime StampTime RangeCustom RangeExport as CSVSave as ImageOn/Off ObjectsFlexible Dashboard
Control PanelSettings Menu
Visualizing DataIntersection Reports
ArrivalsArrivals on RedArrivals on Green
Use Case: Progression Through a Corridor
VolumeVolume/ApproachVolume/LaneVolume/PhaseComposition/Approach
Use Case: Vehicle Classification
5556666677788899
1010101111
121213131415
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Delay and LOSDelay/Vehicle/Phase
Use Case: Long Wait Times and Delay During Off-peak Times
Total Delay/Vehicle/PhaseLevel of Service/ApproachLevel of Service/Intersection
OthersAverage Speed
Use Case: Capturing Vehicle Speeds
Passed on RedOccupancy %HeadwayPurdue Coordination Diagram
PerformancePerformance Overview by Phase
Radar Live ViewReports for Freeways
Volume/FlowTotal VolumeVolume/DirectionVolume/LaneCompositionHeavy Vehicles PercentagePHF/LanePeak Hour Factor/Direction
151516
161719191920
21212223242426282828293030313132
Table of Contents
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HawkeyeTable of Contents
Flow Rate/LaneFlow Rate/Direction
DensityDensity/DirectionDensity/LaneOccupancy%HeadwayGap
SpeedTime Mean SpeedFree Flow SpeedSpeed-Volume Variation
Level of ServiceLOS/Direction
Live ViewsTraffic Events
Traffic InterruptionsWrong Way
333434343536363738383940404041424242
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Version 1.2
PN: 510-00031
September 2019
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Specs
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UMRR Evolved Outstanding Features• The most Advanced Tracking Radar• Truly Universal – serves a variety of applications• Lane Specific Detection• Individual Object Tracking• Flexible Installation• Statistics and Event Trigger Modules
Log in
Open the Hawkeye reporting application through the web link to the radar device. Type in your username and password.
This document has been devised as a practical guide for traffic professionals, engaged in monitoring and managing vehicle throughput across the US road network. It includes step-by-step instructions for each of the key functional aspects of the Hawkeye UI and reporting solution.
Hawkeye is a third generation 3D-UHD UMRR with unprecedented detection and data collection capability. The radar can not only detect vehicles at the stop bar, but also up to 1000 feet away from it. Its ground-breaking technology turns real-time data into reliable decisions for optimal traffic management.
Statistics Module
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Reporting Chart BasicsThe following metrics are common across all reports:
Axes Grid
• X axis – usually depicts the reporting period• Y axis – reflects any other metrics of interest (e.g., count of vehicles,
average speed, delay or as relevant)
Color Legend
• Available on each chart. These explain what the colors in the structure represent
Time Stamp
• Displayed next to the name of each report • Shows the period under monitoring, the resolution – the time bins per which
data will be gathered and the stats refresh interval
Time Range
• Last Hour – 60 min counted backwards from the current time• Today – 24-hour period from midnight of the past date through 23:59 of
the current day• Yesterday – self-explanatory• This Week – Monday – to date• Last 7 days – counted backwards from today’s date• Last Week – Monday through Sunday of the previous week• This Month – as of the 1st of the current month to date
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Custom Range
• Resolution bins – equal time intervals for capturing data according to a measurable temporal pattern. They are further divided into segments to help put a time stamp to events.
• Data Refresh – can be set to the desired frequency for retrieving fresh data from the database.
Export as CSV
• The results displayed on each chart can be exported to a .csv file
Save as image
• Saves the report in a .png format. Convenient for presentations and data sharing.
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On/Off Objects
• Individual phase, lane and approach can be switched on and off on cumulative charts by clicking on the respective checkbox at the bottom of the screen.
Flexible Dashboard
• Multiple reports can be kept open on the screen for simultaneous viewing and comparing data, trends, patterns, etc.
The screen header displays the intersection details as well as the login ID of the current user.
Control PanelThe control panel consists of the New Tab menu (plus icon) and the Settings menu (cog icon) and can be found in the upper right-hand corner of the screen.
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Visualizing the DataTo launch the different charts, the user can open an empty tab and add the charts that they would like to monitor from the Performance Metrics menu. The tab can be saved as a template or duplicated and then modified - to leverage some of the key settings.
Settings Menu
The user can switch between day and night theme and US time zones from the Preferences pane, and they can also check the product version from the System Info pane.
Hawkeye provides advanced data visualization per lane, movement, phase, approach or per intersection. All report options are grouped into sections with expandable headings. Clicking on a heading will display the list of reports pertinent to that section.
From the Live Views contextual menu, the user can start a live streaming session from the radar.
Intersection Reports
Arrivals
Arrivals on Red
The count of vehicle arrivals at the presence zone on a red-light state. They are presented as both a numeric value and a percentage of all vehicle arrivals for the measured period. These would include:
» Vehicles on all concurrent phases on all approaches » Both right-turns and waiting-on-red cars
Chart Specifics
• X-axis – Monitored time-period • Y-axis – Primary: count of vehicles displayed on the left; Secondary:
percentage of red arrivals displayed on the right
Three metrics are plotted on a stacked area chart: arrivals on red, all arrivals and percentage rate. Each of these is represented by a graph in different color, to illustrate the relationship among them.
The monitored period is split into equal time bins, corresponding to the Time Range preferences.
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Arrivals on Green
The number of vehicle arrivals at the presence zone on a green-light state. They are presented both as an absolute count and as a percentage of all vehicle arrivals for the measured period. These would include:
» All concurrent phases on all approaches » Both right-turns and waiting-on-red cars
Chart Specifics
• X-axis – Monitored time-period• Y-axis – Primary: count of vehicles and Secondary: percentage of
green arrivals
The three metrics are plotted on a stacked area chart, each of them color-coded to illustrate the relationship among them: arrivals on red, all arrivals and percentage rate.
Use Case: Progression Through a Corridor
Without ASPM data:
• The agency would have to engage in an expensive traffic study, which is normally quite time consuming and may incur high costs.
• Alternatively, the traffic practitioner would need to start collecting TMCs at each intersection to use in a modeling software.
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With ASPM data:
• Utilize Arrivals on Red or Green to evaluate the % of vehicles that are stopping at each intersection
• Adjust the offsets to improve traffic flow and progression through a group of signals
Benefit:
• This helps save time and money.
Volume
Volume/Approach
An integral spike chart, showing the number of vehicles detected per approach over the monitored period.
Chart Specifics
• X-axis – Measured time-period• Y-axis – Count of vehicles per hour
» The measured period is split into hourly intervals » The legend provides color-coding for each lane
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Volume/Lane
Number of vehicles detected per lane over the monitored period.
Chart Specifics
• X-axis – Measured time-period • Y-axis – Count of vehicles per fifteen-minute intervals
» The user can only view one approach at a time » The color legend is segregated by approach and lane
Volume/Phase
Cumulative number of vehicles detected per phase.
Chart Specifics
• X-axis – monitored time-period • Y-axis – count of vehicles for each of the included phases
» The legend provides color-coding for each phase » Hovering over the graph will flag the number of vehicles on each individual
phase in the selected time segment. » Phases can be switched on/off to view one at a time, or as many as the user
would like to monitor.
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To get the full picture and stay on the lookout for congestion patterns, the three reports from the Volume section may be viewed in parallel.
Composition/Approach
This feature shows the number of vehicles per phase grouped by vehicle class.
Chart Specifics
• X-axis – Monitored time-period• Y-axis – Traffic composition with vehicle count per the defined classification
» The statistics covers 3 classes of traffic objects: Passenger Car, Truck, and Cycle (incl. bicycle and motorbike)
» The three graphs depict count per phase for each vehicle class
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Use Case: Vehicle Classification
Without ASPM data:
• This data can only be collected through traffic studies by companies who have the appropriate equipment and data analytics
With ASPM data:
• Truck, Car and Bike percentage can be defined
Benefit:
• Bike % can be used to determine road design for bike access• Truck % can be used for capacity design, speed limit design, passage time/
gap out settings and even EASL loading pavement designs
Delay and LOS
Delay/Vehicle/Phase
Calculates the delay for all vehicles from the moment their speed drops below 3.1 mph (5 km/h) till the moment the vehicle leaves the intersection.
Chart Specifics
• X-axis – Monitored time-period • Y-axis – Average delay in seconds
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Use Case: Long Wait Times and Delay During Off-peak Times
Without ASPM data:
• Data is incomplete - traffic studies will only capture data during peak times • Data usually covers 6 hours during the day in the AM, Midday and PM peaks• Traffic still exists outside of the peak periods and those time periods are
rarely evaluated
With ASPM data:
• Hawkeye ASPM data is 24/7/365, off-peak time period can be evaluated, and the user can quickly respond to any issues occurring
• The traffic practitioner can utilize the Delay per vehicle per phase to evaluate where excessive wait times occur
Benefit:
• Adjust minimum and maximum green settings to minimize the overall delay at the intersection
Total Delay/Vehicle/Phase
This feature provides the total delay for all vehicles on a phase, calculated as the sum of delays of all vehicles. Delay is measured as time from the moment the vehicle speed drops below 5 mph until the vehicle leaves the intersection.
Chart Specifics
• X-axis – Monitored time-period • Y-axis – Total delay in seconds (converted to minutes or hours when too long)
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Level of Service/Approach
The Level of Service feature applies a concept where the Approach is assigned a grade of assessment ranging from A to F. A represents the best quality of service, where the driver has the freedom to drive with a free-flow speed, and F represents the worst quality of motorist experience. This metric helps identify areas in need of optimization.
Speed and travel-time, density, and delay are the three parameters that affect the LOS grade assigned to each approach.
» One of the important measures of service quality is the amount of time spent in travel. Therefore, speed and travel time are considered when defining the LOS of a facility;
» Density gives the proximity of other vehicles in the stream. It affects the ability of drivers to maneuver in the traffic stream;
» Delay is a term that describes excess or unexpected time spent in travel.
Chart Specifics
• X-axis – Monitored time-period• Y-axis – Level of Service index for each respective approach
• LOS A <= 10 secs• LOS B <= 20 secs• LOS C <= 35 secs
• LOS D <= 55 secs• LOS E <= 80 secs• LOS F > 80 secs
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The default view comprises all approaches and allows an easy comparison. Zooming into a specific time segment is possible by highlighting that part of the graph
Note: To “corroborate” the findings, the LOS/Approach chart may be viewed in parallel with Volume, Occupancy% and Delay charts. This line-up provides a more holistic view on saturation patterns and helps with capacity analysis.
Level of Service/Intersection
This report visualizes the average LOS grade for the intersection overall.
It calculates as the average of all LOS/Approach grades and gives an idea of the performance of the intersection infrastructure when handling traffic. It is easy to outline trends and conclude which the most problematic intersections are. Thereon, the traffic practitioner can go deeper into researching the causes for the low performance by viewing other charts from the Hawkeye ASPM module.
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Chart Specifics
• X-axis – Monitored time-period• Y-axis – Level of Service index averaged for the intersection
Others
Average Speed
Average value of vehicles’ speed measured at Presence and Advanced zone. Whenever a measuring point is occupied by a new tracked object at a function call, its speed will be added to a variable and a counter will be incremented. When the interval time is reached, the average speed for each measuring point will be calculated.
Chart Specifics
• X-axis – Monitored time-period • Y-axis – Speed in miles per hour
» Multi-layer chart: the first layer of results visualizes when selecting a phase. Once selected, the chart refreshes and allows selection of separate lanes.
» The Presence and the Advanced zone stats can be viewed one at a time
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Presence Zone
Advanced Zone
Use Case: Capturing Vehicle Speeds
Without ASPM data:
• Traffic studies capture vehicle speeds but most likely during peak hours only.
With ASPM data:
• 24/7 speed capture is possible
Benefit:
• Data can be used for establishing the 85th percentile speed and setting speed limits.
• Speeds can also be used to establish offsets for coordinated routes
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Passed on Red
This feature provides a high-level view of the occurrence of vehicles that have left the intersection on a red-light state on each phase. The chart can be used to outline patterns with red light runners. The traffic practitioner can report those findings so that green light duration gets optimized, and potential accidents are prevented.
Chart Specifics
• X-axis – Monitored time-period• Y-axis – Count of vehicles
» For a precise figure – hover over the graph. » Phases can be switched on and off.
Occupancy %
This feature is a counter per time. It specifies the percentage of time a measuring point is occupied by a tracked object at a function call, which will get the counter to be incremented. When the interval time is reached, the occupancy will be calculated.
Chart Specifics
• X-axis – Monitored time-period • Y-axis – % of occupancy
» Multi-layer chart: the first layer divides the results by phase. Once selected, the chart will also show by-lane statistics.
» Further on, the user can select to view either Presence or Advanced zone detailed results separately.
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Presence Zone
Advanced Zone
Headway
This feature yields the average time between two vehicle’s front-to-front in seconds. Whenever the measuring point is overrun by a tracked object, a timer is started, the elapsed time will be added to a sum time and a counter will be increased. When the interval time is reached, the average Headway for each measuring point is calculated.
Formula: ℎa = 3,600/q where, q = traffic volume in veh/hour/laneha = average headway in the lane in sec
This gives Headway per hour. If the period is 15 min then ha=900/q
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Chart Specifics
• X-axis – Monitored time-period • Y-axis – Headway in seconds
Multi-layer chart – per phase and per lane:
» Phases and lanes can be switched on and off » Can only view one phase at a time
Headway spacing is selected as a criterion for assessing route capacity and safety.
• A “shorter” headway signifies closer spacing between the vehicles. Metro systems operate with headways on the order of 1 to 5 minutes, and vehicles on a freeway can have as little as 2 seconds headway between them.
• A system that requires larger headways has more empty space and thus a lower utilization. Consequently, the capacity may have potential to be improved.
Purdue Coordination Diagram
The Purdue Coordination Diagram (PCD) uses dots to depict the arrival of each vehicle during each phase and movement along each lane. Simply put, it shows the arrival of vehicles within the current light state. This comparative chart depicts vehicle arrivals in a spatial manner to allow for platoon analysis.
Chart Specifics
• X-axis – Monitored time-period• Y-axis – Total duration of cycle
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» Large clusters of dots (vehicle arrivals) within the green-shaded area illustrate good progression and platooning.
» Clusters of dots within the red area of the chart indicate the volume of vehicles arriving on red. On some occasions, excessive red area could be a normal outcome from a conflicting phase running in parallel with a green phase or can be caused by suboptimal offsets, or other intersection issues.
» The measurement point for capturing detection data can be set within the range of 10 to 100 meters (from the UMRR)
Performance
Performance Overview by Phase
This feature is a dashboard of multiple metrics, available at a glance for all phases that exist on the intersection. It is designed as an interactive heat map to highlight the hot spots that need attention.
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Report Specifics
• The data is structured in building blocks, where each cell is configurable.• Color coding highlights potential or immediate issues. • By clicking on the plus sign under Metric Data to Watch the user can add
additional parameters.
• Clicking on a cell will open a configuration box where the engineer can manually set thresholds
• Clicking on the Update cell icon (checkmark) will apply the thresholds to the specific cell only.
• Clicking on the Update row icon (chain link) will apply the settings to all the cells in the row.
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The live view is streamed directly from the Hawkeye radar. It can be switched on from the Live Views section of the Performance Metrics menu. The vehicles entering the detection field of the radar would be displayed moving along the lane they picked, with a leading yellow speed vector.
• Lane highlights - the lane under monitoring would change color to yellow once a vehicle steps on it.
• Presence/Advanced zones - for configurations distinguishing between Presence and Advances zones, the zone occupied by the vehicle would be colorized in red while it is making its passage.
• Outliers – vehicles which are moving on the side of the road or have pulled off would be captured by the radar, but the lane and zone would not change color.
Lanes can be outlined by clicking on the designated icon
The live view can be added to the dashboard of charts to complement the data collection.
Offline map can be uploaded in the event that internet connection is missing
Measurement zones can be visualized by clicking on the respective icon
Radar Live View
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Reports for Freeways
Volume/Flow
Total Volume
Direct count of vehicles per hour in dual direction, over the measured segment of the freeway.
» Vehicles on all concurrent phases on all approaches » Both right-turns and waiting-on-red cars
Chart Specifics
• X-axis – Monitored time-period• Y-axis – Total number of vehicles at the selected moment
Three metrics are plotted on a stacked area chart: arrivals on red, all arrivals and percentage rate. Each of these is represented by a graph in a different color - to illustrate the relationship among them.
The monitored period is split into equal time bins, corresponding to the Time Range preferences.
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Volume / Direction
Direct count of vehicles over hourly intervals, aggregated into a single value from the volume counts of all lanes on a given direction. Each graph on the chart depicts the fluctuations of the volume of vehicles as they occur on the respective direction.
Chart Specifics
• X-axis – Monitored time-period• Y-axis – Number of vehicles in one direction in the selected moment
Volume / Lane
Direct count of vehicle per lane, over the selected time interval. Each graph on the chart depicts the fluctuations of the volume of vehicles on the respective lane.
Chart Specifics
• X-axis – Monitored time-period• Y-axis – Number of vehicles in one direction in the selected moment
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Composition
The Hawkeye radar detects vehicle classes and feeds data, while differentiating between passenger cars, bicycles, vans, trucks etc. The statistics are collected directly from the radar as vehicle counts for the respective classes.
Chart Specifics
• X-axis – Monitored time-period• Y-axis – Number of vehicles by type
» Multi-layer chart: a direction can be switched on/off the chart » Vehicle classes can be ticked off - for focusing on specific traffic groups
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Heavy Vehicles Percentage
The ratio between heavy vehicles and the overall volume of all vehicles per direction, expressed as a percentage. An algorithm based on vehicle length is used to single out heavy vehicles, as part of the total count and other vehicle classes.
Chart Specifics
• X-axis – Monitored time-period• Y-axis – Number of vehicles by type
PHF/Lane
The peak hour factor (PHF) per lane is the hourly volume during the maximum-volume hour of the day divided by the peak 15-minute flow rate in that peak hour. The values are calculated for each individual lane.
PHF = Hourly Volume/ 4*V15max
where:
PHF = peak-hour factor,V = hourly volume (veh/h) for direction, andV15 = volume during the peak 15 min of the peak hour (veh/15 min) for direction.4 is the number of 15-minute intervals within the hour
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Chart Specifics
• X-axis – Monitored time-period• Y-axis – PHF index
The direction graphs can be viewed one at a time, with turn on/off from the radio buttons at the bottom.
Peak Hour Factor/Direction
The peak hour factor (PHF) per direction is based on the traffic in the busiest 15 minutes of the peak hour of the day. Arithmetically it calculates as the hourly volume during the maximum-volume hour of the day, divided by the peak 15-minute flow rate within that peak hour. The PHF indeces per lane are aggregated and then the calculation is averaged.
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Flow Rate/Lane
The number of passenger cars that pass over a point in a given time period, usually an hour, along a specific lane. In mathematical terms it is the result of the hourly volume per lane, divided by an argument, that takes into account PHF, multipled by the number of lanes, a heavy-vehicle adjustment factor and a driver population factor.
Chart Specifics
• X-axis – Monitored time-period• Y-axis – Number of cars per measurement interval
where:
vp = 15-min passenger-car equivalent flow rate (pc/h/direction),V = hourly volume for the direction,PHF = peak-hour factor,N = number of lanes (=1 for the direction),fHV = heavy-vehicle adjustment factor, andfp = driver population fact. We assume fp = 1.0
vp = V/ (PHF * N * fHV * fp)
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Flow Rate/Direction
The Flow Rates per Lane are averaged for the dual direction, or for as many directions as present on the monitored segment of the freeway.
Chart Specifics
• X-axis – Monitored time-period• Y-axis – Number of cars per measurement interval
Density
Density/Direction
Defined as the ratio between the Flow Rate per direction and the Time Mean Speed. Measured in vehicles/minute and calculated as follows:
Density = Flow Rate(direction)/Time Mean Speed
Chart Specifics
• X-axis – Monitored time-period• Y-axis – Density [veh/mi]
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Density/Lane
Defined as the ratio between the Flow Rate per lane and the Time Mean Speed. Measured in vehicles/minute and calculated as follows:
Density = Flow Rate(lane)/Time Mean Speed
Chart Specifics
• X-axis – Monitored time-period• Y-axis – Density [veh/mi]
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Occupancy %
Identifies the proportion of time a roadway cross section is occupied by vehicles. This metric is often used in freeway traffic demand management, to determine priority for high occupancy vehicles, in congestion pricing, and in traveler information systems.
Occupancy = (Ton / Ttotal) .100 [%]
Chart Specifics
• X-axis – Monitored time-period• Y-axis – Percentage of occupancy at the selected time
Headway
The time in seconds when a point on the freeway is overrun by two successive vehicles, front to front. A vehicle counter is started, and the measurement interval equivalent (in seconds) is divided by the average flow rate e.g., 3600s/h : 2400veh/h = 1,5 s/veh
HEADWAY = 3600 /FLOW RATE
Chart Specifics
• X-axis – Monitored time-period• Y-axis – Headway measured in seconds per vehicle
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Gap
The time in seconds when a point on the freeway is overrun by two successive vehicles. It measures the time needed to reach the rear of the first vehicle from the front bumper of the successive vehicle.
To understand the difference between headway and gap, take a look at the figure below.
Chart Specifics
• X-axis – Monitored time-period• Y-axis – the gap time, measured in seconds
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Speed
Time Mean Speed
The average of speeds of vehicles, observed passing a point on a freeway. It is a spot-based metric. The individual speeds of vehicles are recorded and averaged arithmetically.
According to HCM6, time mean speed can be measured either by referencing a point or a stretch of a distance (space) on the freeway. It is also referred to as the average spot speed. The individual speeds of vehicles passing a point are recorded and averaged arithmetically. The time mean speed is always equal to or higher than the space mean speed. The two are equal only when the speeds of all vehicles in the traffic stream are equal.
Chart Specifics
• X-axis – Monitored time-period• Y-axis – the gap time, measured in seconds
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Free Flow Speed
The average speed of vehicles on a given segment of the freeway, measured under low-volume conditions, when drivers are free to drive at their desired speed, with no constraints by the presence of other vehicles or traffic control devices (i.e., traffic signals, STOP signs).
Chart Specifics
• X-axis – Monitored time-period• Y-axis – the gap time, measured in seconds
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Speed-Volume Variation
The chart displays two graphs - the average Volume of vehicles on a direction at a given time, overlaying the graph of the Time Mean Speed. TIME MEAN SPEED is calculated in [mi/h] and VOLUME - in [veh/hours]. It shows the variation of speed and volume (and the reciprocal relationship between the two - the higher the volume, the lower the speed).
Chart Specifics
• X-axis – Monitored time-period• Y-axis – the gap time, measured in seconds
Level of Service
LOS/Direction
The Level of Service feature applies a concept for measuring the overall health of the freeway segment, based on the measured density per lane. An A-F grade is assigned to each lane, associated with a count of passenger cars per mile per lane.
Chart Specifics
• X-axis – Monitored time-period• Y-axis – the gap time, measured in seconds
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Chart Specifics
• X-axis – Monitored time-period• Y-axis – the LOS index per direction
LOS criteria for basic freeway and multilane highway segments:
• LOS A <= 11 secs• LOS B <= 11-18 secs• LOS C <= 18-26 secs
• LOS D <= 26-35 secs• LOS E <= 35-45 secs• LOS F > 34 secs
Live ViewsThe live view option allows direct video streaming from the radar through the context camera. The image is plotted on a satellite Google map and the vehicles are visualized with their leading speed vector.
• Lane highlights – as soon as a vehicle slides into the field of monitoring, the lane gets highlighted in amber;
• Zone highlights – when the vehicle enters the advanced zone, it gets highlighted in red. Same happens when the vehicle enters the presence zone – it gets red, while the advanced zone is back to amber;
• Working Offline – this option allows uploading an offline map in instances when the site does not have internet or wi-fi connection.
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Traffic Events
Traffic Interruptions
An interruption is an event registered when the individual vehicle speed drops to or below 5 mph. The event is time- and lane-stamped and listed in a table chronologically. Additional details attest to the number of affected vehicles and their speed at the drop point, plus lane localization.
Chart Specifics
• X-axis – Monitored time-period• Y-axis – the gap time, measured in seconds
Wrong Way
A list of incidents registered when a vehicle has hit a lane or an on/off-ramp exit in the wrong direction. The tabular view shows the event ID, the time it has been detected, the vehicle type and Resolved/Unresolved status of the incident. The table also registers the direction on which the even has occurred and location coordinates.
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