Rule Checks

Owned by Charlotte Dakin-Norris, created
Last updated: Feb 12, 2024
9 min read

Introduction

Checks, and Links (which also perform checks), verify if a rule has been broken subject to specified conditions.

Contents

Checks

Approach Check

Checks if the track sighting is approaching an Area.

Area: Specify the Area from a list of existing Areas.

Check: Specify whether the rule is broken when it is greater than or less than the value.

Max Distance: A target is not allowed within the specified distance of the Area.

Max Time: A target is not allowed within the specified time of the Area base on the targets approach speed.

Area Check

Checks if the track sighting has entered an Area.

Check Time: The time the check is performed.

Now: The current track being evaluated is in the area at this moment in time.

Anytime: The check will evaluate to true if the track has been in that area at any time. This enables us to look historically where a track has been. For example, if you wanted a rule break when a track has moved through area A into area B, then area A would be an anytime check and area B would be a now check. You would use a Boolean Link specified AND to link these Area Check nodes together in the rule logic.

Area: Specify the Area from a list of existing Areas.

Area Exclusion Check

Checks if a track has not entered one or more alarm areas.

Selected/Name: Select the alarm areas that will not be checked for track sightings.

ATI Check

Checks if the track sighting has originated from an area.

Area: Specify the Area from a list of existing Areas.

Breach Line Check

Checks if a Track Sighting has crossed a defined line.

Breach Line: Select from a list of existing Breach Lines.

Min Seen: Minimum number of track sightings required to confirm that the line is breached.

Reset Time: Length of time(s) allowed between track sightings before Seen value is reset.

Break Allowance: The number of times a single track can be seen breaching the line before alarmig.

Breach Line Proximity Check

Checks if an unknown Track Sighting is within a defined distance of an IFF track and a specified classification and is within a certain defined distance of a selected breach line it would be marked as a friend.

Breach Line: Select from a list of existing Breach Lines.

Classification for IFF Track: Select the desired object from the drop-down list.

Classification Check

Checks if the Track Sighting has been classified against a particular model.

Classification: Select the desired classification model(s).

Probability: The probability above which the track sighting has to be.

Count Check

Checks if the required number of Track Sightings have occurred within a given time period.

Area: Specify the Area from a list of existing Areas.

Count: The minimum number of track sightings required within the time period.

Time Frame: Specify the length of the given time period in seconds.

Density Check

Checks if an Area has the required density of Track Sightings within a given time period.

Area: Specify the Area from a list of existing Areas.

Density: The minimum and maximum number of tracks in the Area, in the Time Frame, required to satisfy the Density Check.

Time Frame: Specify the given time period in seconds.

External Trigger

Checks an external sensor input with debounce.

Debounce Period: Ensures that only one digital signal can be registered within this given time.

Filtered Property Check

Check if a property of a Track Sighting meets the defined criteria after previous rule checks have passed.

Property Name: Name of property to check on a track sighting.

Property Test: Select the type of test to perform on the property.

Property Check

Check if a property of a Track Sighting meets the defined criteria.

Property Name: Name of property to check on a track sighting.

Property Test: Select the type of test to perform on the property.

Proximity Check

Check if the Track Sight is within the given proximity of other sightings.

Use Time: Select between Time or Distance.

Proximity Time: Specify the number of seconds between tracks.

Proximity Distance: Specify the maximum distance (m) between tracks that satisfies the Proximity Check and triggers an action i.e., the ≤ distance between tracks at which they are considered in proximity to one another.

Area: Specify the Area from a list of existing Areas.

Classification: Select the desired classification for the track in proximity. The current track being assessed will only be checked for proximity to another track of the selected classification type. Do not select any types if you want the proximity check to ignore classifications.

Probability: The classification probability above which the track must be to be considered for the proximity check. This allows you to set a confidence level associated with the classification.

Radar Check

Check if the Track Sighting was generated by the specified radar.

Rule Broken Check

Checks if the Track has broken any of the selected rules.

Selected/Name: Select the rule(s) that will checked to see if a track sighting has broken them.

Rule Disarm Check

Checks an external trigger to disarm the rule.

Trigger Id: The Id of the external trigger's input.

Disarm Timeout (s): The time period, without an external trigger, after a rule has been disarmed before the rule is armed again.

Debounce Period (s): Ensures that only one digital signal can be registered within this given time.

Schedule Check

Checks if the track sighting recorded time or time input occurred within the given schedule.

Schedule: One or more schedules to check.

Static Sensor

Checks if the track sighting was generated by the specified sensor.

Debounce Period (s): Ensures that only one digital signal can be registered within this given time.

Static Sensor: Specify the sensor from a list of existing static sensors.

Allow Notifications: When ticked will cause static sensor to animate in UI when triggered.

System Mode

Checks the current system mode.

System Mode: Select the desired mode.

Track Tag Property Check

Will return true if any track’s tag is equal to any added tag target name.

Tag Name: Add a Tag Name to the Tag Target Names list.

Verify with ML

Verify the classification using ML object detection.

Classification: Select the classification type or types.

Probability (%): This is the minimum level of confidence required before you consider the track to have been successfully classified.

Frames to Check: The number of camera frames to check before a target can be classified.

Positive Frames: The number of positive sightings within the specified number of Frames to Check before a target can be classified.

Continual Analysis: Select if you want the system to continue the classification process after the initial classification has been completed.

Enable Secondary: Select this option to enable a secondary classification verification.

The secondary classification has to appear inside or near to the first classification. For example, if a car and it's numberplate were detected, then the primary classification would be the car, and secondary would be the numberplate. The system works out that the two are related because the smaller object (numberplate) is within or very close to the car.

Checks multiple inputs using the specified logic type. In most computer programming languages, a Boolean data type is a data type with only two possible values: true or false. The values we use are Both, Either or None.

And/Or: A boolean AND or boolean OR operation.

Not: A boolean NOT operator.

Break Count Check

Checks if the total break count for inputs has exceeded an amount.

A Gate Link will delay the output of a high state (true) for the specified time period when it receives a high input from the preceding check. The timer only starts once the Gate Link receives a high input. If the Gate Link receives a low input before the timer has expired then the timer is disabled until the next high input upon which the timer will restart. The check can apply to individual tracks or it can operate globally and look at more than one track but the principal still applies, there must be a continuous high input from one or more tracks for the duration of the configured time frame.

Time Frame (s): The length of the delay in seconds.

Gate Link requires two inputs. Related information on the inputs can be found here:

The Gate Link is global and therefore will reset if any track input produces a low input (false).

A Time Link will hold the output high (true) for the specified time period when it receives a high input from the preceding check. This means that the timer starts or is reset from whenever the last preceding check evaluated to true. This check applies to all tracks so any track can initiate the timer and any subsequent track can keep the timer running.

Time Frame (s): Specify the time frame in which the check must be satisfied.

Time link requires two inputs. Related information on the inputs can be found here:

The Time Link is track based so will maintain state if at least one track is providing a high input to the link.

Safety is everything.