The Event_Threshold command is used to detect threshold crossings in biomechanical signals and label events accordingly. This command provides extensive control over event placement by allowing users to define frame or time offsets, include or exclude sequences, and refine detections using component selection and event constraints.

Place an event label at the frame where a signal crosses a specified value. The event is created at the frame satisfying the criteria.

This is a complicated command because there are so many options.

Event_Threshold
/RESULT_EVENT_NAME=  The name to be given to the threshold event
! /Signal_Types= The type of signal to be evaluated
! /SIGNAL_NAMES= The name of the signal to be evaluated
! /Signal_Folder= The name of the signal folder
! /SIGNAL_COMPONENTS= Use these components of the signal (May also be modified using Select_X, Select_Y, Select_Z parameters)
! /FRAME_OFFSET=  The frame offset from the threshold crossing where the event label is to be placed
! /TIME_OFFSET= The time offset from the threshold crossing where the event label is to be placed
! /EVENT_SEQUENCE= A sequence of events to perform the command within (for example: RHS+RHS)
! /EXCLUDE_EVENTS= An that falls within an EVENT_SEQUENCE event may be specified to exclude a sequence from the calculations
! /EVENT_SEQUENCE_INSTANCE= Instance of event sequence
! /EVENT_SUBSEQUENCE=A subsequence of events to perform the command within (for example: LTO+LHS)
! /SUBSEQUENCE_EXCLUDE_EVENTS=An event that falls within an EVENT_SUBSEQUENCE may be specified to exclude a subsequence from the calculations
! /EVENT_SUBSEQUENCE_INSTANCE= Instance of event subsequence
! /EVENT_INSTANCE= There may be several instances of an event crossing satisfying the criteria. 
 A value of 0 results in all crossing being assigned a label. 
 A positive number indicates the event (in sequence) to select. 
 A negative number indicates the event starting from the last event and progressing to the first event.
! /SELECT_X= (True or False)Use this component of the signal
! /SELECT_Y= (True or False)Use this component of the signal
! /SELECT_Z= (True or False)Use this component of the signal
! /SELECT_RESIDUAL= (True or False) Use this component of the signal
! /START_AT_EVENT= The search begins from the start event
! /END_AT_EVENT= The search ends at the end event
! /THRESHOLD= The value after which the event label is to be placed
! /ON_ASCENT=  (True or False) Determine the threshold when the signal is passing up through the threshold
! /ON_DESCENT= (True or False) Determine the threshold when the signal is passing down through the threshold
! /Frame_Window= The range of frames of data that must satisfy the threshold crossing. Used by the "Ensure" variable
! /ENSURE_FRAMES_BEFORE=  (True or False)Radius frames of data before crossing must lie on the same side of the threshold
! /ENSURE_FRAMES_AFTER= (True or False)Radius frames of data after crossing must lie on the same side of the threshold

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The Threshold parameter can be:

a number a PROCESSED METRIC an expression

For example:

a number
/Threshold= 1

a PROCESSED METRIC
If a METRIC value is stored in the PROCESSED folder, the Event_Threshold command will recognize and use the signal based only on the signal name.
Given a METRIC signal named THRESH stored in the PROCESSED folder, you can specify the parameter as:
/Threshold= THRESH

an expression
It is also possible to use expressions, but when using expressions you must use the full signal name.

Given a METRIC signals THRESH that is stored in a folder labeled TEST
/Threshold= METRIC::TEST::THRESH

But you can also elaborate this expression, such as
/Threshold= 1.0 + 0.2 * METRIC::TEST::THRESH

Create events using the Event_Threshold command: FP3_Y and FP3_Y_ENSURE

The event FP3_Y_ENSURE will use the Ensure Window After option on the dialog box.

Make sure to:
1) Import the SIGNAL_TYPE/FOLDER or enter these parameters manually into the text editor
2) Only one signal component may be specified at a time
3) Select label on Ascent/Descent - if neither are selected no events will be created

Event_Threshold
/RESULT_EVENT_NAME= FP3_Y
/SIGNAL_TYPES= FORCE
/SIGNAL_NAMES= FP3
! /SIGNAL_FOLDER= ORIGINAL
/SIGNAL_COMPONENTS= Y
! /FRAME_OFFSET= 0
! /TIME_OFFSET= 
! /EVENT_SEQUENCE= 
! /EXCLUDE_EVENTS= 
! /EVENT_SEQUENCE_INSTANCE= 0
! /EVENT_SUBSEQUENCE= 
! /SUBSEQUENCE_EXCLUDE_EVENTS= 
! /EVENT_SUBSEQUENCE_INSTANCE= 0
! /EVENT_INSTANCE= 0
! /SELECT_X= 
! /SELECT_Y= 
! /SELECT_Z= 
! /SELECT_RESIDUAL= 
! /START_AT_EVENT= 
! /END_AT_EVENT= 
/THRESHOLD= 0.05
/ON_ASCENT= TRUE
/ON_DESCENT= FALSE
/FRAME_WINDOW= 25
/ENSURE_FRAMES_BEFORE= FALSE
/ENSURE_FRAMES_AFTER= FALSE
;

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Event_Threshold
/RESULT_EVENT_NAME= FP3_Y_ENSURE
/SIGNAL_TYPES= FORCE
/SIGNAL_NAMES= FP3
! /SIGNAL_FOLDER= ORIGINAL
/SIGNAL_COMPONENTS= Y
! /FRAME_OFFSET= 0
! /TIME_OFFSET= 
! /EVENT_SEQUENCE= 
! /EXCLUDE_EVENTS= 
! /EVENT_SEQUENCE_INSTANCE= 0
! /EVENT_SUBSEQUENCE= 
! /SUBSEQUENCE_EXCLUDE_EVENTS= 
! /EVENT_SUBSEQUENCE_INSTANCE= 0
! /EVENT_INSTANCE= 0
! /SELECT_X= 
! /SELECT_Y= 
! /SELECT_Z= 
! /SELECT_RESIDUAL= 
! /START_AT_EVENT= 
! /END_AT_EVENT= 
/THRESHOLD= 0.05
/ON_ASCENT= TRUE
/ON_DESCENT= FALSE
/FRAME_WINDOW= 25
/ENSURE_FRAMES_BEFORE= FALSE
/ENSURE_FRAMES_AFTER= TRUE
;

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Three events should be created:

2 Instances of FP3_Y -The FP3_Y signal crosses the threshold (0.05) two times during the trial

1 Instance of FP3_Y_ENSURE -The FP3_Y signal crosses the threshold (0.05) and stays above the threshold for the frame window (25) one time during the trial | |

When defining events for subjects that use a prefix to define the data belonging to that subject, event labels will also have the prefix of the subject the events belong to.

NOTE: When using events in a command, the commands will iterate across subjects contained in the current workspace. As such, events and sequences listed as command parameters should NOT contain a prefix. As each subject is processed, the event range/sequence specified will automatically use the specific events prefixed for each subject as they are processed.