SystemModelDelay
SystemModelDelay[texpr,δ]
delays the temporal expression texpr by δ units of time, i.e. texpr[t-δ].
SystemModelDelay[texpr,{δmin,δmax}]
delays texpr by a minimum delay δmin and a maximum delay δmax.
Details
- SystemModelDelay is typically used to validate requirements that have uncertain start times and may be used to consider relaxed time constraints or to quantify inertia in the system response times.
- SystemModelDelay[texpr,δ][t] is True for
if texpr[t] is True for 
. - SystemModelDelay[texpr,{δmin,δmax}][t] is True for
if texpr[t] is True for 
. - SystemModelDelay can be used to specify system behaviors in functions like SystemModelValidate.
Examples
open all close allBasic Examples (1)
Use SystemModelDelay to delay phenomena in validation:
Validate the requirement, "Whenever the controller is turned on, and for an extra period of at least 300 seconds, the room temperature must be between 19.5 °C and 20.6 °C.":
Scope (2)
Basic Uses (1)
Validate requirements in a model of a pendulum:
Validate the requirement, "Whenever the angle is non-negative, with a delay of 
seconds, the angular velocity is positive.":
Validate the requirement, "Whenever the angle is non-negative, with a delay between 
and 
seconds, the angular velocity is positive.":
Delay (1)
Validate requirements using temporal delays in a model of a pendulum:
Validate the requirement, "Whenever the angle is non-negative, with a delay of 
seconds, the angular velocity is less than or equal to 0.01.":
Use time quantities to specify delays:
Validate the requirement, "Whenever the angle is non-negative, with a delay between 
and 
seconds, the angular velocity is less than or equal to 0.":
Applications (1)
Start with a simple model of an electrical vehicle following the US EPA Highway Fuel Economy Driving Schedule (HWFET):
Validate the stricter requirement, "Whenever the velocity of the vehicle is less than or equal to 11 m/s, and for an extra period of at least 20 seconds, the temperature in the battery must remain below 28 ºC.":
Find the earliest and latest failure times:
Related Links
Wolfram System Modeler DocumentationText
Wolfram Research (2025), SystemModelDelay, Wolfram Language function, https://reference.wolfram.com/language/ref/SystemModelDelay.html.
CMS
Wolfram Language. 2025. "SystemModelDelay." Wolfram Language & System Documentation Center. Wolfram Research. https://reference.wolfram.com/language/ref/SystemModelDelay.html.
APA
Wolfram Language. (2025). SystemModelDelay. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/SystemModelDelay.html