Ramp
A Ramp function () is a linear increase with a user-defined slope that begins at some specified time. The ramp function is a function of one variable (the time t, for example). The default Function name is rm1.
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See Function Names and Calling Functions for information about the Function name section.
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See Common Settings for the Function Nodes for information about the Smoothing section.
Parameters
Enter a Location value s0 for the start of the ramp. The function evaluates to a baseline value for values less than its start location and increases linearly for values greater than the location.
If the Smooth at start check box is selected under Smoothing, then the Ramp function can become nonzero at some time before the location value. A model might not solve due to the possible inconsistencies between the ramp excitation and the initial condition (for example, the initial condition is zero, but the ramp function returns a small nonzero value at the start time for the simulation).
Enter a Slope k (dimensionless) of the ramp. The default is 1.
To ensure that the value never exceeds a certain point, select the Cutoff check box and enter a value in the associated text field. The default is 1.
You can also enter a Baseline (default: 0).
For an input variable s, a start location s0, a slope k, and a baseline f0, the ramp function’s value is f0 for s < s0 and k(s−s0)+f0 for s ≥ s0 (until the cutoff value is reached, if using). You can use unit syntax to assign units to these parameters.