SIM Trim VI

Owning Palette: Trim & Linearize VIs

Requires: Control Design and Simulation Module

Calculates the states and/or inputs of a simulation subsystem necessary to produce a set of outputs and/or state derivatives that you specify. Trimming a subsystem involves searching for a set of states and/or inputs that satisfy one or more specified output and/or state derivative conditions. Wire data to the Path input to determine the polymorphic instance to use or manually select the instance.

If the trim algorithm cannot satisfy the conditions that you specified, the algorithm returns the closest values to the conditions that you specified.

Note  You can use this VI to trim only a continuous subsystem.

Details  

SIM Trim (Path)

	Path specifies the path to the simulation subsystem on which you want to operate. You also can use the Open VI Reference Function to open a reference to a simulation subsystem and wire that reference to Path.
	States specifies the initial states of the simulation subsystem. The SIM Trim VI uses these states to begin the search for optimal trimmed values. Name specifies the name of the parameter. Parameter names of internal states are prepended with a forward slash. Input and output parameter names are not prepended with a forward slash. Value specifies the value of the parameter. Static Input? is TRUE if the parameter type is Static. The SIM Trim VI excludes static inputs and states from the search. Static Input? is FALSE if the parameter type is either Variable or Fixed. Vector? is TRUE if the parameter value is a vector or an array. Vector? is FALSE if the parameter value is a scalar. Fixed Size? is TRUE if you can replace this parameter only with a vector or an array of the same size. Fixed Size? is FALSE if you can replace this parameter with a vector or array of any size. Fixed Value? is TRUE if the parameter value is a condition that you specify for trimming a subsystem. Fixed Value? is FALSE if the parameter value is not a condition that you specify for trimming a subsystem.
	Inputs specifies the initial inputs of the simulation subsystem. The SIM Trim VI uses these inputs to begin the search for optimal trimmed values. Name specifies the name of the parameter. Value specifies the value of the parameter. Static Input? is TRUE if the parameter type is Static. The SIM Trim VI excludes static inputs and states from the search. Static Input? is FALSE if the parameter type is either Variable or Fixed. Vector? is TRUE if the parameter value is a vector or an array. Vector? is FALSE if the parameter value is a scalar. Fixed Size? is TRUE if you can replace this parameter only with a vector or an array of the same size. Fixed Size? is FALSE if you can replace this parameter with a vector or array of any size. Fixed Value? is TRUE if the parameter value is a condition that you specify for trimming a subsystem. Fixed Value? is FALSE if the parameter value is not a condition that you specify for trimming a subsystem.
	Outputs specifies the output conditions that you want to satisfy when trimming a subsystem. You specify conditions and the values of these conditions using the SIM Set Parameter Value VI. Name specifies the name of the parameter. Value specifies the value of the parameter. Static Input? is TRUE if the parameter type is Static. The SIM Trim VI excludes static inputs and states from the search. Static Input? is FALSE if the parameter type is either Variable or Fixed. Vector? is TRUE if the parameter value is a vector or an array. Vector? is FALSE if the parameter value is a scalar. Fixed Size? is TRUE if you can replace this parameter only with a vector or an array of the same size. Fixed Size? is FALSE if you can replace this parameter with a vector or array of any size. Fixed Value? is TRUE if the parameter value is a condition that you specify for trimming a subsystem. Fixed Value? is FALSE if the parameter value is not a condition that you specify for trimming a subsystem.
	State Derivatives specifies the state derivative conditions that you want to satisfy when trimming a subsystem. You specify conditions and the values of these conditions using the SIM Set Parameter Value VI. Name specifies the name of the parameter. Value specifies the value of the parameter. Static Input? is TRUE if the parameter type is Static. The SIM Trim VI excludes static inputs and states from the search. Static Input? is FALSE if the parameter type is either Variable or Fixed. Vector? is TRUE if the parameter value is a vector or an array. Vector? is FALSE if the parameter value is a scalar. Fixed Size? is TRUE if you can replace this parameter only with a vector or an array of the same size. Fixed Size? is FALSE if you can replace this parameter with a vector or array of any size. Fixed Value? is TRUE if the parameter value is a condition that you specify for trimming a subsystem. Fixed Value? is FALSE if the parameter value is not a condition that you specify for trimming a subsystem.
	error in describes error conditions that occur before this node runs. This input provides standard error in functionality.
	Trimmed States returns the state values necessary to satisfy any conditions that you specified. Name returns the name of the parameter. Value returns the value of the parameter. Static Input? returns TRUE if the parameter type Static. The SIM Trim VI excludes Static inputs and outputs from the search. Static Input? returns FALSE if the parameter type is either Variable or Fixed. Vector? returns TRUE if the parameter value is a vector or an array. Vector? returns FALSE if the parameter value is a scalar. Fixed Size? returns TRUE if you can replace this parameter only with a vector or an array of the same size. Fixed Size? returns FALSE if you can replace this parameter with a vector or array of any size. Fixed Value? returns TRUE if the parameter value is a condition that you specify for trimming a subsystem. Fixed Value? returns FALSE if the parameter value is not a condition that you specify for trimming a subsystem.
	Trimmed Inputs returns the input values necessary to satisfy any conditions you specified. Name returns the name of the parameter. Value returns the value of the parameter. Static Input? returns TRUE if the parameter type Static. The SIM Trim VI excludes Static inputs and outputs from the search. Static Input? returns FALSE if the parameter type is either Variable or Fixed. Vector? returns TRUE if the parameter value is a vector or an array. Vector? returns FALSE if the parameter value is a scalar. Fixed Size? returns TRUE if you can replace this parameter only with a vector or an array of the same size. Fixed Size? returns FALSE if you can replace this parameter with a vector or array of any size. Fixed Value? returns TRUE if the parameter value is a condition that you specify for trimming a subsystem. Fixed Value? returns FALSE if the parameter value is not a condition that you specify for trimming a subsystem.
	Trimmed Outputs returns the output values that occur when you apply the Trimmed States and Trimmed Inputs parameters to the subsystem. Name returns the name of the parameter. Value returns the value of the parameter. Static Input? returns TRUE if the parameter type Static. The SIM Trim VI excludes Static inputs and outputs from the search. Static Input? returns FALSE if the parameter type is either Variable or Fixed. Vector? returns TRUE if the parameter value is a vector or an array. Vector? returns FALSE if the parameter value is a scalar. Fixed Size? returns TRUE if you can replace this parameter only with a vector or an array of the same size. Fixed Size? returns FALSE if you can replace this parameter with a vector or array of any size. Fixed Value? returns TRUE if the parameter value is a condition that you specify for trimming a subsystem. Fixed Value? returns FALSE if the parameter value is not a condition that you specify for trimming a subsystem.
	Trimmed State Derivatives returns the state derivative values that occur when you apply the Trimmed States and Trimmed Inputs parameters to the subsystem. Name returns the name of the parameter. Value returns the value of the parameter. Static Input? returns TRUE if the parameter type Static. The SIM Trim VI excludes Static inputs and outputs from the search. Static Input? returns FALSE if the parameter type is either Variable or Fixed. Vector? returns TRUE if the parameter value is a vector or an array. Vector? returns FALSE if the parameter value is a scalar. Fixed Size? returns TRUE if you can replace this parameter only with a vector or an array of the same size. Fixed Size? returns FALSE if you can replace this parameter with a vector or array of any size. Fixed Value? returns TRUE if the parameter value is a condition that you specify for trimming a subsystem. Fixed Value? returns FALSE if the parameter value is not a condition that you specify for trimming a subsystem.
	error out contains error information. This output provides standard error out functionality.

SIM Trim (Reference)

	Reference specifies a reference to the subsystem on which you want to operate.
	States specifies the initial states of the simulation subsystem. The SIM Trim VI uses these states to begin the search for optimal trimmed values. Name specifies the name of the parameter. Parameter names of internal states are prepended with a forward slash. Input and output parameter names are not prepended with a forward slash. Value specifies the value of the parameter. Static Input? is TRUE if the parameter type is Static. The SIM Trim VI excludes static inputs and states from the search. Static Input? is FALSE if the parameter type is either Variable or Fixed. Vector? is TRUE if the parameter value is a vector or an array. Vector? is FALSE if the parameter value is a scalar. Fixed Size? is TRUE if you can replace this parameter only with a vector or an array of the same size. Fixed Size? is FALSE if you can replace this parameter with a vector or array of any size. Fixed Value? is TRUE if the parameter value is a condition that you specify for trimming a subsystem. Fixed Value? is FALSE if the parameter value is not a condition that you specify for trimming a subsystem.
	Inputs specifies the initial inputs of the simulation subsystem. The SIM Trim VI uses these inputs to begin the search for optimal trimmed values. Name specifies the name of the parameter. Value specifies the value of the parameter. Static Input? is TRUE if the parameter type is Static. The SIM Trim VI excludes static inputs and states from the search. Static Input? is FALSE if the parameter type is either Variable or Fixed. Vector? is TRUE if the parameter value is a vector or an array. Vector? is FALSE if the parameter value is a scalar. Fixed Size? is TRUE if you can replace this parameter only with a vector or an array of the same size. Fixed Size? is FALSE if you can replace this parameter with a vector or array of any size. Fixed Value? is TRUE if the parameter value is a condition that you specify for trimming a subsystem. Fixed Value? is FALSE if the parameter value is not a condition that you specify for trimming a subsystem.
	Outputs specifies the output conditions that you want to satisfy when trimming a subsystem. You specify conditions and the values of these conditions using the SIM Set Parameter Value VI. Name specifies the name of the parameter. Value specifies the value of the parameter. Static Input? is TRUE if the parameter type is Static. The SIM Trim VI excludes static inputs and states from the search. Static Input? is FALSE if the parameter type is either Variable or Fixed. Vector? is TRUE if the parameter value is a vector or an array. Vector? is FALSE if the parameter value is a scalar. Fixed Size? is TRUE if you can replace this parameter only with a vector or an array of the same size. Fixed Size? is FALSE if you can replace this parameter with a vector or array of any size. Fixed Value? is TRUE if the parameter value is a condition that you specify for trimming a subsystem. Fixed Value? is FALSE if the parameter value is not a condition that you specify for trimming a subsystem.
	State Derivatives specifies the state derivative conditions that you want to satisfy when trimming a subsystem. You specify conditions and the values of these conditions using the SIM Set Parameter Value VI. Name specifies the name of the parameter. Value specifies the value of the parameter. Static Input? is TRUE if the parameter type is Static. The SIM Trim VI excludes static inputs and states from the search. Static Input? is FALSE if the parameter type is either Variable or Fixed. Vector? is TRUE if the parameter value is a vector or an array. Vector? is FALSE if the parameter value is a scalar. Fixed Size? is TRUE if you can replace this parameter only with a vector or an array of the same size. Fixed Size? is FALSE if you can replace this parameter with a vector or array of any size. Fixed Value? is TRUE if the parameter value is a condition that you specify for trimming a subsystem. Fixed Value? is FALSE if the parameter value is not a condition that you specify for trimming a subsystem.
	error in describes error conditions that occur before this node runs. This input provides standard error in functionality.
	Trimmed States returns the state values necessary to satisfy any conditions that you specified. Name returns the name of the parameter. Value returns the value of the parameter. Static Input? returns TRUE if the parameter type Static. The SIM Trim VI excludes Static inputs and outputs from the search. Static Input? returns FALSE if the parameter type is either Variable or Fixed. Vector? returns TRUE if the parameter value is a vector or an array. Vector? returns FALSE if the parameter value is a scalar. Fixed Size? returns TRUE if you can replace this parameter only with a vector or an array of the same size. Fixed Size? returns FALSE if you can replace this parameter with a vector or array of any size. Fixed Value? returns TRUE if the parameter value is a condition that you specify for trimming a subsystem. Fixed Value? returns FALSE if the parameter value is not a condition that you specify for trimming a subsystem.
	Trimmed Inputs returns the input values necessary to satisfy any conditions you specified. Name returns the name of the parameter. Value returns the value of the parameter. Static Input? returns TRUE if the parameter type Static. The SIM Trim VI excludes Static inputs and outputs from the search. Static Input? returns FALSE if the parameter type is either Variable or Fixed. Vector? returns TRUE if the parameter value is a vector or an array. Vector? returns FALSE if the parameter value is a scalar. Fixed Size? returns TRUE if you can replace this parameter only with a vector or an array of the same size. Fixed Size? returns FALSE if you can replace this parameter with a vector or array of any size. Fixed Value? returns TRUE if the parameter value is a condition that you specify for trimming a subsystem. Fixed Value? returns FALSE if the parameter value is not a condition that you specify for trimming a subsystem.
	Trimmed Outputs returns the output values that occur when you apply the Trimmed States and Trimmed Inputs parameters to the subsystem. Name returns the name of the parameter. Value returns the value of the parameter. Static Input? returns TRUE if the parameter type Static. The SIM Trim VI excludes Static inputs and outputs from the search. Static Input? returns FALSE if the parameter type is either Variable or Fixed. Vector? returns TRUE if the parameter value is a vector or an array. Vector? returns FALSE if the parameter value is a scalar. Fixed Size? returns TRUE if you can replace this parameter only with a vector or an array of the same size. Fixed Size? returns FALSE if you can replace this parameter with a vector or array of any size. Fixed Value? returns TRUE if the parameter value is a condition that you specify for trimming a subsystem. Fixed Value? returns FALSE if the parameter value is not a condition that you specify for trimming a subsystem.
	Trimmed State Derivatives returns the state derivative values that occur when you apply the Trimmed States and Trimmed Inputs parameters to the subsystem. Name returns the name of the parameter. Value returns the value of the parameter. Static Input? returns TRUE if the parameter type Static. The SIM Trim VI excludes Static inputs and outputs from the search. Static Input? returns FALSE if the parameter type is either Variable or Fixed. Vector? returns TRUE if the parameter value is a vector or an array. Vector? returns FALSE if the parameter value is a scalar. Fixed Size? returns TRUE if you can replace this parameter only with a vector or an array of the same size. Fixed Size? returns FALSE if you can replace this parameter with a vector or array of any size. Fixed Value? returns TRUE if the parameter value is a condition that you specify for trimming a subsystem. Fixed Value? returns FALSE if the parameter value is not a condition that you specify for trimming a subsystem.
	error out contains error information. This output provides standard error out functionality.

SIM Trim Details

You specify the inputs to this VI as a set of State Derivatives dx₀ and an initial search point that consists of Inputs u₀, States x₀, and Outputs y₀. This VI varies the values of the initial search point to minimize the maximum value resulting from the absolute value of (u–u₀), (x–x₀), and (y–y₀), such that the absolute value of (dx–dx₀) equals 0.

This VI then returns the result of this search as a set of Trimmed States, Trimmed Inputs, Trimmed Outputs, and Trimmed State Derivatives that approximates the optimal solution. If this VI cannot find a point such that the absolute value of (dx–dx₀) = 0, this VI returns a point where the absolute value of (dx–dx₀) is as small as possible.