Closed-Loop Parameters

Closed-loop parameters are parameters related to the Closed-Loop function. These parameters are set using functions such as SetParam and SetClosedLoopParam.

The closed-loop parameters consist of PID parameters and sensor parameters.

PID Parameters

PidParam is part of the closed-loop parameters regarding the PID controller.

PidParam consists of the following parameters:

• Proportional Gain Kp

• Integral Gain Ki

• Derivative Gain Kd

• Derivative Filter Time Constant

• Limit Integral

• Limit Output

• Deadband

• Control Output Offset

Please refer to PID Parameter for detailed information.

Proportional Gain Kp
Variable Name:	proportionalGain
Type:	double
Default Value:	0

This parameter determines the proportional gain of the PID controller.

Integral Gain Ki
Variable Name:	integralGain
Type:	double
Default Value:	0

This parameter determines the integral gain of the PID controller.

Derivative Gain Kd
Variable Name:	derivativeGain
Type:	double
Default Value:	0

This parameter determines the derivative gain of the PID controller.

Derivative Filter Time Constant
Variable Name:	derivativeFilterTimeConstant
Type:	double
Unit:	second
Minimum Value:	0
Default Value:	0

This parameter determines the time constant of the derivative filter for the PID controller. The derivative filter is a first-order Low Pass Filter (LPF).

Proper selection of the time constant is crucial. It should account for the frequency characteristics of the sensor noise, along with the Nyquist frequency which depends on the sampling period (or the communication cycle time).

If set to 0, the derivative filter is disabled.

Integrator Saturation Limit
Variable Name:	limitIntegral
Type:	double
Minimum Value:	0
Default Value:	0

This parameter determines the saturation absolute limit of the integral term for the PID controller.

If set to 0, the saturation action is disabled. Otherwise, it should be set to a positive value. In this case, the integral term whose absolute value is greater than or equal to this parameter will be saturated, preventing the integral windup problem.

Controller Output Saturation Limit
Variable Name:	limitOutput
Type:	double
Minimum Value:	0
Default Value:	0

This parameter determines the saturation limit of the PID controller output.

If set to 0, the saturation action is disabled. Otherwise, it should be set to a positive value. In this case, the PID output whose absolute value is greater than or equal to this parameter will be saturated, preventing the controller output to exceed the physical or safety limit.

Controller Input Deadband
Variable Name:	deadband
Type:	double
Minimum Value:	0
Default Value:	0

This parameter determines the deadband limit of the PID controller’s input error signal.

If set to 0, the deadband action is disabled. Otherwise, it should be set to a positive value. Please also see “Deadband” section in PID Parameter

Controller Output Offset
Variable Name:	controlOutputOffset
Type:	double
Default Value:	0

This parameter determines the offset added to the PID controller’s output signal.

Sensor Parameters

SensorParam is part of the closed-loop parameters regarding the feedback sensor.

SensorParam consists of the following parameters:

• Sensor Type

• Feedback Data

• Sensor Minimum

• Sensor Maximum

• Sensor Offset

Please refer to Sensor Parameter for detailed information.

Sensor Type
Variable Name:	sensorType
Type:	SensorType
Default Value:	None

This parameter determines the sensor type of the feedback data. Depending on this value, either sensor feedback is disabled, AnalogData is used, or AxisData is used.

Feedback Data

Feedback is part of the sensor parameters regarding the feedback data. Depending on the value of the sensorType, different kind of feedback parameter will be used.

AnalogData consists of the following parameters:

• Byte Address

• Type

• Minimum

• Maximum

AxisData consists of the following parameters:

• Axis

• Type

Please refer to Sensor Parameter for detailed information.

Analog Input Byte Address
Variable Name:	byteAddress
Type:	int
Minimum Value:	0
Maximum Value:	maxIoInSize - 1
Default Value:	0

This parameter determines the analog input start byte address of the I/O module.

Analog Data Type
Variable Name:	type
Type:	AnalogDataType
Default Value:	None

This parameter determines the analog data size to read from the start byte address of the I/O module. For example, if the data type is specified as Int, the analog input value will read 4 bytes starting from byteAddress as signed integer.

Analog Data Minimum
Variable Name:	minimum
Type:	int
Default Value:	0

This parameter determines the minimum value of the analog data.

Analog Data Maximum
Variable Name:	maximum
Type:	int
Default Value:	0

This parameter determines the maximum value of the analog data.

Axis
Variable Name:	axis
Type:	int
Minimum Value:	0
Maximum Value:	maxAxes - 1
Default Value:	0

This parameter determines the axis of the feedback data to be used.

Axis Data Type
Variable Name:	type
Type:	AxisDataType
Default Value:	None

This parameter determines the axis data type to read from the feedback data of the axis specified by axis.

Sensor Minimum
Variable Name:	minimum
Type:	double
Default Value:	0

This parameter determines the minimum value of the feedabck sensor.

Sensor Maximum
Variable Name:	maximum
Type:	double
Default Value:	0

This parameter determines the maximum value of the feedback sensor.

Sensor Offset
Variable Name:	offset
Type:	double
Default Value:	0

This parameter determines the offset added to the feedback sensor.