control.ClosedLoop Class Reference

Interface with closed loop controller. More...

Public Member Functions
def	__init__ (self, PID, satLim, setPoint)
	Constructs a closed loop controller. More...
def	update (self, Read, startTime)
	Updates the controller for timing and error between a read value and the setpoint. More...
def	get_Times (self)
	Returns time array for a step response. More...
def	getPositions (self)
	Returns motor positions array for a step response. More...
def	get_PID (self)
	Gets PID object. More...
def	set_PID (self, PID)
	Sets PID gains. More...
def	set_setPoint (self, setPoint)
	Sets or resets setpoint to a certain value.
def	sat (self, sat_duty)
	Saturation functionallity. More...

Public Attributes
	firstTime
	Instantiates PID controller with gains. More...
	i
	PID
	satLim
	Instantiates duty saturation upper and lower bounds.
	setPoint
	esum
	Sum of error over a difference in time.
	laste
	Previous error.
	times
	motorPositions

Detailed Description

Interface with closed loop controller.

Contains all methods that will be used in task_hardware to set the duty cycle based on closed loop control.

Constructor & Destructor Documentation

__init__()

def control.ClosedLoop.__init__	(		self,
			PID,
			satLim,
			setPoint
	)

Constructs a closed loop controller.

Creates variables necessary to instantiate a controller such as timing, PID gains, saturation limit, setpoint value, error, and arrays used in recording a step response

Parameters

PID	is a list containing the three gain values for Kp/Ki/Kd
satLim	is a list containing the upper and lower bounds of saturation

Member Function Documentation

get_PID()

def control.ClosedLoop.get_PID

(

self

)

Gets PID object.

Quick method to determine what controller is using for PID gains.

get_Times()

def control.ClosedLoop.get_Times

(

self

)

Returns time array for a step response.

Returns

Contains array of time over a step response

getPositions()

def control.ClosedLoop.getPositions

(

self

)

Returns motor positions array for a step response.

Returns

Contains encoder read positions of a motor over a step response

sat()

def control.ClosedLoop.sat	(		self,
			sat_duty
	)

Saturation functionallity.

Controls if a duty is too large from what is calculated in update method.

Parameters

sat_duty

is the value sent by what is calculated in update method.

Returns

Sends back either the saturated limit if duty is too high or original duty based on bounds.

set_PID()

def control.ClosedLoop.set_PID	(		self,
			PID
	)

Sets PID gains.

Sets PID gains to some new list of values for Kp/Ki/Kd

Parameters

PID	is a list containing the three gain values for Kp/Ki/Kd

update()

def control.ClosedLoop.update	(		self,
			Read,
			startTime
	)

Updates the controller for timing and error between a read value and the setpoint.

Parameters

Read	is the value returned by the sensor detecting the current state of the system (encoder position)
startTime	is the initial time for a step response.

Returns

Sends back saturated duty value using sat method.

Member Data Documentation

firstTime

control.ClosedLoop.firstTime

Instantiates PID controller with gains.

Error signal which is the difference between a reference and input (current) value.

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The documentation for this class was generated from the following file:

• PenPlotter/src/control.py