Timed ramps and dwells - a FUNCTION example

Timed ramps and dwells - a FUNCTION example

Functions to make timed position ramps and dwells. For example as might be used in a blow moulding controller.

' Function library to support timed ramps
'
'Declare a universal value to hold the table index
DIM tab_index AS INTEGER

' Set up a linear TABLE
FUNCTION set_tab(index AS INTEGER, local_units AS FLOAT)
     DIM i, c AS INTEGER
     c = 0
     FOR i = index TO index + 10
          TABLE(i, c * local_units / 10)
          c = c + 1
     NEXT i
     tab_index = index
ENDFUNC

FUNCTION print_index()
     PRINT #0, tab_index
ENDFUNC

FUNCTION move_time(target_dist, ramp_time AS FLOAT)
     SPEED = 100 / ramp_time
     ACC(SPEED * 1000)
     CAM(tab_index, tab_index + 10, target_dist, 100)
ENDFUNC

FUNCTION dwell(d_time AS FLOAT)
     WA(d_time * 1000000 / SERVO_PERIOD)
ENDFUNC

Example program:

' For blow moulding applications, a sequnce is needed that ramps up an axis over a period of time
' then applies a delay before doing another ramp at a different set rate.
' The sequence is as follows:
' move_time(target_position1, ramp_time1)
' dwell(dwell_time1)
' move_time(target_position2, ramp_time2)
' dwell(dwell_time2)
' move_time(target_position3, ramp_time3)
' dwell(dwell_time3)

' The TrioBASIC command that fits a change in position over a set time is CAM.
' With a linear ramp in the TABLE, it will represent a move over time.

' setup the axis
BASE(10)
UNITS = 50
SERVO = ON
WDOG = ON
DEFPOS(0)

set_tab(100, UNITS)

TRIGGER ' start the scope

move_time(100, 2.5)
WAIT IDLE
dwell(1)
move_time(50, 3.25)
WAIT IDLE
dwell(1.5)
move_time(50, 2.0)
WAIT IDLE
dwell(1.5)
move_time(-200, 5.0)
WAIT IDLE



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