Choosing The Profile Type; Trapezoidal Profile Defined; Registration And Home Search Profiles Defined; Velocity Profile Defined - Automation Direct DL05 User Manual

Appendix E: High-speed Input and Pulse Output Features

Choosing the Profile Type

1
Pulse Output Mode generates three types of motion profiles. Most applications use one type
for most moves. However, each move can be different if required.
2
• Trapezoidal – Accel Slope to Target Velocity to Decel Slope
• Registration – Velocity to Position Control on Interrupt
3
• Velocity Control – Speed and Direction only

Trapezoidal Profile Defined

D
The trapezoidal profile is the most common positioning
profile. It moves the load to a pre-defined target position by
E
creating a move profile. The acceleration slope is applied at
the starting position. The deceleration slope is applied
backwards from the target position. The remainder of the
6
move in the middle is spent traveling at a defined velocity.
Trapezoidal profiles are best for simple point-to-point moves, when the distance between the
7
starting and ending positions of the move is known in advance.
Registration profiles solve a class of motion control
8
problems. In some applications, product material in work
moves past a work tool such as a drill station. Shown to the
9
right, registration marks on the scrap area of the work-piece
allow a machine tool to register its position relative to the
rectangle, to drill properly.
10
Home search moves allow open-loop motion systems to re-
calibrate (preload) the current position value at powerup.
11

Registration and Home Search Profiles Defined

Registration profiles are a combination of velocity and
1
position control modes. The move begins by accelerating to a
programmed velocity. The velocity is sustained and the move
1
is of indefinite duration. When an external interrupt signal
occurs (due to registration sensing), the profile switches from
velocity to position control. The move ends by continuing
14
motion a pre-defined distance past the interrupt point (such
as a drill hole location). The deceleration ramp is applied in
A
advance of the target position.

Velocity Profile Defined

B
The velocity profile controls only the direction and speed of
motion. There is no target position specified, so the move
C
can be of indefinite length. Only the first velocity value
needs to be defined. The remaining velocity values can be
created while motion is in progress. Arrows in the profile
D
shown indicate velocity changes.
E–30
DL05 Micro PLC User Manual, 6th Edition, Rev. A
Trapezoidal Profile
Velocity
Fixed Velocity
Accel
Start position Target position
Finished part area
direction of motion
Registration marks
Registration Profile
Velocity Position
Control Control
Velocity
Accel
Target position
Interrupt
Velocity Profile
Velocity
Decel
Time
Scrap
Area
Decel
Time