Operation Theorem
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4.10 Trapezoidal Motion
This mode is used to move one or more axes to a specified position (or
distance) with a trapezoidal velocity profile. Single axis and multi -axes are
controlled from point to point or follow a specific path like ARC. An absolute or
relative motion can be performed. In absolute mode, the target position is
assigned. In relative mode, the target displacement is assigned. In both
absolute and relative mode, the acceleration and the deceleration time in
seconds can be different. The
_8136_motion_status()
function is used to
check whether the movement is complete( the pulse command is all sent).
The following diagram shows the trapezoidal profile. The target position or
distance must b e given in the unit of pulse.
The physical length or angle of one movement is dependent on the motor
driver and the mechanism (includes the motor). Since absolute move mode
needs the information of current actual position, so “External encoder
feedback (EA, EB pins)” must be connected or the feedback source must be
assigned in
_8136_M_set_Feedback()
function if you don't have encoder on
axis0 to 2. You can assign the feedback source to be the command pulses
only if you are using axis0 to 2. Otherwise, you must connect a encoder
feedback signal on that axis. An example for PTP motion function is as
follows:
_8136_Start_TR_Move(CardNo, Distance, str_vel, max_vel, Tacc,
Tdec)
There are some similar parameters in all motion functions. The str_vel and
max_vel parameters are given in the unit of pulse per second (pps). The Tacc
and Tdec parameters are given in the unit of seconds. They represent
accel./decel time respectively. You have to know the physical meaning of
“one movement” to calculate the physical value of the relative velocity or
acceleration parameters. The following formula gives the basic relationship
between these parameters.
max_vel = s accel*Tacc;
0=decel*Tdec
where accel/decel represents the acceleration/deceleration rate in unit of
pps/sec. The area inside the trapezoidal profile represents the moving
distance.
Summary of Contents for PCI-8136M
Page 1: ...PCI 8136M 6 Axis Motion Controller Card User s Guide ...
Page 2: ......
