Elmo HARmonica, HARSFEN0602 132, Position reference generator, Software reference generator

ST stops any motion.

PA=n specifies a PTP motion, to the absolute position n counts JV=n specifies a Jog motion, with the speed n counts/sec

PT=n specifies a PT motion, beginning from the n’th item in the PT data table

PV=n specifies a PVT motion, beginning from the n’th item in the PVT data tables

HARSFEN0602ElmoHARmonicaSoftwareManual PRELIMINARYDRAFT

12 The position reference generator

132

The position reference signal is generated by the following components: command generator

Auxiliary command generator

•Stop manager.

This section describes the components of the position reference generator in detail.

12.1 The software reference generator

The Harmonica supports five modes of software references. The reference modes are:

Idle – The motor just stands at place. This is the default mode after setting motor on, and after an interpolated motion is complete.

PTP – Point to Point: The user specifies the position in which the motor is to stand, and the limits subject to which the trajectory to the target is to be designed. The Harmonica designs automatically a minimum-time trajectory and executes it. Jogging: The user specifies the speed in which the motor should steadily move, and the acceleration limits towards that speed. The Harmonica designs automatically a

•minimum-time trajectory and executes it.

PT – Position/Time: The user specifies a set of point to be visited with fixed time differences. The Harmonica interpolates a 3rd order polynomial between the user's points. The speeds at the user points are selected to form a smooth motion trajectory. Using the PT, complex motions are easily designed. PT data may be transferred to the amplifier on-line using an efficient CAN PDO protocol, so that infinite PT motions are possible.

PVT – Position/Velocity/Time: The user specifies a set of motion points. Each point includes a position, and the speed and the time at which the position is to be visited. The user points are interpolated using third order polynomials. The PVT mode allows absolute time specification, thus several amplifiers may compose a fully synchronized motion using the PVT mode. PVT data may be transferred to the amplifier on-line using an efficient CAN PDO protocol, so that infinite PVT motions are possible.

In order to initiate a software motion, you must initialize its parameters and issue a mode
command. The next BG (software, hardware, or timed) will start the motion.
The mode command are listed in the following table:
•
Command	Mode
ST	Idle.
PA	PTP.
JV	Jogging.
PT	PT.

PV

PVT.

Table 12-1: Software motion mode commands

12.1.1Switching Between Motion Modes

Stopping by the ST command is available anytime. The amplifier will decelerate the position reference until a complete stop.

PTP and jog motions can be commanded to anywhere, any time. The Amplifier will calculate the path to be followed so that the desired speed or position is reached, subject to the acceleration limits. PTP and jog motions can even be initiated while PT or PVT motion