MC-Basic:axis.PositionBacklash

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Adds a position backlash value to the pcmd value. The value will be added in positive direction of the movement (<axis>.vcmd > 0) while in opposite direction the value multiplied by -1 will be used. In stand-still situation (vcmd = 0) the previous value of the backlash is used.

Changes between positive and negative applied backlash value will be smoothen by a simple alpha-filter : Axystems:MC-Basic:axis.PositionBacklashAlpha.

According to:

P = P*Alpha + sign*PositionBacklash*(1-Alpha)

where sign = -1 on vcmd <0 else equals 1.

IMPORTANT.svgIMPORTANT
The backlash position value is not compensated in the position feedback. Therefore applying position backlash to a certain non-zero value will result in having the same opposite value in PE (position error) it will look like PE is never closed.


WARNING.svgWARNING
Be cautious. The feature is not tested well enough.

Short form

None

Syntax

<axis>.PositionBacklash = double

Availability

4.5.33 and later

Type

double

Range

MIND ... MAXD

Units

position user units

Default

0

Scope

Task, Terminal

Limitations

Modal-Only

Examples

a1.PositionBacklash = 0.5

See Also