HEIDENHAIN TNC 426 PB - Minimum Distance

6 – 112 HEIDENHAIN Technical Manual TNC 426, TNC 430
Minimum distance To attain the maximum velocity, a minimum distance s
min
must be traversed.
If the traversed distance is greater than s
min
, a movement with constant
speed is inserted at the time 2T
r
. The minimum distance is:
Example Rapid traverse v
max
= 30 000 mm/min (= 0.5 m/s); MP1010.x = 30000
Max. jerk with velocity v > 20 000 mm/min (= 0.33 m/s) r
max1
=70m/s
3
;
MP1090.1 = 70, MP1092 = 20000
Max. jerk r
max2
= 35 m/s
3
during machining; MP1090.0 = 35
Maximum attainable acceleration a
max1
during rapid traverse:
Maximum attainable acceleration a
max2
during machining (v up to
20 000 mm/min):
Distance s
min
required to attain rapid-traverse velocity:
s
min
2v
max
v
max
r
max
------------⋅⋅=
Distance s
Acceleration a
t
T
r
2T
r
3T
r
4T
r
Jerk r
Velocity v
s
min
v
max
a
max1
v
max
r
max1
⋅ 0.5
m
s
------ 7 0
m
s
3
------⋅ 5.92
m
s
2
------== =
a
max2
v
max
r
max2
⋅ 0.33
m
s
------ 3 5
m
s
3
------⋅ 3.40
m
s
2
------== =
s
min
2v
max
v
max
r
max
------------⋅⋅ 20.5
m
s
------
0.5
m
s
------
70
m
s
3
-------
---------------⋅⋅ 0.085 m 85 mm== ==
Note
The rectangular jerk curve is rounded through the use of a nominal position
value filter (MP1096 ≠ 0). As a result, acceleration is reduced and the
minimum distance required for attaining the maximum velocity is
increased.