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(2) Speed entry method
Setting items: Target position [mm] , Speed [mm/s] , Acceleration [mm/s
2
] , Deceleration [mm/s
2
] ,
Load weight [g]
To obtain the total travel distance S [mm] in
absolute positioning mode, calculate the difference
between the position from where the table travel
starts to the target position. The table will move to
the Target Positionaccording to a trapezoidal
movement profile as shown in the diagram on the
right based on the set speed Vc [mm/s],
acceleration Aa [mm/s
2
] and deceleration Ad
[mm/s
2
].
In relative positioning mode the travel distance S
[mm] is equal to the Target Position.
For how to calculate the acceleration/decelaration and constant velocity times and the travel distance,
see the equations below:
Acceleration time
:
Ta = Vc / Aa [s]
Deceleration time
:
Td = Vc / Ad [s]
Acceleration distance
:
Sa = 0.5 X Aa X Ta
2
[mm]
Deceleration distance
:
Sd = 0.5 X Ad X Td
2
[mm]
Travel distance with constant velocity
:
Sc = S – Sa - Sd [mm]
Travel time with constant velocity
:
Tc = Sc / Vc [s]
Positioning time
:
Tp = Ta + Tc + Td [s]
Add settling time Ts
(
∗
)
to the total travel time Tt to get the total positioning time Tp.
(
∗
)
The settling time varies depending on the travel
distance and load weight. 0.15 seconds can be used
as a reference value.
The acceleration and deceleration should be set
lower than the maximum acceleration / deceleration
in relation to the load weight during operation as
shown in the graph on the right.
Caution
If the acceleration and deceleration is low, the table may not reach the set speed, because the
movement profile becomes triangular.
0
10,000
20,000
30,000
40,000
50,000
60,000
70,000
0
100 200 300 400 500
Load weight [g]
Max
im
u
m
acc
e
ler
a
tion
/
dec
e
ler
ation
[m
m
/s
2
]
Card motor
LAT3*-10
LAT3*-20
LAT3*-30
Td
S
peed [mm/s]
Total travel
distance S
Time [s]
Acceleration Aa
Deceleration Ad
Ta
Tc
Tp
speed Vc