BA II Arm Robot Catalog - TM Robotics - #244

How to Calculate Tact (Cycle) Time

The tact time (cycle time) of a single robot can be figured out from the following calculations. It provides only a yardstick, however, because the time thus calculated differs more or less from actual time.

The calculation comes in the two methods; Example calculation 1 (when equi-speed interval is included) and Example calculation 2 (when an axis starts decelerating during acceleration). Either calculation method is selectable according to the relationship between travel distance, specified speed and specified acceleration/deceleration time.

[1] When "travel distance > specified speed (V) * specified acceleration/deceleration time (ACC)" == Example calculation 1 [2] When "travel distance < specified speed (V) * specified acceleration/deceleration time (ACC) == Example calculation 2

For the acceleration/deceleration time, refer to the relationship between acceleration/deceleration and load as shown in the next page. For the acceleration/deceleration time and maximum speed under maximum payload, refer to the specifications of each axis type.

Example calculation 1

La = Travel distance at acceleration (mm) Lb = Travel distance at equi-speed Lc = Travel distance at deceleration (mm) Lt = Equi-speed time (s) L = Travel distance (mm) = La + Lb + Lc V = Specified speed (mm/s) t = Time (s)

Acc = Specified acceleration/deceleration time (s)

V

-2-xVxAcc = ;2-><i000*0.3 = 150mm

La : Lc :

<Operating conditions>

Specified speed : V = 1,000 mm/s

Specified acceleration/deceleration time : ACC = 0.3 s

Travel distance: L = 400 mm

xVxAcc ^:

*1000*0.3 = 150mm

. _t = L-(La + Lc) = 400-(150 + 150) =_{0 1} ^Lt V 1000 ^0is

Tact time = Acceleration time + Equi-speed time + Deceleration time = 0.3 + 0.1 + 0.3 = 0.7 sec

Example calculation 2

V = Specified speed (mm/s)

Vm = Real maximum speed (mm/s)

L = Travel distance (mm)

La = Travel distance at acceleration (mm)

Lc = Travel distance at deceleration (mm)

Acc = Specified acceleration/deceleration time (s)

t = Time (s)

o

ss

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O O

o

CD

a o

CD =1

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CD

■ L 200

La = 2 = ~2~ = 100mm

■ L 200

Lc = 2 = ~2~ = 100mm

LxACC = 21 200x0.3

Tact time = 2

<Operating conditions>

Specified speed : V = 1,000 mm/s

Specified acceleration/deceleration time : ACC = 0.3 s

Travel distance: L = 200 mm

V ^ 1000 = 0.49 sec

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