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Figure 87:
Settings
Acceleration Type
Press the arrow by the Acceleration Type list box. It will display the various acceleration types: 5/8 S-Curve, 1/4 S-Curve,
Linear, and S-Curve.
This is used to select the acceleration/deceleration type for all motion (homes, jogs and indexes). The "S-Curve" ramps offer
the smoothest motion, but lead to higher peak acceleration/deceleration rates. "Linear" ramps have the lowest peak
acceleration/deceleration rates but they are the least smooth ramp type. "5/8 S-Curve" ramps and "1/4 S-Curve" ramps use
smoothing at the beginning and end of the ramp but have constant (linear) acceleration rates in the middle of their profiles.
The "5/8 S-Curve" is less smooth than the "S-Curve" but smoother than the "1/4 S-Curve".
S-Curve accelerations are very useful on machines where product slip is a problem. They are also useful when smooth
machine operation is critical. Linear ramps are useful in applications where low peak torque is critical. Below is a comparison
of the 4 ramp types:
S-Curve: Peak Acceleration = 2 x Average Acceleration
5/8 S-Curve: Peak Acceleration = 1.4545 x Average
1/4 S-Curve: Peak Acceleration = 1.142857 x Average Acceleration
Linear: Peak Acceleration = Average Acceleration
Honor Distance Enable
User Ramps/Auto Calculate Ramps
The user has the ability to select one of two ramp control types for the entire motion control system. By default, User Ramps is
selected. The user can change the ramp controls in PowerTools Pro and perform a download to make the change, or the
parameter AutoCalcRampsEnable can be turned On or Off within a program. To enable User Ramps, AutoCalcRampsEnable
should be turned Off, and to enable Auto Ramps, AutoCalcRampsEnable should be turned On. Once a motion profile is in
progress, changes to this parameter will be ignored until the next motion is initiated.
See the description of each of the ramp types below.
User Ramps
Prior to the introduction of this feature in firmware revision A8 of EZMotion, User Ramps was the only ramp control type
available. When User Ramps are enabled, the Acceleration or Deceleration ramp entered by the user will ALWAYS be used
during a motion profile, even if that means the motor must overshoot the entered stopping position. Under this circumstance,
the acceleration or deceleration ramp would be honored, and therefore the motor may need to reverse directions after coming
to a stop in-order to reach the user entered target position. This scenario most often occurs when using Compound or Blended
Index instructions within a program. During Compound or Blended indexes, the user occasionally does not enter an
aggressive enough acceleration or deceleration ramp to reach the target velocity within the specified distance. See the
Figures 88 and 89 below for examples of how User Ramps work. For more information on Index.#.CompoundInitiate and/or
Index.#.BlendInitiate, see the programming section of this User Guide.
Auto Calculate Ramps
When Auto Calculate Ramps is selected EZMotion will automatically calculate the necessary ramp to reach the target velocity
within the user specified distance without any overshoot. In this scenario, the user entered acceleration or deceleration rate is
ignored. See the Figures 88 and 89 below for examples of how Auto Calculate Ramps work.
EZMotion User/Programming Guide
Revision A8
Ramps View
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87
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