Robotis Dynamixel X Series, Manual

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DYNAMIXEL provides 3 different types of Profile. The following explains 3 Profiles.
Profiles are usually selected by the combination of
Profile Velocity(112) and Profile
Acceleration(108) .
When given Goal Position(116) , DYNAMIXEL’s profile creates desired velocity trajectory based
on present velocity(initial velocity of the Profile).
When DYNAMIXEL receives updated desired position from a new
Goal Position(116) while it is
moving toward the previous Goal Position(116) , velocity smoothly varies for the new desired
velocity trajectory.
Maintaining velocity continuity while updating desired velocity trajectory is called Velocity
Override.
For a simple calculation, let’s assume that the initial velocity of the Profile is ‘0’.
The following explains how Profile processes
Goal Position(116) instruction in Position Control
mode, Extended Position Control Mode.
1. An Instruction from the user is transmitted via DYNAMIXEL bus, then registered to Goal
Position(116) (If Velocity-based Profile is selected).
2. Acceleration time(t1) is calculated from Profile Velocity(112) and Profile Acceleration(108) .
3. Types of Profile is decided based on Profile Velocity(112) , Profile Acceleration(108) and
total travel distance(ΔPos, the distance difference between desired position and present
position).
4. Selected Profile type is stored at Moving Status(123) .
5. DYNAMIXEL is driven by the calculated desired trajectory from Profile.
6. desired velocity trajectory and desired position trajectory from Profile are stored at
Velocity
Trajectory(136) and Position Trajectory(140) respectively.
Condition Types of Profile
V
PRFL
(112) = 0
Profile not used
(Step Instruction)
(V
PRFL
(112) ≠ 0) & (A
PRF
(108) = 0) Rectangular Profile
(V
PRFL
(112) ≠ 0) & (A
PRF
(108) ≠ 0) Trapezoidal Profile