Operation
Theory of Operation
318 MagneMotion
Rockwell Automation Publication MMI-UM002F-EN-P - October 2022
vehicle edge location relative to the block boundary. The anti-collision feature in the Magne-
Mover LITE motor software keeps two vehicles from occupying the same motor block.
Motor Operation
The MagneMover LITE motors provide asynchronous control of vehicles (pucks) on the
transport system as directed by the host controller. This control method minimizes the load on
the host controller with the node controllers and motors performing all routing and vehicle
control operations (positioning, acceleration, deceleration, and collision avoidance) as
described in the following sequence.
1. The host controller generates an asynchronous motion order to move a vehicle to a
specific location and sends it to the high-level controller (HLC) using either a position
or station command. Locations are always defined from the beginning of a path.
For example, the Order is to move Vehicle #1 to a Position 1.5 m on path 1 (P
dest
) at a
maximum speed of 0.5 m/s (V
max
), and acceleration/deceleration of 1 m/s
2
(A
max
).
2. The HLC routes the order to the appropriate node controller.
3. The node controller generates a motion order and sends it to the appropriate vehicle
master (motor controller for the motor where the vehicle is located).
4. The vehicle master generates a motion profile that is based on the order. Every update
period (~1 ms) a new position, velocity, and acceleration setpoint (P
set
, V
set
, and A
set
)
are calculated.
• As the vehicle moves, the master acquires empty blocks ahead of the vehicle
that the vehicle can move into based on the current motion order for the vehi-
cle. A block is defined as an independently controlled coil (see Table 3-2 on
page 82 for details), no two vehicles are allowed to occupy the same block.
• The vehicle master uses the position of the most recently acquired block far-
thest from the vehicle as an interim destination (target) to calculate the next
profile setpoint (P
set
, V
set
, and A
set
).
• The vehicle master handles all collision avoidance to make sure brick-wall
headway is maintained between vehicles.
5. The vehicle master uses the profile setpoints as inputs to control the vehicle position.
During the move, vehicle data such as actual position, velocity, and interim destination
are sent back to the node controller, typically every 100…200 ms. This data provides
the host controller some level of feedback as to where the vehicle is located.
6. The vehicle master continues to generate updated motion profiles that are based on the
order and vehicle control continues based on the new profile setpoints. This updating
continues until the vehicle is handed off to the next vehicle master or it reaches its des-
tination.
The vehicle master hands-off vehicle control to the motor controller in the next motor
as the vehicle moves across motor boundaries. The new master “picks up” where the
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