Operation
Theory of Operation
QuickStick HT User Manual 233
Rockwell Automation Publication MMI-UM007F-EN-P - September 2020
Block Ownership
The minimum distance two vehicles can be from each other is 6 mm, since the end of each
vehicle maintains a space of 3 mm from the end of the owned motor block in the direction of
motion for anti-collision. This minimum distance is based on the length of the vehicle, not the
magnet array. Figure 6-4 shows that when any portion of a vehicle is over a motor block, the
vehicle owns that whole block. The vehicle positions in Figure 6-4 show that the vehicles
could be closer together, but vehicle separation is based on the length of the configured pay-
load or vehicle and block ownership, not the length of the magnet array.
Figure 6-4: Representation of Block Ownership by Vehicle
When vehicles are placed in queue, they get as close to their commanded position as possible
without violating the block boundaries as shown in Figure 6-4. When trying to create stations
that put vehicle next to each other, the vehicle positions and the space that a vehicle occupies
in a motor block must be considered, as shown in Figure 6-4.
Block Release
The drive for each motor releases ownership of blocks once the vehicle exits the block and is
at least 3 mm away from that block. Block ownership is also released if the vehicle is deleted.
Anti-Collision
The QuickStick HT transport system allows only one vehicle per motor block. This block
allocation is the basic rule on which the anti-collision feature of the QSHT transport system
controls is founded. Since two vehicles are not allowed to be in the same motor block, they
cannot collide. This block allocation affects how many vehicles can fit on a motor or path.
Also, the magnet arrays on the vehicles have a slight repulsive force that causes them to pas-
sively separate from each other a short distance when they are manually pushed together and
not being servoed (actively controlled). The distance they passively separate varies based on
vehicle and guideway conditions (including friction).
The vehicles can be commanded to a tighter spacing but this spacing requires constantly driv-
ing the motor to force them together. They can be commanded to a pitch where they are prac-
tically in contact with each other but if this constant, close position condition is held too long
the motors reach a thermal limit and shut down. This tight spacing can be done on occasion
but it cannot be a standard part of a process.
3 mm
Space Vehicle Occupies
Downstream Motion
Vehicle
Motor
Block
Magnet Array
To Next Page
Loading...
Need help?
General
