Motion is an area of control in which Pelican has a particular expertise, both electrical and mechanical.
Our engineers are capable of taking your initial specification, providing a mechanical drive/motor sizing
service, then selecting the correct package to suit your application taking into account both system
requirements and budget.
With over twenty years of experience we are able to select from almost all the major, and some of the
smaller, manufacturers motion offerings to produce a control system tailored to your requirements.
- Vision to motion combined pick and place (Circuit board manufacture and Label application).
- Flying Shear (Metals and Plastics industry).
- Flow wrapping (Food packaging).
- Form Fill and Seal (Confectionary and Snack Food).
- Print Head control (Food packaging).
- CNC (Metals and Plastic).
- Robotics (Welding and Handling).
Below are a sample of the manufacturers used in the applications above.
Allen-Bradley |
Control Technique |
Mitsubishi Electric |
Omron |
Siemens |
Trio Motion Technology |
Below is an example utilising the Trio Motion MC216. Flying Shear plastics industry.
This particular example of code controls an end of line cut length saw commonly found in the extrusion
industry. The software was written and developed for a market leading machine manufacturer supplying
into the plastics market. Product speeds of an accuracy of +or- .1mm could be expected at line speeds
over 20 metres per minute.
Basic Requirements
Rolled tubing is fed via a pinch-roll through a cutter mechanism attached to a ball-screw. The cutter
must synchronise to the tubing and fire an output to activate the cutter at a known point. An encoder
is fitted to the feed rollers and for this simple case we can assume that slippage through the rolls is
negligible.
- The total movement available on the ballscrew is 500mm, therefore the cutter must
accelerate up to line speed, synchronise for the cut and decelerate again within this distance.
- The cutter needs to be fired at a regular position in order to cut accurately.
- For this example we want to cut tubing into 5m lengths. Units are in metres.
Synchronising the Cutter to line speed with MOVELINK We have a maximum of 500
mm
movement on the cutter axis. We will use the 100
mm at either end of the travel for
acceleration and deceleration, leaving 300
mm synced to line speed.
As we can see in the diagram above. our link distance for the acceleeration and deceleration phases
need to be twice the distance moved by the cutter, and whilst in sync the distances will be the same
|
Accel:
|
cutter moves 100mm linked to 200mm on the master
|
|
Sync:
|
cutter moves 300mm linked to 300mm on the master
|
|
Decel:
|
cutter moves 100mm linked to 200mm on the master
|
The resultant
MOVELINK parameters can be determined by adding the component parts together. So,
if our parameters are in metres the command would be:
MOVELINK ( 0 . 5 , 0 . 7 , 0 . 2 , 0 . 2 , link_ax) .
