VDM

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VDM
Brian Steensgaard, 20043835_at_iha.dk Henrik
Karmisholt Grosen, 20043836_at_iha.dk Rasmus Oudal
Edberg, 20043839_at_iha.dk
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Project
Production Cell
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Purpose
The purpose of the production cell is to take
metal plates from the feed belt to the press,
which will perform some (time consuming)
treatment of the plate. The treated plate is then
moved from the press to the deposit belt where it
leaves the unit. Plates are moved from the feed
belt to the press using arm A of the robot, and
from the press to the deposit belt using arm B of
the robot. The two arms are of fixed length and
height, and are fixed to each other (i.e. 90
degrees).
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Semantics

1. Plate is placed on feed belt.
2. Plate is moved from feed belt.
3. Plate is removed from press if one is already
   placed, and a plate is placed on press.
4. Plate is placed on deposit belt.
5. Plate leaves production cell.

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Sensors And Actuators

• Sensors
• Rotation sensor - controls the rotation of the
  robot arms.
• Light sensor - senses an plate.
• Actuators
• Motor - control the speed of the two belts.
• Lamp - provides input to the light sensor.
• Electro Magnet used to pick up the plates

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Project Goals

• We want to
• Model the sensors in an OO model
• Model the actuators in an OO model
• Model the reactive control logic in an OO model
• Prove safety requirements for sensors
• Prove safety requirements for actuators
• Prove safety requirements for control logic
• We do not want to
• Prove liveness properties (eg. optimization etc)
• Consider realtime requirements
• Consider distributed computing

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Safety requirements

• Sensor safety requirements
• Sensor reading may not be beyond possible range
• Actuator safety requirements
• Machine parts may not be instructed to move
  beyond its limits
• Control logic safety requirements
• Machines must not collide
• Metal plates may not be dropped outside feed belt
  and press
• No more than one metal plate may be placed in the
  press
• Metal plates must never fall of the end of the
  feed belt