Statistical Weigher Simulator

ProtoLink was asked by a major snack food manufacturer to provide a software application that simulates a collection of Ishida Statistical Weighers, which are machines responsible for dumping specified amounts of product into a package.  The resulting multithreaded Windows NT application allows users to configure the machines and simulation parameters through a Windows Explorer-like interface.  Like the actual machines, the simulator communicates with a host computer over ARCnet and Ethernet.

Separate threads of execution simulate the behavior of each configured Ishida machine.  Two methods are provided for generating sample dump weights.  In the default mode, sample weights are automatically generated using a Gaussian random number generator.  In manual mode, sample weights cycle between a set of values entered by the user.  The user configures the dump rate for each machine, which controls how often the machine simulation threads wake to perform their work.

The software also allows the user to trigger special machine events that result in unsolicited messages being sent over ARCnet or Ethernet to the host computer.  These events can also be scheduled for repeated triggering according to an arbitrary schedule or in a periodic fashion.

The simulator allows our client to test changes to host software and operational procedures in a laboratory environment before going live on the plant floor.