Machine Simulator for MT Connect

In my last post, I talked about how MT Connect works, and how our machine lab isn't yet hooked up to an MT Connect agent (though we're working on it). While I'm waiting for the machines to be connected (and to provide some more lively data) I've created a very basic machine simulator with a fake MT Connect adapter built into the simulation, to provide some action to an agent, ultimately letting me view that action in a web-based tool.

I built the simulator using Microsoft Visio. Basically, I created a fake tool path for a spindle to follow, by just drawing a bunch of node shapes, and connecting them using splines. Then, I created a circle representing the spindle of a machine. The device/spindle shape also holds custom shapesheet attributes mapping device attributes to the device/data item ID's for the machines defined on my agent.

The spindle shape just follows the path of the lines (using a Visio animation routine I built a while back), and at each animation update (set to 2 seconds) it sends our MT Connect agent the current location of the spindle, as well as the current status of the virtual machine (working or broken down). You can see a screen shot of the simulator in action below:

To handle reporting the state of the machine, I just hold a "Next State Change" time on each device object, and on every update see if that time has elapsed. If it has, I flip states (from working to broken or vice versa) and then schedule the next state change event for that machine. Very basic stuff.

I mentioned in my last post that the two agents I've used (available at https://github.com/mtconnect) both allow you to use an HTTP "PUT" request to store information about a machine. So, every time I want to update my MT Connect agent, I just create an XMLHTTPRequest object in VBA (from the Microsoft XML library reference) and open a URL that basically looks like this: http://mtagent/storeSample?timeStamp=(current time)&dataItemID=(data item id for x location, or whatever)&value=(whatever value to store)

With the simulator created, I just set up three device shapes in Visio; one for our Haas machine, one for our Hurco, and one for our Yasda. These machines were already defined in our Devices.xml file on our MTAgent server, which is where our MT Connect Agent gets run from.

By using the simulator to populate data for our real machines, I was able to build a viewer that would dynamically update and show the latest status of all our machines (even though the status was fake). Now, when we get the machines hooked up for real, the same viewer will be able to show the actual status of our machines, which will include a lot more than just spindle X/Y location and if the machine is running or not.

In my next and final post on MT Connect (for the next few weeks at least) I will talk about the HTML/JavaScript viewer I wrote for viewing the current state of our machine lab.