PC Based Automation » pc based automation

Automating the Baja 1000

David Novak — Thu, 18 Nov 2010 19:53:17 +0000

Taking PC Based Automation to the Extreme!

If you’ve been getting the Dajac newsletter, you know that we have teamed up with Dallas Design and Technology (DDT) to prove that PC based automation makes sense, even in the toughest conditions. Read Dajac Goes for a Ride – Baja Style for complete details.

Today marks the beginning of the race!

The Expert I/O 1000 has been installed and Mark is in Baja with the car, preparing to launch. The car is #404 and is scheduled to start the race at 1:00PM PST.

The starting line is being streamed live at www.BAJA1K.com. They will also be shooting semi-live video from all over the course in addition to letting you get in the driver’s seat with your favorite team with real time vehicle tracking.

Go check it out!

I’ll publish more details when Mark returns.

Use Microsoft Office for Your Next Automation Project

David Novak — Sun, 29 Aug 2010 16:02:02 +0000

Automate with Office

If a software development platform can call a DLL, it can be used to control the Expert I/O 1000. Microsoft Office with Visual Basic for Applications (VBA) is no exception.

For most people, Office would be the last tool they would consider for PC based automation, but in some cases it might be the best. For example, you could easily log data to an Excel spreadsheet or Access database as you collect it and once it’s in these applications, it’s simple to manipulate, plot and report the data.

Office provides two big advantages.

Low start up cost.
Short learning curve.

The main advantage of Office is its low start up cost. Practically every computer in existence has Microsoft Office installed. If you don’t need the features of a full fledged software development suite, you can save a bunch of money by using a tool that is already on your computer.

The other big advantage of Office is that many people who aren’t software engineers know a great deal about VBA. It is used all the time for office automation by non-engineers. Microsoft has given us a development tool that can be used by everyone, not just geeky software engineers.

Controlling the Expert I/O using VBA in Excel is very easy. Here is the entire code of a VBA macro I created. The entire subroutine is only about a dozen lines.

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' Expert I/O API.
Declare Function eioOpen Lib "eio.dll" () As Long
Declare Function eioClose Lib "eio.dll" () As Long
Declare Function eioClaimInterfaceEz Lib "eio.dll" (ByVal ModelId As Integer, ByVal SerialNumber As Long, ByRef Handle As Long) As Long
Declare Function eioReleaseInterface Lib "eio.dll" (ByVal Handle As Long) As Long
Declare Function eioDioSetPull Lib "eio.dll" (ByVal Handle As Long, ByVal Port As Long, ByVal PullLevel As Long) As Long
Declare Function eioDioSet Lib "eio.dll" (ByVal Handle As Long, ByVal Port As Long, ByVal PinLevels As Byte) As Long
Declare Function eioDioGet Lib "eio.dll" (ByVal Handle As Long, ByVal Port As Long, ByRef PinLevels As Byte) As Long

' Constants
Const MODEL_ID As Integer = 1
Const SERIAL_NUMBER As Long = 99
Const INPUT_PORT As Long = 0
Const OUTPUT_PORT As Long = 2
Const eioDIO_PULL_3_3 As Long = 1
Const eioDIO_PULL_GND As Long = 2

Sub DigitalIo()
Dim Handle As Long
Dim PinLevels As Byte
Dim ReturnCode As Long

' Open API and get handle. Normally, this would be done only once at the
' beginning of the program. It has been included here to keep the
' example as simple as possible.
ReturnCode = eioOpen()
ReturnCode = eioClaimInterfaceEz(MODEL_ID, SERIAL_NUMBER, Handle)

' Set digital pulls.
ReturnCode = eioDioSetPull(Handle, INPUT_PORT, eioDIO_PULL_3_3)
ReturnCode = eioDioSetPull(Handle, OUTPUT_PORT, eioDIO_PULL_3_3)

' Set output levels equal to cell in spreadsheet.
PinLevels = Cells(3, 5)
ReturnCode = eioDioSet(Handle, OUTPUT_PORT, PinLevels)

' Get input levels and set spreadsheet cell to the value read.
ReturnCode = eioDioGet(Handle, INPUT_PORT, PinLevels)
Cells(5, 5).Value = PinLevels

' Clean up. Normally, this would be done only once at the end of the
' program. It has been included here since we included eioOpen() and
' eioClaimInterfaceEz() in this subroutine.
ReturnCode = eioReleaseInterface(Handle)
ReturnCode = eioClose()

End Sub

Lines 27 and 28 initialize the Expert I/O API. Lines 31 and 32 set the output voltage level and input pull up state. These lines would normally be placed in a subroutine that runs once at the beginning of the macro. The initialization does not need to be performed for every I/O access.

Lines 35 and 36 set a digital output port to the value in the spreadsheet at E3.

Lines 39 and 40 read a digital input port and write its value to the spreadsheet at E5.

The interface is released and the API is closed with lines 45 and 46. As with the initialization, this cleanup only needs to be performed once at the end of the macro.

As you can see, writing a VBA macro to control the Expert I/O is an incredibly simple task. So for your next automation project, don’t forget to consider Microsoft Office. It might be just what you need.

Click here to download the Excel file that contains this macro.

Dajac Goes for a Ride – Baja Style

David Novak — Fri, 30 Jul 2010 14:43:58 +0000

Taking PC Based Automation to the Extreme!

Being headquartered near Indianapolis, it’s only fitting that Dajac be involved with racing. However, this will be a much different experience than the well controlled conditions at the Indianapolis Speedway. This year, Dajac’s Expert I/O 1000 will be put to the test in the rough and dirty Baja 1000 on the Baja peninsula November 17th through the 21st.

The Baja 1000 is a thousand miles of the most grueling terrain. Racers and their vehicles endure water, sand, mud and wind as they careen through the course at top speeds up to 120 mph.

Dajac is teaming with Dallas Design and Technology (DDT), a leading edge industrial integrator, to prove that PC based automation is a good choice for even the toughest projects. DDT will replace a large array of switches, gauges, a large format GPS and a laptop with a rugged touch screen PC and an Expert I/O 1000.

Dajac and Dallas Design and Technology team up to race in the Baja 1000.

A complete graphical user interface (GUI) and the data acquisition and control algorithms will be created for the PC using Visual Basic (VB.net). VB.net is a great tool for projects like this, but literally any PC software development environment could be used.

“The use of PC’s for industrial control is becoming more prevalent,” says Mark Stevens, Owner of DDT, “this project will allow us to prove the robustness of a properly integrated PC control system.”

I couldn’t agree more with Mark. A great deal of effort is being expended by the industrial controls market to design products that bolt PC features to outdated technology. Why not make your life simple and leap frog this intermediate step? It is only a matter of time before the PC is the de facto standard in industrial control.

Keep your eyes on the Dajac web site for updates! I will be posting more detailed information as we progress.

Tied In Knots USB Extension Guide

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Dajac and Linxter Help You Dodge Bullets

David Novak — Mon, 01 Mar 2010 13:50:14 +0000

The Ultimate Smart Grid

When I think of smart grids, one of the first things to pop into my mind is Keanu Reeves dodging bullets in The Matrix. That was the ultimate smart grid! We’re not even close to that, but with the internet, we are becoming more and more connected. Everyday, there are new initiatives to connect us to others and to connect machines to other machines.

Recently, there has been a great deal of talk about creating a smart power delivery system. This “smart grid” will have the ability to use electricity more efficiently by bridging the gap between the devices that use electricity and the suppliers of electricity. For example, a manufacturing plant may have a process that must run once a day with no strict time of day requirements. The smart grid will allow the plant to monitor electricity prices and only activate the process when the price of electricity falls below a specified threshold.

An example more pertinent to typical consumers is to control residential appliances based on electricity demand. With a smart grid, you will be able to load the washing machine and let the grid turn it on during non-peak (lower cost) times.

In addition to providing energy savings for the end user, the power companies will benefit from devices that report energy consumption. Using this consumption information, power companies will be able to operate more efficiently by leveling grid capacity to ensure energy is available when and where it is needed.

But how do you implement a smart grid? You need two pieces, a way to communicate with locally installed equipment and a way to control that equipment. Dajac and Linxter together provide the solution.

Dajac’s Expert I/O modules are the “last mile” technology. They allow a computer to easily control electronic devices.

The remaining piece, the communications, is made effortless with Linxter’s software library. This library exposes a simple interface and takes care of the grunt work to give you a reliable and secure Ethernet communications channel across even the most unreliable links.

Over the next few weeks, Dajac and Linxter will unveil a smart grid proof of concept that will allow you to see these technologies in action and control them from anywhere in the world. Read the Linxter blog for more information about this event and keep an eye on the Dajac and Linxter web sites for the unveiling!

Tied In Knots USB Extension Guide

TIED IN KNOTS — A Must-Have Guide to Untangling USB Extension Options for PC Based Automation

PC Based Automation Continues to Grow

David Novak — Sat, 02 Jan 2010 05:01:55 +0000

PC Based Process Control

I was cleaning up over the holidays and came across a couple articles that I had saved from earlier in 2009. I’m sure you’ll find them interesting. Both articles describe how people are taking PC based automation to the next level to reduce cost and integration time.

The first article, PC–Based Controls Help Freeze Escalating Energy Costs, from ControlGlobal.com (May 13, 2009) explains how a company used PC’s to standardize control in multiple plants. Not only were they able to standardize, but the power of the PC allowed them to drive cost out of the process by using highly advanced control algorithms. Implementing the algorithms with PLC’s might have been possible, but the solution “would have been unwieldy and impractical”. Using the PC allowed them to model the process in real time to design the most efficient algorithm. In addition to better algorithms, PC control made is very simple to communicate with the rest of the plant and even between plants.

The second article, USB Flexes Its Industrial Strength from Electronic Design (May 23, 2009), describes the multiple advantages of USB in PC based automation. It explains that although the overall speed of USB 2.0 is slower than that of Gigabit Ethernet, USB continues to be a great choice because of it modularity and the lack of need for Gigabit speeds. An important point that the article misses is that USB can be implemented in such a way as to have a guaranteed maximum latency (as is done in the Expert I/O 1000), whereas Ethernet depends on the number of devices attached to the node. The article goes on to explain that USB speed is soon to surpass Gigabit Ethernet. The new USB 3.0 specification increases the bandwidth to 5 Gigabits/second.

Make no mistake, PC based automation is alive and well and continues make gains into process and control applications where PLC’s once easily dominated.

Tied In Knots USB Extension Guide

TIED IN KNOTS — A Must-Have Guide to Untangling USB Extension Options for PC Based Automation