Open Source Safety Protocol

1. "E-stops" create their own safety issues- unexpectedly stopping a machine or system, exposing operators to unexpected events. What happens when on controller in a multi-stage process gets an emergency stop order, and the preceding/following processes continue running?

2. Software-based lockouts are just as hackable as any other software application. They actually expose operators to a greater threat than a manually-controlled physical lockout. If I am going to stick parts of my anatomy inside a machine, I want to have the key to the power lockout in my POCKET, not at some remote computer being monitored by some computer jock who hasn't a clue as to what the equipment looks like or how it performs.

3. International Standardization is good in theory, but, based on my own involvement years ago as Chair of an IEEE standards committee, I am somewhat suspect of major financial interests using such standardization processes to lock out competitors rather than lock out hackers. Sort of like Microsoft trying to force the Universe to adopt their proprietary document format...

Generally, I would have to agree with the first response...not a good idea in the industrial arena. However, automobiles have made great use of computerized controls over the last few decades with great success. I remember how the industry and safety advocates whined and moaned about turning control of your vehicle over to software controls vice sturdy and sure mechanical controls.

Look what happened to Toyota. It turns out that most of their problems were in the mechanical portion of the accelerator, not the software. Mazda started mass production of full electronic steering years ago with nary a squeek from anyone. It goes on so much now that it is accepted as the norm.

I could definitely see this in the future, everywhere...Even in the T-800 series cyborgs!

I don't think it's a question of if

but when & how

automation marches on

freq drives continue drop in price, contactors are becoming redundant

there will always be a push to reduce costs, naturally the big metal contacts are being targeted for elimination

the 1st point in CW's post about e-stops isn't related to the topic

well designed e-stops are integrated into the overall system & shouldn't allow things to go crash

I've been reviewing various safety protocols in order to manufacture a new product. The safety communications are being applied in conjunction with traditional E-Stops and Isolation methods.

The openSAFETY layer appears to have the least self-interest compared with other protocols in IEC61784-3:2010. Other protocols have memberships and source code for sale. With openSAFETY I have a full software and documentation as a free download (I will still need to purchase the standard IEC61784-3-13).

The problem with non-standard communications arises when different systems are connected. A weak link in the chain is when connecting non-safety protocol converters. An adaptor that converts safety protocols (e.g. Fieldbus, CIP, Profibus) to non-safety-ethernet essentially removes all the safety guards provided by the protocol.

openSAFETY appears to have a built in safety-converter, so that any non-safety-communications, and any non-safety converter could be used between different devices. I'm not forced to use Ethernet Powerlink.

By selecting openSAFETY, I will be locking my system into selecting end devices from other manufacturers that support this protocol. By selecting another protocol, I'd be locking both end devices, and the entire communications distribution to specific self-interested organisations.