ILDA Compliant Projector Safety Board...

[300EVIL]

Hey Everyone!
After reading some posts and PM's from other members it seems that a good number of people are interested in making their projector ILDA compliant and possibly variaced. I also think this is a good idea and have been working on this project for a couple months now and I figure I'd bring it up to see how much interest there is.

What I have is a circuit, soon to be board, that can be easily integrated into any projector with all the required interlocks to meet ILDA and CDRH standards. It would be very simple to wire yet complex enough to not be easily defeated. Now it's no medical laser safety system but it's damn good. It's complex enough to be compliant and safe, but simple enough to not get in the way. I'm now moving into the stage of working out all the bugs to make sure it will work correctly with different pieces of equipment and won't lock up the projector in the middle of a show.

The finished project will have features such as:

• Modulated ILDA cable interlock loop
• Key switch interlock
• Projector case interlock
• 1-10 second laser "power on" delay
• Pushbutton on/off controls that reset for power failure
• External interlock loop for E-stop and system indicator lights
• Shutter driver
• Laser driver PS relay driver

All of this stuff in a tiny board approximately 3" X 2" minus the peripheral devices such as buttons, keyswitch and relays. I'm also contemplating adding a scanner feedback circuit for detecting scanner failure. Although, it seems that most Chinese scanners do not provide this output. Another plan is to add the ability to easily connect an hour meter that will only count when the laser driver modules are in standby/lasing.

As for price.... well, that's still TBT. Though, I can't imagine the board itself will be more than $40 or so. Don't hold me to it... After the key switch, a couple of relays, shutter(GM-20 or similar), interlock switch, push buttons, LED indicator lights, a cable and E-stop button with project box, the price goes up a little more. I may supply all this stuff in a full kit, I may not. This is all still to be determined.

Anyway, after all these components are installed in your case along with the board. All you'll need is a 5-30VDC supply that comes on with the main power switch and a 12V power supply that the board can tap power from for running the coiled devices such as shutter and relays.

So, I'd like to see a show of hands of who would be interested in getting one of these boards and would also like to see some comments and suggestions on how I could improve this project to fit everyone needs and wants.

Thanks Everyone!
Adam

[mixedgas]

The finished project will have features such as:

• Modulated ILDA cable interlock loop
• Key switch interlock
• Projector case interlock
• 1-10 second laser "power on" delay
• Pushbutton on/off controls that reset for power failure
• External interlock loop for E-stop and system indicator lights
• Shutter driver
• Laser driver PS relay driver

endquote
Add a ramping driver for the shutter, ie has pull in and hold in current settings that are different. I'm tired of "cooking shutters.

make sure the button inputs/keyswitch inputs are buffered and thresholded, so you can remote your stop/start. Nothing that a current mode signal would not do, as opposed to a voltage mode signal, ie switches need to pass 10 ma to be valid. (CDRH likes current mode switching)

steve

Steve

[buffo]

One more request: in my opinion the projector must never start unless commanded to by the operator. That is, you have a 'run' button that will start/re-start the projector. If any interlock condition fails the projector, the projector will not re-start until the 'run' button is pressed. (Not all projector interlocks do this. For example, if someone yanks the ILDA cable out and then plugs it back in, most projectors will resume lasing and scanning with no operator action at all.)

Adam

[sugeek]

I am interested in seeing something like this but after Steve has vetted it ... I would say having an option for just the board, and for a board + goodies kit. I say this because for my current build I have all of the extra parts but have not finished the circuit for the shutter driver interlock etc, so good timing I can hold off a bit to finish that stuff and focus on lasers and optics. Keep us informed of your progress, and price points!

-Adam

[daedal]

After the key switch, a couple of relays, shutter(GM-20 or similar), interlock switch, push buttons, LED indicator lights, a cable and E-stop button with project box, the price goes up a little more.

Thanks Everyone!
Adam

So, why use a GM-20 as opposed to a spring-loaded Ledex solenoid (besides speed)? Just out of curiosity.

Also, wouldn't the galvo need to be 'told' to go back to an "off" position? The spring-loaded solenoid, in my opinion, is fast enough for a shutter, and also has a preset "off" position when no voltage is applied to it... Not to mention the price difference as well...

All the medical shutters I've seen have Ledex solenoids in them... or is something off here?

--DDL

[carlos3621]

why not also include the sections, in the laser product report,filled out with the drawings/ circuit schematics, for these safety features.
one less thing for the end user to worry about, when filling out the laser product report

[allthatwhichis]

I have had something like this in my head for about 6 months; I have been nagging DZ to try and build an external "box" to house all the electronics that would basically plug into the back of any projector and just run a wire into the projector to signal the shutter once it is installed.

[carlos3621]

Now thats what im talkin about!
this is a good step forward in making it easier to get your projectors certified.
go 300EVIL!

[sugeek]

So, why use a GM-20 as opposed to a spring-loaded Ledex solenoid (besides speed)? Just out of curiosity.

Also, wouldn't the galvo need to be 'told' to go back to an "off" position? The spring-loaded solenoid, in my opinion, is fast enough for a shutter, and also has a preset "off" position when no voltage is applied to it... Not to mention the price difference as well...

All the medical shutters I've seen have Ledex solenoids in them... or is something off here?

--DDL

I second the solenoid driver I have a couple sitting here I plan to use, spring-loaded and photo sensor fail safe... But if you have GM-20's it is your circuit!

-Adam

[mixedgas]

I second the solenoid driver I have a couple sitting here I plan to use, spring-loaded and photo sensor fail safe... But if you have GM-20's it is your circuit!

-Adam

GM20s move at warp speed compared to a solenoid and they dont "clunk" out loud. Other then that, no difference, they both spring return.

Steve