Fixed camera lighting upgrade

[Mike]

I finally got round to upgrading the illuminator on the up-facing camera, and I'd highly reccommend it as it  makes it pretty much immune to ambuient light, and gives a clean image of an 0805 R with a threshold adjust range of 0 through to 60.

I used a ring of white LEDs, as these are way more efficient than red, so can run at 15mA for low heat and long life and still be super-bright.
I pulled the LEDs out of the old ring and fixed the new PCB on it for easy mounting. 
I stopped the lens down to minimum, and also reduced the shutter time ( My cam has a rotary switch on the back to set this - the cam I took off an RV1 didn't - may need a neutral density filter if not, or dim the leds down a bit).

I also made a new ring for the fid cam as it fitted inside the hole of the main PCB. I'll stick this over the existing illuminator to avoid disturbing the fid cam position.

I used a homebrew PCB - happy to share gerbers if anyone wants to get proper PCBs made - they are single sided.

 

[trev]

Yes please on the gerber. Do you have a part number for the white leds?

[Mike]

PCB files attatched :
gerbers ( single sided, 55x52mm)
ident drawing  showing LED polarity ( Leds have a very hard to see notch on the cathode)
top mirror PDF for printing homebrew PCB artwork
DXF of routing outline

LEDs are Osram Duris E3, e.g. https://uk.rs-online.com/web/p/visible-leds/8108196/  or search "LCW JNSH" at your favorite distributor (There are lots of options, mostly different colour temperatures)
Resistors are 1206 100R ( for 12v supply)

Fid cam board needs an external resistor - adjust for brightness, around 100-220R.

I glued a short length of PVC conduit to the diffuser ring to reduce glare from the edge of the LED ring

[alanambrose]

Very Nice,

I'm up for some PCBs and happy to contribute if anyone is sending them out, otherwise I'll add them onto our next order here.

Alan

[alanambrose]

BTW are there any problems / gotchas extracting the fixed camera / lighting or is that fine?

Alan

[Mike]

No - it's fairly well aligned by the mount, and the factory cal menu has an easy centring adjustment mode.
Just mark the side so it goes back teh same war round, and ensure it sits square in the mount. 

[alanambrose]

Hi Mike,

>>> I stopped the lens down to minimum, and also reduced the shutter time ( My cam has a rotary switch on the back to set this - the cam I took off an RV1 didn't - may need a neutral density filter if not, or dim the leds down a bit).

On my RV1S it's a Watec WAT-308A with a COSMICAR/Pentax 16mm f1.4 TV lens which doesn't have a shutter setting. The camera, lens and machined mount parts all look nice quality. If you made a note, which camera do you have there in your 4S?

>>> I glued a short length of PVC conduit to the diffuser ring to reduce glare from the edge of the LED ring

Is this mounted above the diffuser pointing towards the part?

Alan

[Mike]

Hi Mike,

>>> I stopped the lens down to minimum, and also reduced the shutter time ( My cam has a rotary switch on the back to set this - the cam I took off an RV1 didn't - may need a neutral density filter if not, or dim the leds down a bit).

On my RV1S it's a Watec WAT-308A with a COSMICAR/Pentax 16mm f1.4 TV lens which doesn't have a shutter setting. The camera, lens and machined mount parts all look nice quality. If you made a note, which camera do you have there in your 4S?

Mine's a WAT-508. Without the shutter adjustment you may not be able to stop the lens down far enough & may need to either add an ND filter or increase the LED resistors (or add an external series R). The full brightness may be slight overkill - it is a bit uncomfortable to view!

>>> I glued a short length of PVC conduit to the diffuser ring to reduce glare from the edge of the LED ring

Is this mounted above the diffuser pointing towards the part?

Alan

No, below, towards the lens, to reduce internal leakage from the LEDs

[alanambrose]

Inspired by Mike, I've also done a lighting upgrade too and I'm reasonably happy with it. It's slightly different from Mike's in that I chose to keep using 5mm LEDs for the main camera ring and also to interleave red and white LEDs - something about the camera response and the look of the thing. That may be folly. I measure about 8x the ambient light level from each ring and so should be fairly immune to ambient. You might want brighter if you have the luxury of real sunlight. I have not tested the CDFs / re-calibrated the cameras / adjusted the camera response yet. Re the latter, there's one more stop down on my RV1S lens which may do it or I might need a ND filter - which I found you can get OK in the right diameter. I have spare PCBs if anyone wants. Found btw that the reason my fid cam light was flickery was the gnd wire had a break in it where it squeezed passed the camera.

A.




Bigger images here:

http://anagram.net/nuts/Versatronics/Cameras/

[trev]

Have you made a programmable current driver for your boards? Looks very tidy.

I already bought leds Mike used but not gotten around to making the boards yet.

What camera is on your RV1S?

[alanambrose]

>>> Have you made a programmable current driver for your boards? Looks very tidy.

An LT3030 - the '12V' supplies looked a bit iffy.

>>> I already bought leds Mike used but not gotten around to making the boards yet.

I think either approach will be a big improvement. It could be that Mike's use of SMT white LEDs for the main ring will be better. If I ever re-spin I might make suitable for white LEDs as well and make the current adjustment range a bit more accommodating.

>>> What camera is on your RV1S?

Watec WAT-308A with a COSMICAR/Pentax 16mm f1.4 TV lens. From memory, it goes to F16 and takes 27 x 0.5 filters - although the LED ring screws neatly into the filter threads. Mine was set at F8 which (with 8x increase of LED light output from 6EV to 9EV) implies that if necessary I would need to stop down to F16 and add a ND4 filter. There's a space about 42dx3.5 under the diffusers to fit an ND filter if necessary. Without actually trying it yet, I'm guessing that the adjustment can be made in software though. Also, the camera itself has 18dB AGC.

[strand]

When I've bought my RV4s (many years ago) it was in a bad shape (although Groves advertised it as a full working order  ), mostly blind, loosing steps and many other problems, so there are many mods and changes were made during theses years.
I've read that it's vision is reliable only with Plexiglas covers. But it's difficult to adjust machine and feeders with all this shields and metal crate. Also my working space at that time was quite small, so I wanted to use it as a table top machine, which I can remove and store compactly. So I decided to get rid of all metal structures, leaving only MDF table, machine itself and feeders. So the first thing I've decided to modify - vision.
1. For fixed camera I've just glued Rebel 1W white diodes with thermal conductive glue directly to the aluminium ring. They are powered by switch mode constant current driver. They are so bright that camera can work now under direct sun light. To increase contrast I've just inserted a paper tube blacked with black marker. Also I do not use diffuser as it creates unnecessary light spills. Camera was dimmed with fully closed iris and shortest time.
2. For On-the-fly vision I've removed red LEDs and installed 3+3 Rebel 1W LEDs, again with switch mode constant current driver. The camera has no adjustable Iris, but fixed. So I've just cut new iris from a piece of food aluminium foil, blacked it with permanent marker and made a tiny hole in the center with a needle. Then unscrew lens tube and swapped the irises.
    Also I've made a light protection around the arm and head from foamed plastic. This stops any light to get inside the on-the-fly camera compartment. (I'm leaving in Italy and we have a very bright sun  )
3. Fid camera: standard LEDs were substituted with modern high brightness versions. On the photo you can see red light even at day light.

Also I've removed main power transformers an installed 3 switch mode PSU: separated X axis, Y axis and A- +Z-axis. And separate PSU for Arm electronics supply. Machine now works much smoother and never loosing steps.
And just to make easier to identify feeders and loaded components, I've printed labels, laminated them in plastic and glued to the feeder. Now every line is clearly marked and you can write this nonpermanent marker which component is where. 

[alanambrose]

Nice I like the labels a lot. Also interesting to hear the diffusers are not necessarily needed. Do you remember how many stops headroom you had on the lens? You left the shutter the same? I guess we should get some help from the AGC also. (BTW I couldn't get the RV4S WAT-508 spec from watec but I got the RV1S WAT-308A spec here:

http://anagram.net/nuts/Versatronics/Cameras/WAT-308A.PDF )

For my machine I just measured:

ambient lighting - 4 2/3 EV (iso 100)
no diffusers - 12 2/3 EV (i.e. 256x 8 stops over ambient)
1 diffuser - 9 EV (i.e. 12x 3.7 stops reduction)
2 diffusers - 8 2/3 EV (i.e. minor reduction, leaving 16x / 4 stops over ambient)

... which suggests you can get a long way to sorting out the lighting by just removing the diffusers. Also, two layers of diffuser don't seem to give any advantage (or surprisingly disadvantage) over one.

A useful reminder of the value of replacing the PSUs.

Alan

[strand]

I forgot to mention another label on another side of feeder table, which identifies lines when you insert tape.
I've disassembled fixed camera to check settings. Iris =1/16, Shutter speed = 1/5000
A had several times failures because of DC socket on the camera, so I've removed original DC power and Video
connectors and installed mini-DIN socket and lockable plug. No problems with fixed camera any more.

[trev]

Well have some green boards made from Mike's gerber. I have spares if anyone wants a set.

I have an RV1s and wondering if I should do the upgrade or not. Sometimes if things are not broken its not good to try and fix them. But I wonder if it will just improve reliability of component detection generally. The camera does not have any adjustment on it so I believe I will need to control the brightness of the leds to get the best level.

Should or?

Trev