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Topics - Mike

#21
RV Hardware / Fixed camera lighting upgrade
November 27, 2017, 07:49:31 PM
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.

 

#22
For Sale/Wanted, Suppliers / RV Placer
November 27, 2017, 11:51:47 AM
My listing - if it doesn't sell I'll strip for parts
https://www.ebay.co.uk/itm/202126806030?ul_noapp=true
#23
RV Hardware / Things to do when you first get an RV
November 27, 2017, 02:30:08 AM
Having just set up 3 machines that have been in storage for >5 years I thought I'd write down some notes, particularly for machines that have sat around for a long time.

In rough order of importance :

Back up the cal data from the PC ( \versatronics\rv\dat\rvdata.dat ) before anything else, ideally before moving the machine. The HD may be 20 years old so assume it will die at any moment.
If you can't take the PC, make sure you get the DSP card (ISA, D37 connector) and vision card ( PCI, HDD26 and BNC connectors).

DO NOT MOVE THE FID CAMERA. This will mess up calibration and we don't yet fully know how to recal, and it needs a special jig. Fid cam problems are likely to be bad phono plug connections or failure of the 9V supply which comes from the arm board.
All 3 machines had intermittant fid cam illuminators - looked like the wire had fractured near the illuminator. It may be possible to remove the illuminator with the camera in place. if not, just add a new ring of LEDs round the outside. 

Power up the PC on its own and run dsptest.exe ( in rv folder) and do "quick test" to test the DSP board.

Replace the head O-rings ( Polymax 8x1mm nitrile) and smear some silicone grease all around.

Check that all axes move freely ( XY will be quite stiff, but should be smooth). Apply some silicon grease to the rack if necessary.

If you are re-arranging hardware without the frame, be sure to include an emergency stop ( in series with mains supply to control box). If the head loses position it can inflict damage on itself and surrounding people/limbs rather quickly. Make sure the e-stop is not somewhere it will get accidentally leaned on.

Power up the PC but not the control box and run dsptest.exe ( in rv folder), and so "quick test"

Connect all cables ( D9 on arm, if present, is not used), and place arm in "park" position - second 'limb' pointing left-right, with head just to the left of the back left corner of the base.

Switch control box on, check for any obvious signs of smoke etc. Fid cam illuminator should come on.
RV1s: Fixed cam illuminator is powered from PC & should come on,
RV4s: illuminator is switched by the arm board so may not come on.

Run armtest.exe. This is mostly to test the serial ports are the right way round. Click "test vacuum" / "Test solenoid" - you should hear the vacuum/solenoid valves, if not, try swapping the D9's on the control box.
If there are serial problems it is sometimes necessary to power-cycle the PC to recover.

Once that works, Click "Run" - this will now show signals from the limit switches - only the first 3 and last 2 are meaningful - others may show junk.
Check that you see the signals- lift the head up/down, rotate the theta axis til the slot ring the encoder, and also lift it up ( this sensor sense both rotation index and head pressure for PCB height sensing) . The x/y switches will operate around the home position.

You need to run RVPlace and load a job file to get any further - if loading an existing file, it will usually complain about feeder allocation - just allocate arbitary feeders and parts for now to keep it happy.
The arm should go through its reset sequence, homing each axis. The first time you ever do this, have your finger on the  e-stop button, just in case.

Once up and running :

Check and tidy all wiring, ensure D Jackscrews on arm unit are tight as it vibrates a lot.
IDC Molex cons in  control unit can cause issues, as power is daisy chained between stepper boards - it's a good idea to re-wire in a star  configuration. At the very least check for any signs that the connectors to the stepper boards have got hot and replace if so.

Update the PC to Win98SE. This gives you useable USB for memory sticks and the joypad ( see other hardware stickies), you REALLY want the joypad. W98 also allows networking, but newer NASs may not talk to Win98. You can log in to Win7 machines though ( not tried later) so you ideally want to keep everything on a seperate, backed-up machine for when the old HD craps out.
From memory I think you can just copy over the versatronics folder, rather than reinstalling the software.

Feeders :
Replace all belts. On feeders with adjustment screws, back off all lanes to minimum tension.
Check all pins move freely ( if not you will see tape move back after feeding forward)  - if not, remove and clean the pins. DO NOT USE OIL as this will combine with paper tape dust to form a sticky mess.



#24
RV Hardware / RV Placer
November 25, 2017, 08:10:32 PM
For historic interest only....
I picked up an RV placer along with three RV1s machines recently.
Unfortunately the disk on the PC had died so couldn't fire it up ( anyone got RV Placer software? )
It doesn't use vision but has some sort of optical sensor on an additional motor that can swing up to the nozzle - I think this is some sort of part-shadow sensing system. i have the manual but only mentions it in passing.
All the motion control is via  a board in the PSU box with two Hitachi Z80 processors and 8 full-bridge drivers. I think it connects to the PC parallel port, maybe also one or two COM ports.
At the top of the shaft is an odd assmbly containing 4 red LEDs and a sensor - not sure what this would be for - it does have the rotary index sensor as on later machines. I wonder if maybe it shines light down the shaft for fid sensing?

Open to offers to get it out of the way...

#25
Just got back from rescuing a load of RV kit, but some stuff was left once I'd filled the car.
About 5 or 6 10x8mm feeders and 3 vibs. Rather dusty but were in use up to a coupel of years ago - probably need a good clean and new belts. May also need the -ve supply mod - not investigated the kit I took yet.
I took all of the few small bits ( bars, cables) and am about to start sorting stuff out, but if anyone wants some 10x8s and can collect from Wolverhampton let me know & I'll let you have details.   
#26
For Sale/Wanted, Suppliers / RV2s/parts
November 04, 2017, 05:18:42 PM
In a couple of weeks' time I'll be rescuing an RV1 and two RV2's that were headed for the scrapyard.
To avoid having to hire a van, I'm planning on leaving all the frames and cabinets - these will get scrapped.
If anyone particularly needs frame parts or covers let me know.

There's also about 3 dozen feeders.

I wasn't previously aware of the RV2 - from the pics it looks pretty much the same as the RV1 with no head cover, in different colours and has the connectors on the back instead of underneath.


#27
RV Hardware / Another cause for poor cover tape tension
February 12, 2017, 10:12:55 AM
When feeders have trouble puling the tape it's usually a sign that new belts are needed, but I just discovered another potential cause - several of the bottom pulleys that hold the belt down onto the tape had become quite stiff on their shafts, so more force was needed to turn them.
 
I think maybe dust gets into the bearing - looks like the wheel turns on a brass bush but hard to take apart as the bush just spins - flushing with non-oily solvent and spinning the pulleys seems to ease them off.
#31
RV Software / RV Setup feeder oddities
June 22, 2016, 01:03:17 PM
Noticed some odd behaviour on last couple of jobs :
1) When adding a tray feeder, it seems to add 2 copies
2) After setting up feeders in RV setup, saving & exiting, reloading RV Setup & some feeders are missing or in the wrong place.
If you don't reload RV setup, they appear OK in RV place.

These are not newly defined feeders - any ideas ?


#33
Other low-end Pick/Place machines / OpenPnP
March 30, 2016, 05:46:20 PM
This project may be of interest to anyone interested in DIYing, or converting an old machine.
Looks a like it has a way to go before being really useable but looking promising and it is being actively worked on.
http://openpnp.org/
#34
Useful info on some new-ish low-end machines here, most with some real end-users :

Smallsmt - Chinese desktop machine supported from Germany for non-China customers.
http://www.eevblog.com/forum/reviews/smallsmt-discussion-thread/

TVM802
http://www.eevblog.com/forum/reviews/pick-and-place-machine-tvm802a-tvm802b/
Small desktop machine

Neoden4
http://www.eevblog.com/forum/reviews/neoden-4-pick-and-place/
Rail feed option for long boards and conveyor loading, 4 heads with simultaneous vision.

All look promising in some areas, disappointing in others, but at least there is now some choice in a market sector where up til recently the RV was the only viable option.

Common remaining issues amongst all of them seem to be limited part height, feeder reliability, availability of 24+mm feeders and lack of auto tool change.
And of course Chinese software, which at least appears to be useable, if not as convenient as it could be.

#36
Other low-end Pick/Place machines / Neoden4
December 18, 2015, 10:18:49 AM
This looks interesting :

http://www.neodentech.eu/contents/en-uk/d8_NEODEN4.html
1500mm PCB capacity!

Awful Anglo-Chinglish video
https://www.youtube.com/watch?v=4P7DDSTXIQo

More info here
http://dangerousprototypes.com/forum/viewtopic.php?t=4903&p=62429
Prices for the feeders are:
60USD/Pcs(8MM)
75USD/Pcs(12mm)
90USD/Pcs(16mm)
#37
RV Hardware / RV Head light mod
October 30, 2015, 06:39:50 PM
For a while I've been looking for some side-emitting LED tape to stick on the inside of the head cover to help see thinsg when settingt up feeders.
Recently found this stuff, sold for car light modding : Search ebay for "side emitting LED tape".
Obviously needs turning off during placement to avoid confusing cameras - I just put a small toggle switch on the top of the head cover. There is a convenient 12V supply on the arm PCB.

The sticky backing on the LED tape doesn't feel very strong so I used some thin VHB tape to help hold it down.
#39
I have an upcoming job for installation in Hong Kong, so using a local assembly house would save a lot of shipping cost.
Simple all-SMD PCB assembly, 15x175mm, 20-odd parts, nothing fancy.
Quantity 18K with 4-6 week turnround inc PCB.
Anyone have any good contacts?