Show Posts

This section allows you to view all posts made by this member. Note that you can only see posts made in areas you currently have access to.


Messages - alanambrose

Pages: [1] 2 3 ... 7
1
RV Hardware / Re: Power supply issues
« on: February 22, 2021, 01:55:45 PM »

2
RV Hardware / Re: Problem Homing
« on: February 22, 2021, 01:53:06 PM »
Thanks for properly documenting that Steve. Every bit increases the value of the archive to us RV-people :)

Alan

3
Hi,

FYI there's some of these cheap on eBay if anyone wants spares. I've bought a couple but have not tested them and the supplier can't give me the provenance - so anyone's guess whether they're good or not. They do look new though. There's only one up there right now but I think the supplier has a bunch. e.g.

https://www.ebay.co.uk/itm/SANYO-DENKI-PMM-MD-53031-10-PM-5-PHASE-STEPPING-DRIVER/363206181301

Alan

4
RV Hardware / Re: Moving RV
« on: September 10, 2020, 11:14:14 AM »
That's weird I thought I already replied to this...

>>> the arm/table unit just lifts off.

Thanks Mike, I didn't realise that. That worked well and allowed enough weight reduction that the cabinet could be manhandled down some steps.

Alan

5
RV Hardware / Moving RV
« on: August 10, 2020, 10:19:53 AM »
Hi,

I need to move my RV, which involves taking it down a couple of steps, round a few corners etc onto a tail lift. Does the arm assembly detach easily to reduce the weight of the overall cart? If so, how?

Alan

6
RV Software / Re: cw3230.dll
« on: July 31, 2020, 01:57:53 PM »
>>> trapping the instructions which access the hardware using a vectored exception handler

interesting - I don't think it would be so difficult to make or buy the modern day equivalent of the ISA board. I'm thinking it, roughly speaking, does the equivalent of G-code interpret for G-code move instructions. From what I remember, I figured the software decides where it wants the head to be next in r,t,z,a (where r & t & a are rotations) space and calls the ISA board to execute that move with the help of the ramp.sys profiles. Ignoring the tool-changing etc bits of G-code, that's what the typical 4-axis G-code interpreter does. In fact making your exception handler spit out G-code moves on a serial port would be most of the way there :)

Alan

7
RV Software / Re: cw3230.dll
« on: June 05, 2020, 12:13:29 PM »
Wow, I'm amazed it runs under Win10.

Alan

8
RV Software / Re: Step and Repeat
« on: June 02, 2020, 02:22:57 PM »
Yeah I have noticed something like that. I had some improvement by measuring the actual repeat vs the theoretical repeat. That is assuming you had the board house do the panelisation.

A.

9
RV Software / Re: Calibration
« on: April 18, 2020, 05:47:36 PM »
Hi,

No I don't believe so - it's CCIR as far as I know. Unfortunately my RV is about 85 miles away atm otherwise I would check. One possible test is to check the Imagenation utility sees your FID & main cams OK. It might even give some camera data, sorry I can't remember whether it does. I have found though a copy of the PXC 200 docs and utilities:

http://anagram.net/nuts/Versatronics/PXC%20200%20card/

There are two versions of the utilities there - which version I used I'm not sure.

Alan

10
RV Software / Re: Calibration
« on: April 16, 2020, 06:28:04 PM »
Hi Micky,

I think you boot into DOS and the utilities are in an 'Imagenation' directory - it was 3 years ago that I used them.

An image for the sleeve for the cal camera (assuming a WAT-704R) that I designed and had made is below - I've never had the time to test it though. From memory, it was meant to mount instead of the 'nozzle pick-up' - the thing with the two o-rings on - with some slits for the a-axis optical homing switch.

Alan


11
RV Software / Re: Calibration
« on: April 16, 2020, 04:45:52 PM »
Hi,

I always guessed that the cal camera was the same as the fid camera - mainly because it needs to be fairly small and presumably if you had written a bunch of camera code, you would tend to want to use some of the same code for the cal routines - which I'm suggesting implies the same camera. I can always be wrong. If I remember correctly the fid camera is a Watcom WAT-704R G3.8 - and you can still buy these new (for about £125 + VAT). It would be worth double checking I have remembered the right camera. The specs are here:

https://www.watec.co.jp/English/eng_spec/WAT-704R_G3.8_eng.pdf

Although the Wacom has AGC etc, I would have thought your eBay camera would work as it seems to have similar specs. I remember that there's some camera routines (maybe DOS based) that allow you to test the camera capture from the Imagenation board outside of the RV software. I can dig out my CAD for the holder for the Watcom camera if anyone wants to 3d print that.

Alan

12
RV Hardware / Re: Tool loading and unloading problems
« on: February 20, 2020, 02:16:10 PM »
Hi,

One thing that took me a while to figure out originally - is that I had one tool that didn't load well. Turned out it had a mostly blocked orifice (can I say that on here :) ) - and the resulting back pressure was stopping it from being pushed on properly.

I've tried the tool block height cal a few times both with and without the nozzle and in both cases the results didn't seem to make much sense - so I reverted to the old height - but I would like to learn the right call method too as I think I have a small error on pickup height.

Also, anyone know how to do the fid cam cal? A member on here recently implied they did.

I've been using my RV a lot over the last few days and by-and-large it has been working out well. I sure wish I had access to the source code though so I could make some UI improvements.

Alan

13
Hi,

I failing to understand the relationship between the 'Setup Pcb' & 'Fiducial Correct' dialogs. I should say my 'references' are always the same as my 'fiducials' which are always spare footprints on the bottom left and top right of my pcb.

In 'Setup Pcb' I set the X,Y of Ref 1 & 2. I assume the Z value in this dialog is largely irrelevant, as the next step is to measure the board height? If so - so far, so good - this sort of makes sense as the RVS clearly needs to have am accurate sense of the PCB surface.

But then in 'Fid Correct' I set the X,Y again of those same points. Presumably as the basis for placing the components.

Is the 'Setup Pcb' only establishing the board surface? In which case, the X,Y of Ref 1 & 2 are not super-important? But the 'Fid Correct' positions are key to establishing the position of all the components? Is that right or am I missing something?

TIA Alan

14
RV Hardware / Re: video capture card
« on: January 17, 2020, 05:38:12 PM »
Apologies, that sounded a bit grumpy. What I meant to say was that there's a lot of great information on here with a great signal/noise ratio :)

15
RV Software / Re: Calibration
« on: January 17, 2020, 01:16:40 PM »
Hi,

>>> We acquired some of the calibration kit from a sale of RV's that we purchased for spares.

Ah, I hadn't noticed that there was some progress with this. This is very encouraging :)

>>> We were missing the camera that aligned with the centre of the nozzle spigot - it is vital that this camera is aligned 100% coaxially with the nozzle spigot and plumb vertically.

if that helps, I created some cad and a 3d print to hold, what I assumed was another fid-style camera.

>>> In any event the most important item is the screen.

I was hung up on where the dot screen was located relative to the positioning dowels. Is it possible to measure that or post an image with the grid in position and a ruler showing the distances? There are a few logical positions and I couldn't figure out which made the most sense.

>>> I have set the fiducial camera using the 'prestick' method as shown to me by DC with no problems whatsoever.

Can you describe that in more detail, I would love to setup my fid camera properly?

>>> There was a lot of postulating about two sets of data points and if it could relate to the fiducial camera, and to be honest I do not believe it does.

This is my interpretation ...

Firstly, there are two clear matrices of positioning cal data in rvdata.dat. Secondly, looking at some general information about scara arms and algorithms - it seems to be a general strategy to (a) use geometry to get from desired Cartesian nozzle x,y on the bed to rotational a,b and then use (b) adjustments based on measured data to get a more accurate position. I'll see if I can locate again some articles I found on that. That points to a tactic of figuring out which square you're in on the bed and then using the cal values and 2d interpolation to get the accurate fix. Hence, you need some data showing how far off the real numbers are from the calculated ones. That points to using an accurate physical grid (i.e. the photoplot) and a cal routine to calculate the adjustments...

Yeah, since the fid camera is located a fixed distance from the nozzle it wouldn't be strictly necessary to have two adjustment matrices. However, if you've already written the cal routine code based on a camera mounted on the nozzle holder, it's perhaps the easiest course of action to just use the same code for the fid camera - particularly if they're the same camera model :)

Alan

Pages: [1] 2 3 ... 7