0 to 360 degree camera and MORE!

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0 to 360 degree camera and MORE!

Postby Viewmaster » Sat Aug 27, 2016 11:58 pm

DANGER
Never look directly at any laser or its reflection in a mirror.
Never shine it in anyone's eyes, including making a cat chase its image on the floor.
Never shine it into the sky, especially when aircraft are around.


Taking further the Lego camera shown here.........
viewtopic.php?f=5&t=2153

My old XP Dell laptop can draw 300 lines with 300 pixels in each line, in random colours for each pixel, in about 1 second
just using simple BBC BASIC as a speed test. ( Have not yet received a photo cell I have ordered).

If the laser were turret mounted it could spin around 360 degrees instead of oscillating back and forth, line by line
as the Cambridge version does. This will enable very much faster scanning and gives the following.....

A very simple change to the PC software (I am already experimenting on that)) could plot any part of the
rotary output to the photo cell, thereby having any scanned width of picture from 0 to 360 degrees !!

In fact if the frame movement were also 360 degree movable one could scan a complete SPHERE!!
The sync point on the machine can be moved to any 'degree position' to 'tell' the software when to start a new line

One would have to be very careful of ones eyes at 360 as the laser would be scanning a complete circle and up and down
too for each frame. The whole area were you were would be in the laser beam!

ALSO, if the whole contraption were on a hinge it could be moved through 90 degrees to get VERTICAL scanning,
the software simply switched to give verticality on the laptop screen.

So hor/vert scans in any width and any with any number of lines and any heights can be achieved just by
simple changes to the software variables.

Now to speed it all up and add versatile NBTV to my old laptop. :D Just kidding!
Last edited by Viewmaster on Fri Sep 02, 2016 2:17 am, edited 2 times in total.
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Re: 0 to 360 degree camera and MORE!

Postby Harry Dalek » Sun Aug 28, 2016 6:43 pm

Hi Albert
Got off Resources ' :wink: don't think there have been so many replies down there !

Your a master of the mechanical and electrical so i know you can get it going ,i will watch the build with interest...always like picking up tips ,i know this is to hard for me very much so on the computer side of things ~!
The electromagnetic spectrum has no theoretical limit at either end. If all the mass/energy in the Universe is considered a 'limit', then that would be the only real theoretical limit to the maximum frequency attainable.
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Re: 0 to 360 degree camera and MORE!

Postby Viewmaster » Sun Aug 28, 2016 11:27 pm

Harry Dalek wrote:Hi Albert

Your a master of the mechanical and electrical so i know you can get it going ,i will watch the build with interest...always like picking up tips ,i know this is to hard for me very much so on the computer side of things ~!


Harry, with circuits I just copy someone, else I cannot do any project.
I am the electronic dunderhead of NBTV :D

Don't be put of by simple BBC BASIC, Harry. Just a question of IF this then THAT, ELSE something else. etc
Just simple logic although I found that fast inputting 8 bits from the old laptop printer port was a bit of a pig,
but there again, it was others on the net that steered my little ship in. :D

Put a BBC BASIC emulator (many are free) onto a laptop and it storms away,
much faster than on the old Beeb micro of old............ And one can have 255 x 255 x 255 colours !!

Will post here if more progress......or otherwise. Fortunately little electronics is required
for The Slow Nip. :lol:
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Re: 0 to 360 degree camera and MORE!

Postby Harry Dalek » Mon Aug 29, 2016 3:04 pm

Viewmaster wrote:
Harry Dalek wrote:Hi Albert

Your a master of the mechanical and electrical so i know you can get it going ,i will watch the build with interest...always like picking up tips ,i know this is to hard for me very much so on the computer side of things ~!


Harry, with circuits I just copy someone, else I cannot do any project.
I am the electronic dunderhead of NBTV :D

Don't be put of by simple BBC BASIC, Harry. Just a question of IF this then THAT, ELSE something else. etc
Just simple logic although I found that fast inputting 8 bits from the old laptop printer port was a bit of a pig,
but there again, it was others on the net that steered my little ship in. :D

Put a BBC BASIC emulator (many are free) onto a laptop and it storms away,
much faster than on the old Beeb micro of old............ And one can have 255 x 255 x 255 colours !!

Will post here if more progress......or otherwise. Fortunately little electronics is required
for The Slow Nip. :lol:


You have done lots of good work there Albert the smallest Nipkow for our hobby and the matrix display so on all stuff most of us could not do so its very helpful seeing what you can do tips and such .
I had a little computer many years ago that did basic use to drive me nuts having to type pages of code to just get some sort of rainbow display when loaded from a cassette ...
Good luck with it will be watching .
With the 360 movement i was wondering if a fine screw on a geared motor could be used some how for the vertical movement ...i like the mechanical part of this sort of stuff lots of ways to do the same thing ...i only had lego as a boy but i really wanted meccano ! making up for it now :wink:
The electromagnetic spectrum has no theoretical limit at either end. If all the mass/energy in the Universe is considered a 'limit', then that would be the only real theoretical limit to the maximum frequency attainable.
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Re: 0 to 360 degree camera and MORE!

Postby Viewmaster » Mon Aug 29, 2016 5:17 pm

Harry Dalek wrote:With the 360 movement i was wondering if a fine screw on a geared motor could be used some how for the vertical movement ...i like the mechanical part of this sort of stuff lots of ways to do the same thing ...i only had lego as a boy but i really wanted meccano ! making up for it now :wink:


A fine screw would certainly give a smooth movement and one could speed up the motor
to get a fast return to start a new frame.

I think that the nut and screwed shaft would have to swivel in order to
allow for the change in angle as the hinged platform changed angle.

This will also change the line separation slightly, although the Cambridge machine
probably suffers with this too even though it uses a rack and pinion to raise and lower.
(maybe they change motor speed to compensate?)

There is also a rotating mirror possibility but the "Lego look" would go. :)

Yes, Harry, the mechanics is very interesting and challenging too at times.......
......and now PC programing toooooo. :D
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Re: 0 to 360 degree camera and MORE!

Postby Viewmaster » Wed Aug 31, 2016 3:45 am

Just to keep the Lego scanner on this topic and not get mixed up with SSTV.
Latest thoughts on it for anyone.

Instead oscillating the laser back and forth as per Cambridge, it will be fixed.
A small fast spinning rotating mirror, maybe double sided reflective foil, to give twice
the number of scans, will be used to scan the laser beam around.

To vary the picture width from 0 to 360 degrees(!) I will use a sync point
that can be moved around. A small disc with ONE sync hole will travel with the mirror.
When this aligns up with the movable degree opto detector a sync pulse is sent to the PC
to start a fresh line.

Unlike NBTV I don't think that any motor speed variation will be a problem as the
PC program will 'wait' for the start of a new line.....whenever that occurs! :lol:
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Re: 0 to 360 degree camera and MORE!

Postby Viewmaster » Wed Aug 31, 2016 10:25 pm

Harry said...........How about rotating the laser ?

I will explain....in this shelved project using rotating light sensors due to vibration at speed you could use the idea to use laser instead in a simple powering the a rotating laser by induction ,does not have to be a vcr rotary transformer you can make your own simple coils as in the led powered by induction.
Feel free to go you own road on your project just chucking some ideas around if you have trouble with the mirror idea

....................................................
Thanks for your ideas, Harry.
Rotating the laser was my first thought but due to air friction etc its top speed is limited.
I wish to get up into the upper thousands of RPM !!!

I shall mull over your induction idea though. But it looks a bit too techy for this EX gardener. :lol: :lol:

If the laser were horizontally fixed looking at the spinning mirror the true
360 degree, I MUST( :lol: ) obtain would be restricted by the laser body itself.
Angling it up or down results in a curved scan (that might be interesting!!!)

So the laser will be mounted looking DOWN on the very tiny spinning mirror which is facing up
at 45degree on the end of a vertical motor shaft.

In this way only a thin piece of steel holding the laser will obstruct 360 degree scan.
(say just 1/16 inch thick)

I have change my mind (frequently :D ) and will use PWM motors, not stepper.
No need for great motors speed accuracy as the laptop will be slave to scan position.

In the past I have fretted and struggled at times, as many have, to get NBTV motors to sync,
now I am not bothered. Just let 'em wander slightly and I will follow. :roll:
Ah, life of bliss at last! ...........who am I kidding? :lol:
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Re: 0 to 360 degree camera and MORE!

Postby Harry Dalek » Thu Sep 01, 2016 9:16 pm

Viewmaster wrote:Thanks for your ideas, Harry.


Albert will be great to see how your device comes together .

Rotating the laser was my first thought but due to air friction etc its top speed is limited.
I wish to get up into the upper thousands of RPM !!!


Well it is a problem putting any thing on some thing rotating like that as i found out on the vibration problem ...

Are you doing direct drive or a sneaky pulley system getting more speed from your motor /

I shall mull over your induction idea though. But it looks a bit too techy for this EX gardener. :lol: :lol:


Its pretty simple because i can make it :lol: no need if your going mirrors but .

If the laser were horizontally fixed looking at the spinning mirror the true
360 degree, I MUST( :lol: ) obtain would be restricted by the laser body itself.
Angling it up or down results in a curved scan (that might be interesting!!!)


I always run the laser from low till i know the thing works in the direction i want it to and mirrors are a worry ......we are living dangerous ....mine tend to be just a long scan line in one direction yours will be every where .

Thinking you would need around 50mW Green would be the brightest laser point the dot to a wall it will be like a small sun // may be it might be wise to get some laser goggles trouble you need to get the one for each colour your testing so you need 3 if your trying all 3 colours ...know how much you have used lasers Albert but take care /

So the laser will be mounted looking DOWN on the very tiny spinning mirror which is facing up
at 45degree on the end of a vertical motor shaft.


OH yes i see now that will work ~!

In this way only a thin piece of steel holding the laser will obstruct 360 degree scan.
(say just 1/16 inch thick)


are you using plastic mirrors ? they are less dangerous if your to slow getting out of the way of one thats come off at supersonic speed :lol: .

I have change my mind (frequently :D ) and will use PWM motors, not stepper.
No need for great motors speed accuracy as the laptop will be slave to scan position.


Yes at the speeds you need DC will not clog up ! i only found Steppers could be used in manual control slight drifting on the sstv picture scanner and worked fine with the help of pulley system to increase motor speed.

In the past I have fretted and struggled at times, as many have, to get NBTV motors to sync,
now I am not bothered. Just let 'em wander slightly and I will follow. :roll:
Ah, life of bliss at last! ...........who am I kidding? :lol:


The eye is the best sync control yes :shock: i will follow how you do this one theres always more than one way to do something :idea:
The electromagnetic spectrum has no theoretical limit at either end. If all the mass/energy in the Universe is considered a 'limit', then that would be the only real theoretical limit to the maximum frequency attainable.
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Re: 0 to 360 degree camera and MORE!

Postby Viewmaster » Fri Sep 02, 2016 1:59 am

Harry, the spinning mirror is only 1/4 inch diameter so no vibration or risk of bits flying.
I have made a mock up and it works well at this small diameter and at about 5000 RPM

I am well aware of danger with lasers especially as I am spinning its reflection through 360 degrees !
One can have parallel printer cables up to 20 ft long so the scanning will
be done in one room whilst I am on the laptop in another. :lol:

As a few have read this thread it is time to give a warning...........

DANGER
Never look directly at any laser or its reflection in a mirror.
Never shine it in anyone's eyes, including making a cat chase its image on the floor.
Never shine it into the sky, especially when aircraft are around.
“One small step for a man,"......because he has Arthritis.
Albert.
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Re: 0 to 360 degree camera and MORE!

Postby Harry Dalek » Fri Sep 02, 2016 8:22 pm

Hi Albert
Good to see a warning to others ...360 laser line and with vertical scan we are talking a laser will hit your eyes at some point in the scan.
Being in another room is the way to go ...sounds like a good set up i was wondering how you were going to test it .
I rather like lasers so will be interesting to see yours work ... :idea:
The electromagnetic spectrum has no theoretical limit at either end. If all the mass/energy in the Universe is considered a 'limit', then that would be the only real theoretical limit to the maximum frequency attainable.
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Re: 0 to 360 degree camera and MORE!

Postby Viewmaster » Fri Sep 02, 2016 10:51 pm

Harry Dalek wrote:Hi Albert
Good to see a warning to others ...360 laser line and with vertical scan we are talking a laser will hit your eyes at some point in the scan.


Depends on how high up it scans..........one could always stand on a chair. :D

Harry Dalek wrote:Being in another room is the way to go ...sounds like a good set up i was wondering how you were going to test it .
I rather like lasers so will be interesting to see yours work ... :idea:


How am I going to test it you ask, Harry. With fingers crossed and eyes tightly shut. :lol:
(I have ordered laser safety glasses)

Test in stages. First,see if I can continually detect the light changes from the subject under laser scan
especially at top speed now aiming at 20,000 RPM . The reflected laser still looks bright at 5000 at present.

I shall need a multi angle photo diode to test. Maybe a bank of them in a circle?
Any ideas, any one please?

Probably the most critical testing will be the software which has to detect start of each scan and frame.
whilst inputting the light data.

My printer port not only has 8 bit input but I have found out that I can also input on 5 other lines too
so I shall use those for all sync input.

I am working on getting a self adjusting pixel draw time on the laptop to self adjust to any scan/frame times
I set the machine for (all pot adjustable :lol: )


Any sync disk etc mounted on that shaft at of 20,000 could be real trouble.

If a hole were drilled right through the shaft diameter then an opto etc 'looking through' the hole
would get a pulse every 180 degree, so 2 pulses per second.
So I shall drill the hole slightly offset and then only ONE pulse per rev. Neat eh?

Just out of interest, at full speed this is about the pulse time that a NBTV disc gives.
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Re: 0 to 360 degree camera and MORE!

Postby Harry Dalek » Sat Sep 03, 2016 8:57 pm

Viewmaster wrote:
Depends on how high up it scans..........one could always stand on a chair. :D


Good one Albert thats one way of doing it :D

How am I going to test it you ask, Harry. With fingers crossed and eyes tightly shut. :lol:
(I have ordered laser safety glasses)


You can drop your laser light level ,i always run the laser from a very low light level when testing ...you can perhaps put a white screen tube idea around it to see safely and ramp up the laser in the same room just to see how the raster gos ? .

Test in stages. First,see if I can continually detect the light changes from the subject under laser scan
especially at top speed now aiming at 20,000 RPM . The reflected laser still looks bright at 5000 at present.


What are you using as a head amp Albert ?

I shall need a multi angle photo diode to test. Maybe a bank of them in a circle?
Any ideas, any one please?


I found the photo diode transistor very directional and not so good for flying spot idea when i tried it.... even 2 on a crt sstv tracing a picture i had to follow scan line down ,solar cells have a larger surface area but not as sensitive as the trany or diode idea might have to do some testing here
PMTs are as am playing with would be good

Any sync disk etc mounted on that shaft at of 20,000 could be real trouble.
[/quote]

Optical encoder perhaps reflective ?
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Re: 0 to 360 degree camera and MORE!

Postby Viewmaster » Sun Sep 04, 2016 12:10 am

Harry, lowering the laser power is a good idea.

Regarding head amp. I am no good at circuit design as I said so I am
copy and paste (!) a Jeremy Jago design I found in an old Newsletter.

The ADC will probably be an ADC0808, again I have pinched
someone else's brains for the circuit which I now have.........

..........."Thank you, someone else's brains, whoever you are." :lol:

Yes reflective opto encoder but that suggests me out of my shallow depth............again :lol:

I am trying to keep it all with my knowledge boundary.

I am afraid Lego is out now. I am building a more substantial rig for the very high line scan
rates and faster frame rates too. It's a pity but I consider that Lego, even super glued together
will not be up to this task.

Further about testing. I shall enclose the machine in a large tall circular box with various images
around the inside of its diameter. A bit like the inside surface of the old Zeotrope.

Maybe on old beer barrel type enclosure. :roll:

This has the advantages that the laser beam is contained and the photodiode will be
very near and so pick up a big signal.

I built a PMT a few years ago but it has been long scrapped. I might dig it out from the local landfill! :lol:
I have been looking at you excursions into PMT. If one or more diodes don't work then I may have to follow
PMT way. Unlike normal type NBTV cameras, the laser is very bright around the room even at high revs.

There's always higher power lasers, but I don't wish to have to buy a white stick on eBay. :D
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Re: 0 to 360 degree camera and MORE!

Postby Harry Dalek » Sun Sep 04, 2016 12:00 pm

Viewmaster wrote:Harry, lowering the laser power is a good idea.


Running it on low power just enough to see it works for me many a time

Regarding head amp. I am no good at circuit design as I said so I am
copy and paste (!) a Jeremy Jago design I found in an old Newsletter.


Lots of designs out there i just use a ic ...5534 worked well but Steve A mentioned it should be dual powered works very well on single supply so i need to see wha the dual power supply does ...I am no good at it either but swapping op amps with the same power and connection rails you tend to work out which are the best that you have in your junk box if you use a op amp design .

Yes reflective opto encoder but that suggests me out of my shallow depth............again :lol:

[/quote]

Might be good for you one of those things try doesn't work try something else :wink:

I am trying to keep it all with my knowledge boundary.


That is above mine least i don't walk into walks much any way :roll:

I am afraid Lego is out now. I am building a more substantial rig for the very high line scan
rates and faster frame rates too. It's a pity but I consider that Lego, even super glued together
will not be up to this task.


Ideas have to change i call it the reboot most of the time it looks nothing like the start on my projects .

Further about testing. I shall enclose the machine in a large tall circular box with various images
around the inside of its diameter. A bit like the inside surface of the old Zeotrope.


Thats a good idea ,if you have a big old barrel lap shade that might also come in handy to check out things on the laser as in focus line after line how correct it is .

Maybe on old beer barrel type enclosure. :roll:


Yes for sure that would work ...

This has the advantages that the laser beam is contained and the photodiode will be
very near and so pick up a big signal.


You could line the inside wall with a test card or pictures very similar to my SSTV picture scanner but the other way around

I built a PMT a few years ago but it has been long scrapped. I might dig it out from the local landfill! :lol:
I have been looking at you excursions into PMT. If one or more diodes don't work then I may have to follow
PMT way. Unlike normal type NBTV cameras, the laser is very bright around the room even at high revs.


Really depends on the laser power low weak one many be fine for a pmt........... even so you soon loose a lot of laser power in raster lines !

There's always higher power lasers, but I don't wish to have to buy a white stick on eBay. :D


Cheap on ebay but you might have them handy or local yes
The electromagnetic spectrum has no theoretical limit at either end. If all the mass/energy in the Universe is considered a 'limit', then that would be the only real theoretical limit to the maximum frequency attainable.
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Re: 0 to 360 degree camera and MORE!

Postby Viewmaster » Sun Sep 04, 2016 6:23 pm

For anyone wishing to make this machine (fools rush in! :lol: ),
using the rising/lowering hinged platform as Cambridge did and I will too,
there is a linearity problem with line spacing.

I might call it, "The 360 Nip."

Using a rack and pinion to raise and lower means that the descent speed will
start slow, accelerate to its fasted speed when platform is horizontal then slow
down again as it reaches the lowest position (at bottom of the frame.)

Cambridge may have solved this in software but my system will not allow that anyway.

As I am using PWM motor the pot used to control its speed could be moved
VERY SLIGHTLY back and forth by a lever and cam in the motor gearing.
By experiment of length of lever and cam profile one could so vary the motor
speed to compensate. Maybe not perfectly but a slight distortion would
then not be noticeable on the laptop image.

It might be instructive to deliberately wind this pot about as scanning takes place !!
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