May I start a laser harp build thread?

Printable View

10-09-2008, 15:27
Squonk

Laser harp builder's thread!

Hi, all. I am embarking on a project to build a laser harp based on Stephen Hobley's plans. I have all the parts (with one hangup being a Scanpro20 set from Lasershowparts that was DOA) and am eager to start. However, as Bones McCoy might say, "Dammit, Jim, I'm a doctor, not an engineer." I have a laser tech's ambitions with a pediatrician's skill set. :o

So, I'm wondering if I can start a thread here that would accomplish two things:

1. Give everyone else who is trying this a place to share info (Where are you, Jem?)

2. Give me a place to make what I am sure will be many pathetic requests for assistance. (I already have the first one ready to go, but will wait to see if this thread will fly).

Thanks all!
10-09-2008, 16:00
Laseronics

Sounds cool, I dont know who Stephen Hobley is nor have I seen his info.

I do know that Tim Walsh with Laser Speticals has made one in the past. http://www.laserspectacles.com/pages/harp.htm

Plenty of other links on Tims site as well... plus the Jarre site. I saw jarre play the laser harp at a concert in Cairo year 2000, It was truly amazing!

Also, we have a new ILDA member that is making them.
http://www.laserharps.com/
10-09-2008, 23:23
Jem

Hi Squonk

Of course you may start a laser harp thread. It's very nice of you to ask, but you needn't have bothered. If it's got lasers in it it's good to go :D

As we've already discussed, I will be very interested in this and following every step, as you know I already have Steve's instructions and a fair few of the parts, my problem is time, money and motivation ;)

We've not heard from Steve (Hobley) for a while on the forum, but i'm sure he's still around somewhere. Hopefully he'll chime in and be able to offer some advice as well. I would like to know how he's going on with the multi colour harp and the Wii remote :)

May I wish you the best of luck!

Cheers

Jem
10-09-2008, 23:30
soforene

Mebbe our own Carl B (the jammiest git alive, not that I'm bitter) will be able to chip in, having built one himself. ;)
10-09-2008, 23:54
Jem

Quote:

Originally Posted by soforene

Mebbe our own Carl B (the jammiest git alive, not that I'm bitter) will be able to chip in, having built one himself. ;)

Yes, it would be nice for Carl to jump in on this thread and pass on his knowledge. However, the Harp that Squonk and I are talking about is based on Steve Hobleys schematics. This is a *totally* different beast from Carls and I suspect, FAR more complex.

For one, Steve's harp doesn't have any beam termination sensors, and in his latest build you can use a Wii remote to sense the hand position in the beam so that the sound can be modulated by sliding your hand up and down the beam. Also, I believe that he's now built a multi-colour harp so the beam changes from green to whatever colour you like when you stick your hand in it :eek:

All good stuff ;)

Cheers

Jem
10-11-2008, 08:44
Squonk

OK, so here is my first pathetic request for help. As I said earlier, for an electronics engineer, I make a pretty good pediatrician. I'm hung up on the very first stage of the build and hoping someone here can point out my mistake.

I don't want to infringe on Stephen Hobley's intellectual property, but will post this bit of schematic as I think it is pretty generic. It's the circuit designed to take +/- 15V from the galvo power supply and split out +5 and +/- 6 V
http://www.fredettefamily.com/Power.jpg
My problem is that, when I measure across the output of the LM7906 regulator and the common, I get only -0.6V instead of the -6V I want. When I measure the same way at the first two regulators, I get the specified output. I can provide more details if necessary, but would really appreciate any pointers.

Thanks!
10-11-2008, 09:11
ChaosIllumination

Hi,

Looking at that schematic I see that the LM7906 has pins 1, 2 and 3 listed as Vin, GND and Vout, the same as the LM7806.

This may be wrong. LM79XX regulators usually have pins 1, 2 and 3 as GND, Vin and Vout. It's caught me out a few times in the past!

See this data sheet on page 5 as an example:

http://pdf1.alldatasheet.com/datashe...TC/LM7906.html

Hope that helps.

Regards,
Neil
10-11-2008, 09:46
Carl B

Hi Guys

Any thread about Laser Harps then I won't be far away.

My Harp is far more basic than the one that Stephen has built. I would love to move on to the next step and build a frame-less harp if for no other reason than just to make it quicker and simpler to set up.

I have mentioned in another thread that my harp uses light dependent resistors (LDR) as the sensors in a cross frame. When the beam is broken the LDR drops in resistance and triggers a basic Midi controller sending commands to my keyboard.

If there's no objection I'll post some details and photos in this thread on my harp and will be following this thread with great interest.

Just one thing to think about is to use a laser with at least 500mW as getting a sensor to see a beam being reflected of your hand is harder than a beam directly hitting the sensor.

Carl
10-11-2008, 09:52
Carl B

Quote:

Originally Posted by ChaosIllumination

Hi,

Looking at that schematic I see that the LM7906 has pins 1, 2 and 3 listed as Vin, GND and Vout, the same as the LM7806.

This may be wrong. LM79XX regulators usually have pins 1, 2 and 3 as GND, Vin and Vout. It's caught me out a few times in the past!

See this data sheet on page 5 as an example:

http://pdf1.alldatasheet.com/datashe...TC/LM7906.html

Hope that helps.

Regards,
Neil

This caught me out once as well and had the reg go pop in front of me. Not a pleasant smell afterwards.
10-11-2008, 10:17
Jem

Quote:

Originally Posted by Carl B

Just one thing to think about is to use a laser with at least 500mW as getting a sensor to see a beam being reflected of your hand is harder than a beam directly hitting the sensor.

Stephen suggests 100mW to 500mW in his instructions. He actually uses a 250mW 532nm laser in his own personal harp. I think the way he has designed it it is particularly sensitive.

Jem
10-11-2008, 12:39
Squonk

Quote:

Originally Posted by ChaosIllumination

Looking at that schematic I see that the LM7906 has pins 1, 2 and 3 listed as Vin, GND and Vout, the same as the LM7806. This may be wrong.

Thank you, Neil! This completely solved the problem of the -6V output. Unfortunately, though, the +5 and +6 that were working before I rewired the last regulator are now both giving me +3.5 V. I'm hoping that fixing one part of this circuit didn't break the others.
10-11-2008, 13:02
Carl B

I've down loaded the plans for the frame-less laser harp of Stephen's.
Obviously some code is needed for the control of the galvo and the sensor. Is this code part of the downloaded file or do we have to copy it from the .pdf and what equipment is needed to copy the code to the circuit.

Reading though the .pdf it is very obvious that Stephen put a lot of work in to the design for this harp.:eek:

Carl
10-11-2008, 13:12
Squonk

Quote:

Originally Posted by Carl B

I've down loaded the plans for the frame-less laser harp of Stephen's.
Obviously some code is needed for the control of the galvo and the sensor. Is this code part of the downloaded file or do we have to copy it from the .pdf and what equipment is needed to copy the code to the circuit.

Reading though the .pdf it is very obvious that Stephen put a lot of work in to the design for this harp.:eek:

Carl

The pdf plans that you buy include a text document with the Arduino code.
10-12-2008, 09:55
Squonk

Got it sorted. The other problem I was having came from not having the common wire grounded well.

Now on to the second stage. I'm sure I'll be back hat (or soldering iron) in hand soon. ;)
10-26-2008, 07:23
Squonk

Success!

Managed to get through the first part of the harp circuitry this weekend and am now looking at 10 nice green harp strings on my dining room ceiling. I'm sure there are more challenges ahead, but this is really encouraging!
10-26-2008, 09:54
Carl B

Great to hear you are making progress with the harp.

I take it you are driving the scanner with a differential signal. The reason I ask is because I have a spare set of 10k scanners but the signal input is only single ended. If these scanners are up to the job then it seems I have most of the main hardware needed to build a frameless harp.

The big stumbling block for me will be the electronics as I'm OK with basic circuits but beyond that and zero experience with any form of computer code programing I'm a bit stuffed.

Would like to see photo's as we like looking at photo's here on PL, especially of people building projects.

Carl
10-26-2008, 10:12
stanwax

Hey Carl
Im not far away if you need any help with the elecronics side

Rob

PS I will give you a bell later about next weekend
10-26-2008, 10:33
Carl B

Cheers Rob.

When I get round to starting this rebuild of my harp, I'll just be going for the basic Mk1 setup without the Wii remote and will be using my hot 150mW CNI green laser that's doing about 250mW.

I've not read the PDF in full yet but is it possible to assign beams to any note on a keyboard or are they preset to a defined note? The ability to change the note assignment is a must for me.

May be looking at a new project to get finnished ready for UKLEM 4 in Feb.:) And bash everyone's ear's with some J M Jarre again.:D

Carl
10-26-2008, 12:08
Squonk

Quote:

Originally Posted by Carl B

I take it you are driving the scanner with a differential signal. The reason I ask is because I have a spare set of 10k scanners but the signal input is only single ended. If these scanners are up to the job then it seems I have most of the main hardware needed to build a frameless harp.

The big stumbling block for me will be the electronics as I'm OK with basic circuits but beyond that and zero experience with any form of computer code programing I'm a bit stuffed.

Would like to see photo's as we like looking at photo's here on PL, especially of people building projects.
Carl

Hi, Carl. The input to the scanner (one motor from a Scanpro20 set) is S+, S- and ground, so I guess I am using a differential signal. I'm in the same boat with you when it comes to circuitry, though, and might not know what I'm talking about here. Steve Hobley mentioned somewhere on his forum that he thought 10K scanners might be acceptable.

The plans Steve sells come with code for the Arduino, so if you can figure out how to upload it to the chip, you're pretty well set. I'm hoping to modify the code to give me 12 "strings." I think the strings are assignable to just about any note. As you noted, Steve has also modified his harp to use a Wiimote for sensing the position the hand (via the reflected laser light) in space. If I get to the point where I can integrate that, I'm thinking I could use it to tell the harp which octave to play based on how high on the "string" the hand breaks the beam.

Will try to post a pic or two soon, but am a little leery about the amateurishness of my circuit building. :o
10-27-2008, 00:57
Things

10K should be fine, afterall, its only drawing a single line!

And yes, please post pics as you build your project I know I and alot of other people like to watch these things get built :)
11-02-2008, 17:24
Squonk

First light!

So here's the first image of my build. The sensor array and MIDI interface aren't yet attached, but this was enough to keep me entertained for over an hour - just starting and stopping it. As you can see, I have a duplicated string #8. Not sure why. But overall, I'm pretty happy.
http://www.fredettefamily.com/WIP001.jpg
11-25-2008, 19:59
harpbuilder

New framed laser harp posted on u-tube ! ;-)

Hi everyone! i just got signed up to PL, and thought that I would join in here.

I just installed a custom laser framed harp with 8 red 5 mw lasers, in a Children`s Hospital in Virginia Beach VA. ( It is the "Children`s Hospital of the King`s Daughters")
There are five segments of video of it being played on my u-tube page, at customlaserharp. There are also pictures of it on my web site, www.laserharps.com .

I have built three different framed laser harps using both red and green 5mw lasers with photo receptors. I am using a midi controller and software package from OptiMusic, in the UK. Mine is the first laser harp application to use their software. It is capable of registering up to 70 hits ( breaks of the beams) per second, and is fully programmable in both wave files and synth sounds. It can also trigger and control video and image files.

My next project will be to try to design a frameless harp using this same midi system, with low powered green lasers. I want to see if I get them to work by reflecting the lasers back to optic sensors set into the harp body, with different sensors controlling different sounds and such.

Take a look and let me know what you think ! :-) Glenn
11-25-2008, 23:46
soforene

Disappointed you didn't attempt any "Jarre". ;)

Nice work. It would be nicer to see a real harpist trying to play one set up as a real harp though.
Might add "a touch of class".:)
11-26-2008, 05:12
buffo

Hi Glenn! Welcome to PhotonLexicon. Glad you decided to join the forums.

Guys, Glenn has been making custom, closed frame harps for a long time now. He's also done several laser harps, but again, most of them are closed-frame units. The craftsmanship of these instruments is incredible, however. We're talking about a musical instrument that doubles as a beautiful piece of furniture! Of course, the price tag is a bit higher as a result!

I know he's working on a hybrid laser & string design, and he's got some very interesting software that he uses as well. (Will allow non-musical compositions to be played.) Most of his harps are designed to let the general public interact with them (which is why he has so many museums as clients), so saftey is always a concern.

Still, I figured you guys would have fun trading notes (no pun intended) about your harp projects.

Adam
11-26-2008, 08:04
sugeek

Quote:

Originally Posted by buffo

Hi Glenn! Welcome to PhotonLexicon. Glad you decided to join the forums.

Guys, Glenn has been making custom, closed frame harps for a long time now. He's also done several laser harps, but again, most of them are closed-frame units. The craftsmanship of these instruments is incredible, however. We're talking about a musical instrument that doubles as a beautiful piece of furniture! Of course, the price tag is a bit higher as a result!

Adam

Having bought a Non-Laser harp last year, a laser harp seems cheap compared to the cost of a real pedal harp! But to get back on topic, a laser harp project is planned in the future! I was looking at both designs just last night so good timing on this thread! I was actually thinking about using a 1-D MEMS rather than a single axis of a scanner to produce the lense (same difference but just new technology http://www.opusmicro.com.tw/OneDim.htm). What do you guys think of the MEMS, the mirror is quite small which would provide a challenge!

Adam
11-28-2008, 18:02
harpbuilder

Jarre type laser harp in the springtime ! :-)

Quote:

Originally Posted by soforene

Disappointed you didn't attempt any "Jarre". ;)

Nice work. It would be nicer to see a real harpist trying to play one set up as a real harp though.
Might add "a touch of class".:)

Hi Soforene

Glad you like it ! Actually it is hard to get most 'real' harpists interested in this type of harp, since it is not 'real harp' if there no strings attached ! ;-)

Though I do actually have an order for a 36 string electro-acoustic five octave harp with indivual string transducers and stereo out put, that will also have 8 green 5mw lasers installed on the harp. The harpist plays nature orented music, and she will use the green lasers to trigger sampled nature sounds wave files, ( oceam waves, bird songs, etc), and also video and still images of nature, projected via LCD projectors.

The lasers will run along the harp sound baord, just above it`s surface, from treble end down to the bass end, with four on each side of the harp.

This harp will run about $16,000 in price.

Glenn
11-28-2008, 18:10
harpbuilder

Jarre type harp, forgot to explain this ! ;-)

I will be working on a low powered version of the Jarre type harp, with indivual lasers, instead of one high powered one split into many.

They will be 5 to 10 mw pulsed green lasers, that I will be trying to reflect back to the harp body, and I will be directed the beams to various sensors in the surface of the harp. I will also use the filter material that will just let the laser light hit the senors.

I will be able to use a function of the software I use, that alows an analog effect of controlling pitch and /or volume with the amount of laser light reflected to the sensors. This way the height of one`s hand from the lasers, will directly control aspects of thre sound output. The software allow a number of diffrent control functions in this mode.

I will starting to experiment with this type harp in the spring. I also now have a fogger to use when ever I video my laser harps, so the beams will always be seen in the video! ;-)

Glenn
03-01-2009, 09:44
Squonk

So finally got it working this morning. Many, many thanks to Steve Hobley for his unbelievably patient tech support. Hope to post some photos soon, but for now am enjoying watching my kids play with it. The youngest one thinks I'm a genius, when in fact I feel like the D student after all the thrashing about trying to get this working!
03-03-2009, 03:46
Jem

Quote:

Originally Posted by Squonk

So finally got it working this morning. Many, many thanks to Steve Hobley for his unbelievably patient tech support. Hope to post some photos soon, but for now am enjoying watching my kids play with it. The youngest one thinks I'm a genius, when in fact I feel like the D student after all the thrashing about trying to get this working!

Wow, that's fantastic news and I can't wait to see the pictures :)

Did you manage to get it working with the Wii remote?

Cheers

Jem
03-03-2009, 05:12
Squonk

Quote:

Originally Posted by Jem

Wow, that's fantastic news and I can't wait to see the pictures :)

Did you manage to get it working with the Wii remote?

Cheers

Jem

Wii remote is on tap for rev 2...
03-20-2009, 16:53
Squonk

I finished the case today. Here are a few images of v 1.0 of my first laser harp. Thanks to all here who offered advice and encouragement. And if anyone wants to sell a used green laser...

http://www.fredettefamily.com/1.jpg http://www.fredettefamily.com/2.jpg http://www.fredettefamily.com/3.jpg http://www.fredettefamily.com/4.jpg http://www.fredettefamily.com/5.jpg http://www.fredettefamily.com/6.jpg http://www.fredettefamily.com/7.jpg http://www.fredettefamily.com/8.jpg
03-20-2009, 18:50
zerowaitstate

Excellent !
Green stands off the red beautifully, you will have to attach a Mp3 , so we know what it sounds like :)
03-20-2009, 19:58
mikkojay

I'll second the sound/video request- I really like it- good job! It looks almost like sculpture or artwork too+++
-Mike
02-22-2011, 05:10
Master

I think that finally the good harp solution is here at www.laser-harp.com
There you can find commercially available laser harp controller with many advanced features and most important you can hook it up with your existing ILDA laser projector to get green or full color laser harp. All ready to run. Don't have to think about electronic parts or programming in C:) Just plug and play!
02-22-2011, 06:58
lasersbee

Quote:

Originally Posted by Master

I think that finally the good harp solution is here at www.laser-harp.com
There you can find commercially available laser harp controller with many advanced features and most important you can hook it up with your existing ILDA laser projector to get green or full color laser harp. All ready to run. Don't have to think about electronic parts or programming in C:) Just plug and play!

Why are you spamming this forum with that Pro Light Website... :confused:
If you want to sell something... go to the Buy/Sell section..

Jerry

All times are GMT -8. The time now is 00:50.