First test run

[sla_newbie]

Hi,

I tried a test run today and faced some difficulties as follows:

1.  I tried to test the setup by piping the Lasershark_stdin_circlemaker.exe to Laseshark_stdin.exe but I get an abnormal movement of the galvos and after a couple of minutes the galvos are starting to heat up.

2.  Also, in the Lasershark_stdin_input_example.txt file, it's given the format of the input is

S=X,Y,A,B,C,INTL_A here the TTL controls are last two parameters but when I try to run input the png file and run the lasershark_stdin_displayimage.exe I get the X,Y,0,0,0,1 the last 3 parameters are same no matter what. Can you me some insight on how to achieve TTL control? the laser is always on and the laser being projected is different.

3. No control for C parameter, when I write the flag -c it says illegal parameter.

I am attaching photos for your reference, thank you

[Macpod]

I do not believe you have been sold 20k galvos. Normally the mirrors on higher-speed galvos are smaller and trimmed at the corners to reduce weight and allow faster speed operation. I suspect these are 10/15K galvos

It is normal for galvos to heat up but not excessively so. Perhaps a better metric to determine if the galvos are being over-driven is the sound. If it sounds bad/scratchy/etc it is

Based on your other post I see you have compiled the lasershark host applications yourself. Have you tried piping in the circlemaker input into lasershark_stdin? This would be a good test to make sure lasershark_stdin has been compiled properly.

 

[Macpod]

I mentioned the kpps rating as I see from your output you are running at a rate of 20,000kpps. For circlemaker that is probably fine but for the displayimage app you may need to reduce that.

1. To start diagnostics, lets focus on the laser on/off state. The laser should be off before you run circlemaker and should turn off after you stop circlemaker. If it is not, something is not wired correctly. Did you solder the provided polarized headers to the LaserShark board and connect wire? Did you verify gnd is going to gnd and the other line is going to +?

2. For diagnostics lets just stick with the circlemaker output. If everything works as expected this should draw a circle. What do you currently see drawn? Have you verified the laser is properly reflecting from one mirror to the other? If it does not draw a circle, what does the output look like?

[sla_newbie]

I have soldered the headers and the wiring is also correct, but I have a concern in my power supply I am using  galvo drivers that takes 15V as input and the laser driver takes 12V input. So is anything wrong with the power supply I am using?

Attaching pictures

Picture 1: Lasershark connection with soldered headers
Picture 2: Galvo drivers (+/- 15V)
Picture 3: 12V laserdriver (+/- 12V)
Picture 4: Power supply units


1. Also when I pipe circlemaker to stdin the mirrors are moving too fast and no image is being projected (Maybe I am overdriving the mirrors like you said. I am looking to replace the galvo setup to 20kpps)

2. Even though I am running the galvos at 20kpps for png file I see no vigorous movement of mirrors(but no movement in Y mirror )and the laser is always ON before operation and even after operation.

I am a newbie to this area and field with no prior knowledge please bear with me and enlighten me.

[Macpod]

I have a concern in my power supply I am using  galvo drivers that takes 15V as input and the laser driver takes 12V input. So is anything wrong with the power supply I am using?

It is perfectly fine to use several voltage supplies of different values (i.e. one 15v supply for the galvos and one 12v supply for the laser diode driver board).

the laser is always ON before operation and even after operation.

The LaserShark pulls A/B/C lines low when the data buffer is empty (i.e. before  and after circlemaker is run). The laser should turn off when the ttl + line is pulled low and turn on when the ttl + line is puled high.
Are you sure the lines between the LaserShark C header and Laser A-13 TTL header are correct? I can't see what colors are going to what pins from the pictures.

1. Also when I pipe circlemaker to stdin the mirrors are moving too fast and no image is being projected (Maybe I am overdriving the mirrors like you said. I am looking to replace the galvo setup to 20kpps)

The LaserShark should still work with your galvos. No need to replace them yet. Just know they won't be as fast. In your application it may not matter.

Does your laser stay on if the ttl pins are plugged in? What image is drawn via the laser if so with circlemaker? I need to see what is being drawn (even if wrong) to diagnose the problem.

Are you using the pre-compiled lasershark_stdin.exe and lasershark_circlemaker.exe for windows?

[sla_newbie]

Hi Macpod,

1. I changed my galvo setup 30kpps, this one has trimmed mirrors and when I piped the circlemaker to stdin I got a circle finally! I think the problem was with the galvo setup and the result is circle can be seen when I connect to B channel and its OFF before and after running it

but not with C channel always ON before and after. Circle is solved!

2. But when I pipe displayimage.exe to stdin.exe only C channel works but the laser is always ON before and after printing. Laser is ON even when I disconnect the C channel with TTL of the Laser module and I feel like no matter what .png file I pipe the laser just sweeps through I get a same trend for all image. How to print a png file are there any specifics?? and can you please provide some little details reagrding the png piping. My purpose is SLA 3D printing. Thank you you're previous post helped me a lot thanks

[Macpod]

Glad you got the galvo part working but I do not think the galvo swap should have been necessary.

Are you using the pre-compiled lasershark_stdin.exe and lasershark_circlemaker.exe for windows? I'm concerned about the B channel working but the C channel not.

If you look at the circlemaker code:
https://github.com/macpod/lasershark_hostapp/blob/master/lasershark_stdin_circlemaker.c
Each line is drawn where A is set to 4095 (max), B is set to 4095 (max), and C is set to 1 (max) This should cause a laser connected to any of these channels to turn on.

Code: [Select]

printf("s=%u,%u,%u,%u,%u,%u\n",
         float_to_lasershark_xy(x_f),  float_to_lasershark_xy(y_f), 4095,4095,1,1); // x, y, a, b, c, intl_a

If you have the lasershark plugged in but not running, what is the voltage between the C channel + and GND pins? (It should be close to if not 0v).
If you pipe circlemaker into lasershark_stdin and probe, what is the voltage between the C channel+ and GND pins? (It should be close to 5v).

I will help you with the lasershark_displayimage debugging after we get this solved. Trying to diagnose displayimage without first resolving circlemaker adds unknowns which makes debugging the overall problem more complex.

[sla_newbie]

1. I was overdriving the galvos I guess because the new galvo setup doesn't make any noise while piping circlemaker with stdin, the old one made a lot of noise and had a tough time reflecting the laser (literally nothing was projected on the screen laser was scattering all over)

2. Yes, I am using the pre-compiled code. One more thing I noticed is that:
--- The Circle is continuous when connected to B channel

--- The circle is broken into 3 segments and not continuous when connected to C channel

3. Yes, the code is perfect and should work just as fine. Let me measure the voltage and diagnose it.

Thank you

[sla_newbie]

Hi Macpod,

I made a rookie error and once I changed the wiring with molex connectors and re-wired it, it works pretty fine. The circle is perfect.

With this thing done I am having issues with the png files. Can you please help me and give specifics on the png file piping methods.

Thanks.

[Macpod]

Hi again, I was out at defcon and wasn't checking this. Glad to hear you found your wiring problem.

For lasershark_stdin_displayimage what is your current problem? The image must be less than or equal to 4096x4096 pixels in size. If you run lasershark_stdin_displayimage with -h help will be printed out

Since you are using a ttl laser you will want to use the monochrome mode. The following will display a png named test.png at 10,000 kpps in monochrome. to use a syntax like

Code: [Select]

lasershark_stdin_displayimage -p test.png -r 10 -m

I would suggest printing a black and white checker board pattern for testing. If you have a smartphone/camera you can use a long-exposure app to get a more complete (and very neat) looking photo

[sla_newbie]

Hi Jeff,

I was busy with other things and started working on this project three days back. Now, it's fine and works like how I wanted.  Thanks.

Now I am wondering to write some python script to loop the process.

[sla_newbie]

Hi all,

I am done with the python code to loop the process, now the code prints the png files that I feed on a continuous loop and now I am looking to improve the code and if possible a GUI.

Thanks