DSP Robotics Support

I am building a small project that needs to be driven from a sampled float value following a logarithmic waveform pattern. The waveform should follow a spiral similar to the shape of the shell of a snail - I assume that would be logarithmic?? Can this be achieved in flowstone by using primitives or Ruby? Or does such a schematic already exist somewhere which I can use? Much appreciated if someone can help out with this one.

I don't really understand, sorry.

Spiral implies 2 dimensions so if your float value is varying logarithmically and you are sampling it periodically how could you make a 2 dimensional spiral? Is this something to do with a spiral spring Vs force?

Maybe you could sketch out your input and desired output...?

Cheers

Spogg

Hi Spogg, isn't a Sine waveform also two dimensional or do I miss something?

All I need is something that can generate an Float output similar to that of the Mono to Float Primitive, but for a logarithmic waveform not for a Sinewave. I do not need the actual waveform though only the Float output if that is possible?

For example, on another occasion I used the Float output from the M2F primitive to drive a pendulum since that one followed the pattern of a Sinewave. So, the project I am building now is similar in nature it is just that it should be a sampled logarithmic Float output, in other words the float output would increase in a logarithmic manner from 0 degrees to 360 degrees.

I do not have much experience in this field.

regards

In my toolbox, I have 2 PRIMS:

LOGtoLIN and LINtoLOG all FLOAT.

Not sure where they came from, but there are several Toolbox modules from the SM forum that have been saved and re-located to download.

Still ... not sure if this applies. There are also some 're-scaling' modules out there that can translate imputs to a scaled output.

Not sure if this is what you mean but these are spirals from expo envelopes. The shapes on the x-y-scope look like snails to me.

martinvicanek wrote:Not sure if this is what you mean but these are spirals from expo envelopes. The shapes on the x-y-scope look like snails to me.

FFS Martin that's beautiful
You can get so many shapes by changing the waveforms, ADSR settings and tuning.

No idea whether that's what Tiffy wanted but it's great!

Cheers

Spogg

tiffy wrote:Hi Spogg, isn't a Sine waveform also two dimensional or do I miss something?

All I need is something that can generate an Float output similar to that of the Mono to Float Primitive, but for a logarithmic waveform not for a Sinewave. I do not need the actual waveform though only the Float output if that is possible?

What Spogg meant was not the physical dimensions, rather that a waveform evloves in only one direction - forward in time. For a spiral, or a circle, or a square, etc, you would need to go backwards, which can't be done with a waveform. Getting the floats of a spiral should be doable, but it is not a waveform.

EDIT: Imagine you have a pencil and a paper. You put the pencil on the paper far left and start drawing. You are allowed to draw as long as you keep to these two points
1) You only move forward to the right
2) You never drop the pencil (no discontinuity)

That's how a waveform works.

Yes what tulamide said is exactly what I meant

I think what you might mean tiffy is a periodic waveform as a source but not a sine. You could maybe use a triangle as a source and use a transfer function to convert that to the shape you want. Questions need to be asked though. Does the output need to be bipolar, unipolar and at what speed should it run?

Is this closer to your vision?

Cheers

Spogg

martinvicanek wrote:Not sure if this is what you mean but these are spirals from expo envelopes. The shapes on the x-y-scope look like snails to me.

Geez Martin, thank you so much I am going to have a look at it right now.

Thanks to Tulamide & Spogg on enlightening me on the subject and to Mr Hollins.

I will also have a look at what Mr hollins has to offer in his collection.

I had a look on internet on several websites about the Archimedes Spiral and it seems to be much more complicated than I thought it would be.

Thank you all, guys.

Ok, I made a schematic of two equal dimensioned Spiral (Snail) Gears as an example only to demonstrate what the problem is.

These two Gears should mesh with one another fairly accurately if I can get the "Red Spiral Gear" to turn clockwise at the "correct speed" whilst the Black Spiral Gear turns Anti-clockwise @ Constant speed.

There is a description inside the schematic, of the operation of events.

I am not sure how to go about with this one.