3D positioning

[Armageddon]

Hi Aerodrums people!

I am new to Aerodrums but an experienced drummer.
First of all, congratulations to the team for developing such a great idea, this is amazing!
But after having passed some time with Aerodrums today, my feeling is the tracking could get better.
There are still flaws and limitations, and to me this is mostly because we are drumming in 2 dimensions.

For exemple, I have a natural tendency to hit my toms with a 45 degrees angle because I have rack toms positioned that way on my real kit. What happens then is Aerodrums do not replicate the whole velocity of my hit as it only records the downward movement, not the forward part of it.
Aerodrums does not take into account my whole movement and all the details of my drumming.

Another exemple is with kit peaces positioning. I have my hi-hat on my left (I'm right handed). Looking from the front, my hi-hat, my first tom and my left crash are not too distant from one another. But that's not the case if you look from the top or from the side: my hi-hat is close to me and my tom is in front of me.
So if I position those drums peaces as on my real kit, they tend to pile on each other in the front 2D Aerodrums space.

I think you all real drummers here will get what I'm saying...

I am then wondering if it could be possible to track the drumming in 3D instead of 2D, especially for the sticks.

It would require maybe a second camera, more processing power and an redesigned algorithm but, man, this would really pass the Aerodrums experience to the 2nd level to me! Far more than the virtual reality features that is under development.

What do you think? Am I crazy?

[bkmsx]

Sounds like you could gain from a mixture of camera height adjustment and then a repositioning of kit pieces, (on copy of default kit say) - the forward distance you refer to is judged by the size change of reflectors as detected by camera. If the cam is quite high looking down then you lose some of that as the size of reflectors remains more or less the same due to the angles.
*Or *because of your habit and hit angles from real playing it could be thatraising the cam a bit and repositioning pieces in Aerodrums may help too! Bit of trial and error and adjusting to your situation I think, but cam height is critical in getting stock kits to play nice.

Best o luck.

[Armageddon]

Thanks for that answer, I did not notice yet any effect of the reflector size change on the playing. I will experiment.
I still believe the 2 dimensions view from 1 camera is a bit limited for kit peaces placement. On real drums you place things around you because from where you sit your reaching aera is an arc. So on the far right and far left, kit peaces tend to get too close to each other in Aerodrums.
Here I will also experiment, I'm not using stock drum kits I made my own for optimum playing performance.

[Richard]

You're not crazy! You make some very good observations. Let me try to address them.

It is true that the "forward" part of the motion is not considered when computing how hard you hit a drum. But the idea here is that you should tune the volume of that drum (and the volume response curve if you want to get fancy) to compensate for this. So if there's a high cymbal that you always hit with mostly forward motion and little downward motion then it's true that repositioning the cymbal so that it's lower down will help give the desired volume response but you could also increase the volume of the cymbal so that it responds the way you expect.

Regarding the tracking, it's not true that Aerodrums only understands the 2D position of the markers, even though this is how it is visualised on the screen. We can infer 3D coordinates of the markers and in fact, if we couldn't do this then doing a 3D/VR visualization of the sticks would be extremely difficult if not impossible. The "forward" motion is not accurate enough for use in computing stick velocity but it is accurate enough for determining which drum was hit, even when their icons overlap on the screen.

You can do this experiment yourself: reposition your snare and hi-hat at different distances from the camera but in such a way that their icons coincide on the screen. You should find that you can still hit the hi-hat and snare reliably...

In spite of this rebuttal, you are correct that Aerodrums could track the 3D position and orientation of the sticks more accurately and this is precisely what we're working on for a future version of Aerodrums.

[BDW430]

What I've noticed is that the forward motion is represented very well in this. Any pieces that are moved forward in real space are represented as above the other kit pieces on the 2d version. I also tend to use a lot of forward whipping motion when going between the bow and bell of my ride and getting a very good response from them. What i would say is try, as Richard said, playing with the sensitivity of it so you do get the same volume response from it. After playing with positioning for a while, I've gotten a very naturally positioned kit set up, even though it may not be represented as such on screen lol. The right side of my kit may look bunched up on screen, but is perfectly positioned in real space.

[Richard]

Thanks for the correction: what I meant to suggest was adjusting the 'sensitivity' slider rather than the volume slider, though you'll probably want to adjust both together.

[Armageddon]

Hey there !

Many thanks for your answers. I did not drum any air for quite a long (too busy pounding on real drum heads).
Good to know how Aerodrums is tracking the "whole drummer's volume". And that's true experimenting with settings, sensitivity, etc... helps a lot.

I did not try to position drums pieces in line with the camera angle, one far and one close. But in real life kit pieces are close to each other. Does Aerodrums perfectly track a few centimetres distance ? I will experiment.

At the end, the solution is obviously not 100% perfect, but really usable. Heaven would come with true 3D positioning, but that would be much more complicated and require more stuff around the drummer. So what do we want ?

Another thing I would like to comment is the lens. In fact, one time the lens got off the camera and I wondered how I had to reposition it : should it be concave or convex ?
Both seem to work in fact.
I even tried without the lens. In that case it works too, but the viewing angle is too small to track everything, especially the feet. The lens function seems to widen the viewing angle in fact.
What I noticed playing aerodrums without the lens is the image is much more defined, and the tracking seemed to be much more accurate.
The lens seems to have a sort of blurry effect. Is that a desired effect to fatten the markers as seen by the camera ?

Having experimenting that, at the end I'm wondering if the tracking on Aerodrums could not improve with a really better camera / lens combination.
Thanks for reading me again.

Now let's whip the air !

[Richard]

Thanks for your comments.

The tracking is very accurate when moving the sticks to the left/right or up/down. The tracking is less accurate when moving the stick towards or away from the camera but it should be accurate enough to discriminate between drums placed close together. We are working on the next version of the Aerodrums hardware which will provide greater tracking accuracy.

The lens is a wide angle lens. It does result in some blurriness but this should not hinder the accuracy of the tracking. While it may seem like Aerodrums behaves well without the lens, a lot of internal numerical factors have been carefully tuned for the lens so we don't recommend altering the intended setup.

[drum4fun]

How about changing the lens by one that has a larger field of view, would this help to accommodate larger drumkits? The default lens I think it covers about 150degrees.

[akramanee]

Hi,
My lens also lens got off the camera. I'm not sure which side now is the original placement. Is the concave or the flat side should be pointing out? Thanks