Positional sensing on megadrum? a dream or a future reality?

[elrules]

Would it be possible to include a routine for "positional sensing" feature for at least the snare head input?

I copy fragments of the new BFD2 sampler coming soon:

The Variable snare articulation allows you to access the hit and half-edge articula-
tions using the positional sensing of snares in electronic drum systems such as those
by Roland.
Positional sensing works by the drum brain sending out a MIDI CC representing the
distance from the centre (where the value is 0) and the edge (value 127).

MIDI CC
Firstly, define a MIDI continuous controller to use as the source for the positional information. Click and drag the MIDI CC value
up and down to set the CC number. You can also define this MIDI CC in the MIDI page Automation view by mapping the relevant
kit-piece slot’s ‘Position’ parameter to the desired MIDI CC.
On Roland kits, this MIDI CC is usually CC #17.

Could it be feasible to implement this feature?

It would be something like:
Enter the manual config in the megadrum for setting the positional sensing on the snare. The module ask you to hit exactly the center of the mesh head. Then, it learns the frequency for at which it is MIDI CC=0. Then it ask you for hitting the edge of the mesh head, and it learns the frequency of the new signal which would be MIDI CC=127. Then when playing it should send MIDI hits for the snare joined to a MIDI CC#17 value.

On this topic you can see how positional sensing works, a photo is included.

With next generation samplers coming in only few weeks it would be fucking amazing to have that feature in our megadrums. I don't know how do you sample the incoming piezo signals. Maybe a PIC with more MHz is needed, I don't know, but I keep saying this feature can be implemented and certainly would be The Feature.

What do you think? Difficult?

[dmitri]

In theory it is possible. At least 2 problems though:
1. Even the fastest AVR might not be fast enough for this
2. It will introduce additional latency of at least one half wave. Is one half wave enough to accurately measure frequency? If not - even more latency will be introduced.

Another MCU? Is there significantly faster MCU, say 60MIPS, but still suitable for DIY, i.e. in DIP packaging?

[elrules]

In theory it is possible. At least 2 problems though:
1. Even the fastest AVR might not be fast enough for this
2. It will introduce additional latency of at least one half wave. Is one half wave enough to accurately measure frequency? If not - even more latency will be introduced.

Another MCU? Is there significantly faster MCU, say 60MIPS, but still suitable for DIY, i.e. in DIP packaging?

I don't know if it is a faster MCU. What I think after reading the patent from roland is that only half wave is necessary to do positional detection. As frequency increases as we tighten the mesh heads, and I like to have them tightened (with roland mesh heads they give better response) it would be less latency. And, if Roland uses positional sensing and its modules have less than 4ms latency, then I think it is possible with megadrum, don't you think?

If would be of help if you explain how you sample the signals to think about a good solution for this

I have just finished Telecommunications Engineering and I am a bit geak of programming. I think I could help with this if you want

[dmitri]

I don't know if it is a faster MCU. What I think after reading the patent from roland is that only half wave is necessary to do positional detection.

If Roland says so than we can disregard latency issue.

As frequency increases as we tighten the mesh heads, and I like to have them tightened (with roland mesh heads they give better response) it would be less latency. And, if Roland uses positional sensing and its modules have less than 4ms latency, then I think it is possible with megadrum, don't you think?

I doubt that they are using a single MCU with only 20MIPS (the fastest AVR) to measure signals in their modules.

I would say if I limit MegaDrum to less inputs, say 8, position sensing would seem to be possible. What is more important in a Drum Trigger - number of inputs or position sensing?

If would be of help if you explain how you sample the signals to think about a good solution for this

I have just finished Telecommunications Engineering and I am a bit geak of programming. I think I could help with this if you want

Thanks! If I struggle with programming I'll ask for help:)

[elrules]

arrrrr, seems it would imply too much work eh?

Maybe having too separate MCU's (one for common entries, and one between analog board and atmega32 calculating midi cc for PS on the snare) it would be possible, and that increases the price of components only a few euros

[dmitri]

If a few euros/bucks/pounds not a problem, than their might be several methods of doing this one of which would be using an additional Digital board with only 8 inputs(4 dual zone pads) connected to position sensible pads.

[elrules]

I hope other people like the initiative. It would be great for using it with FXpansion BFD2 or Native Instruments Battery 3. And saying: "I don't miss any feature of a roland td-20 or td-12, I have them all with Megadrum!"

Could you post your ideas about how to implement this with an additional atmega8 digital board? Would it be difficult to program? Would it be difficult to make it work?

The pads more likely to have articulations for positional sensing are only ride and snare. There are positional sensing sound samples for the snare, I don't know if there are for the ride. At least it only will be necessary for only the snare, but if you say it can manage 4 dual pads.... woooowww, megadrum is great and will be even greater

[estregan]

I think aquawicket's Edrummonitor has features on position dectection. In the future, when Megadrum Controller is integrated with his program, then position detection would be solved.

It may even be possible to do now if you run Megadrum Controller along with Edrum Monitor.

[elrules]

I think aquawicket's Edrummonitor has features on position dectection. In the future, when Megadrum Controller is integrated with his program, then position detection would be solved.

It may even be possible to do now if you run Megadrum Controller along with Edrum Monitor.

How can you do that??? A common mesh head snare pad can only send one signal from the mesh head hits... I can`t think of how to do that with a PC software

[Synthex]

Positional sensing is really very interesting !
I don't think this is so complicated to do it !