nosepokes and other hardware

[Chris Rodgers]

I would like to build a ~30-cm circular arena with about twelve nosepokes and twelve speakers evenly spaced around the circumference. Would it be possible to share the plans for the nosepokes and speaker mounts? They don't seem to be available on the hardware page. (If there's a reason why the plans can't be shared at this time, I will understand.)

I have some experience dealing with CAD files and 3d-printing/circuit-board-printing companies, so perhaps I can help document whatever existing files you have. Let me know if there's anything I can do to help. thanks!!

[jlsaun...@gmail.com]

Certainly -- I'm at pretty reduced capacity between wfh and wildfires, so I can't provide proper documentation for them at the moment, but here is what I have right now:

attached:

- nosepoke.stl - main body of nosepoke
- needle_holder.stl - mounts on back of nosepoke to hold an 18gauge needle for water delivery

- porthole_narrow.stl - mount to hold three nosepokes

- ports_double_v2_annotated-01.png & ports_double_v2.rrb - PCB for three nosepokes driven by ribbon connector. sorry dont have real schematic for this, the .rrb is the file type used by ExpressPCB for designing/ordering. Each circuitboard has two individual boards (split along midline) that I dremel apart
- valve_board.pdf - board used to control valves
- autopilot_default_pinout.pdf - pinout to show connections for basic 3 poke system on a single pi, 24pin connector corresponds to that of the port circuitboard

- autopilot_electronics_bom.xlsx - parts list for basic electronics components

My designs decouple the valve from the nosepoke because they make an audible click which isn't suitable for auditory work. The assembly of the nosepoke is pretty simple, just needs a drill and a soldering iron:

• insert IR beambreak detector (part in bom) and LED into the nosepoke.stl part, if you're using my tripoke PCB you just have to make sure orientation matches the holes in the board.
• stack needle holder on top of beambreak detector with center part facing to the rear.
  
• snap nosepoke into porthole
• solder resistors and ribbon connector onto pcb (see annotated board)
  
• push leads from ir beambreak sensor and LED through board, screw board into place from back through nosepokes, solder points.
• drill hole through needle holder & center of IR-beambreak, dremel tip of 18g needle smooth, poke through hole (holds relatively well w/ friction but can glue if needed).

So I don't have one of those 'exploded parts' diagram but from front to back it goes Nosepoke > Beambreak & LED > Needle Holder > Porthole > PCB.

If you wanted to have independent nosepokes it would be pretty straightfoward, I'd recommend making a breakout board to split out the 3.3v, 5v, and grounds to a few >=7-pin connectors (RJ-type or molex maybe?), you might just take my board and terminate the points for a jack instead of for mounting on back of pokes. I have found having the RGB LEDs in each poke very useful for behavioral shaping -- for signaling active ports/different phases of a task/etc. -- but if you don't need them then you only need 5v, ground and a GPIO pin. The back porthole mounting plate isn't necessary, you can just mount through whatever panel you're using for the arena.

I'm assuming you would want each of the 12 speakers to be independent, which is totally doable. If you want to use the hifiberry amp 2 which I have been using you'll need >=6 Pis, and we'll need to modify the sound server slightly to allow sounds to be played through the left or right channel (shouldnt be hard). Since the agent framework for combining multiple pilots is very freeform i'd be happy to help with writing the task, would also be a good opportunity to think about how that api should work. If you let me know more about the task design I can consult further :)

I can't go to the lab and for some reason can't find pictures of the most recent design, but here are some old pictures that are very similar to the current design (except that the needle holders now mount below the circuitboard rather than above it) -- ignore my shitty soldering and printing, this one was an early draft.

And here is how the valves are rigged, very simple circuit on a prototyping board with some Lee valves & a button for manual opening. Positioned across from a manifold that splits water line -- we have 10 boxes running from a common gravity-fed reservoir that keeps a constant level (same principle as those self-filling pet watering bowls with an upside down water bottle/reservoir) and since each valve needs to be calibrated anyway it's just easier than having a million different reservoirs with variable levels that need to be filled...

[jlsaun...@gmail.com]

Ah, see you also asked about speaker mounts. They're nothing special, using this speaker: https://www.parts-express.com/hivi-rt13we-isodynamic-tweeter--297-421 which is a lovely little tweeter that is very flat between 2kHz and ~40-50kHz without calibration, just mount on the attached fork using the nylon offsets/screws and foam mat (shipped with speaker). Fork slides into mounting stand. When printed with relatively high infill in a tri-hex pattern I get relatively little distortion from the mount. They are angled for the particular size of my arena (to go over the nosepokes to where the mouse would be while poking, so I can figure out how to export & send the fusion 360 design file so you can modify that if you need. Otherwise the design is very straightforward and I'm sure you can cook up what you need :)

[Chris Rodgers]

Ah, how thoughtless of me, I forgot that you are in Oregon. I really hope everything is going okay for you and everyone else out there. 

This is an amazing resource of files, schematics, and designs, thank you so much! It will take me some time to get through, I'll come back with questions and so forth in a week or two.

As a fun puzzle I want to think about some way to drive 12 speakers with only one pi. I think if I make some simplifying assumptions (only one driven at a time? only one type of sound that needs to be triggered?) I can do this in a clever fashion with switching circuitry that will save some money. I'll stew on it for a while. 

thanks!!

[Chris Rodgers]

A few updates on this for future reference:
* I ordered the nosepokes and needle holders from Shapeways, a 3d printing company. I'll report back if the print quality is satisfactory once they arrive. If people want, I can provide a simple link to buy the printed part through shapeways without messing around with the STL files. Could be helpful to decrease barrier to entry to the project, for those without a 3d printer or CAD skills. Just a thought.

* The 18V adapter in the BOM is no longer available, so I got this one instead: https://www.digikey.com/product-detail/en/cui-inc/SDI65-18-U-P6/102-4887-ND/5297506

A few questions:

* I don't fully understand the logic behind the solenoid valve water distribution system. In my previous work, I used a simple 2-port valve (LFAA1209512H) that was normally closed; opening the valve let water flow to the reward port. But the BOM solenoids (LHDA0531115H) are a 3-port design... Where does the 3rd port go to?
* For the RGB LEDs, is it the common-cathode or common-anode version? https://www.amazon.com/Tricolor-Multicolor-Lighting-Electronics-Components/dp/B01C19ENDM

thanks!

[jlsaun...@gmail.com]

Fabulous! yes having shapeways links would be useful. Would also love to hear your feedback on the design itself for a v2, have some improvements already that I would make.

Among the Lee solenoid valves, the LHD series are general-purpose (they didn't have the VHS series when I was putting together the bomb, but they look interesting and i'm going to pick a few up for testing: https://www.theleeco.com/products/electro-fluidic-systems/solenoid-valves/dispensing-valves/vhs-series-solenoid-valves/ ), and within the LHD series the only valves that are ported for direct connection to surgical tubing (rather than needing a specific adapter to plug into) are 3-way. I just put some hot glue in a short length of tubing and made a cap for the normally-open port. The LHDA0531115H is also nice because it only needs 5v which can be sourced from the Pi's 5v rail without needing a step up or additional power supply. Response times are quick and i don't think i've had any fail with almost 2 years of daily operation, ~millions of openings, even without a specific solenoid driver circuit.

I use the CA (sorta by accident to be frank) but either should work -- just need to set the "polarity" flag in the hardware params, polarity=0 inverts logic (so turning "on" makes voltage = 0) so the object can be used normally.

[jlsaun...@gmail.com]

Hmm apparently can't edit posts here? might need to reconsider this tool... anyway bomb -> BOM

[Chris Rodgers]

Re Shapeways: I'll let you know how it looks and if it's good I'll make a link!

Re LEDs: great I'll get CA for compatibility. Seems like the main difference would be what the other end is connected to (5V or G) but maybe I'm thinking about it wrong.

Re Solenoids: That's good to know. I've been using the LFAA1209512H for a couple years now. I don't know why it's not really on The Lee Co webpage but it's in the catalog. https://www.lee.de/wp-content/uploads/2017/04/The-Lee-Company-Electro-Fludic-Systems-Handbook-8th-Edition.pdf

It's ported just like your solenoid, but it's 2 way. Slightly cheaper, but I think a minimum order of 10. It take 12V but looks like they have a 5V version. I might call them and try to find out the cheapest/easiest option.

[Chris Rodgers]

Re Solenoids: I talked to a sales engineer at Lee Co. The LFA series I've been using is going out of stock, so it's not really recommended. That's why the minimum order is 10. The LHD series is the replacement. Sounds like the one you recommended is the cheapest one in that series so there's no money to be saved there. He also recommended plugging one of the outlets just like you do.

I also asked him about the VHS series you're interested in, he mentioned that one is 5x more expensive, so it may be overkill (unless you're doing something really precise, or olfactomer or something).