Pokitto JoyHat

[jonne]

I just calculated it. I would like to keep it <15 eur.

If we drop the rumble motor, it works. The rumble could be optional.

EDIT: the low-volume PCB is also a challenge to cut down from a cost point of view.

Looks like the hat will be between 10-15 EUR. Naturally, if you print your own hat, you can reduce that still.

[jonne]

That translucent case led (pun intended) me to think about a RGB-led. Would it be hard to add?

I think RGB LED’s are surface mount?

[Hanski]

EDIT: the low-volume PCB is also a challenge to cut down from a cost point of view.

When the features are about fixed we could have a poll for pre-orders.

[adekto]

Dumb question but can I request for esp8266 pads on the SPI? I doesn’t have to be populated but it might be handy to have

[jonne]

By using an ebay 2-axis mini joystick breakout, the situation would look like this:

[jonne]

You would like the SPI pins to be brought out? In the JoyHat?

[adekto]

If it’s possible to solder smd on the backside of the pcb could do with the wifi module

[jonne]

I will release the files so you can modify it yourself. PCBway only costs ~25USD for prototypes.

Do you use Diptrace / Kicad / eagle?

Edit: I don’t think I have time / space to fit the ESP module, but you can mod the files to your liking

[adekto]

Have you tried jlcpcb?

[Pharap]

That thumbstick component will cost 5,1 USD per piece.

This is why I say “it depends on what’s available and how much what’s available costs”.

Sourcing parts can be difficult because it needs to be a reliable source
(by which I mean not something that’s going to be there one day and gone the next),
and possibly something that can be bought wholesale.

Perhaps there’s something similar available elsewhere?

If I buy from Adafruit, the cost goes up 2x because of taxes, customs and shipping.

Presumably that means they’d have to be sourced from somewhere in Finland?

the low-volume PCB is also a challenge to cut down from a cost point of view.

Would using an FPGA work out cheaper?
(Just throwing ideas out there.)

By using an ebay 2-axis mini joystick breakout, the situation would look like this

I think that looks like a more manageable size,
but it’s hard to judge when it’s just conceptual.

[adekto]

A way to reduce pcb cost (buy in a larger volume) would be to populated it with as much as as possible and make multiple hats out of one board no?

[FManga]

Version 3 with rumble motor added to top left corner. Its a Jinlong 3V motor, pretty powerful, through-hole with excellent characteristics, but its 2.44 USD a piece!

Since the hat is a disassembled kit, would it be simple to make the motor optional?

It might not work very well if it’s only on one side of the Pokitto, usually a motor is centred

In “upside down” mode, the motor would be in the ideal position in your hands. In landscape mode the vibration would probably be stronger in one hand than the other, but the only way around that is having this and the boots.
Since it isn’t a real force-feedback motor, you can look at cellphones to have an idea of how it would work. You can’t really tell where the motor is inside the phone.

[MLXXXp]

I think RGB LED’s are surface mount?

You can get through-hole ones, as well.

https://www.google.com/search?tbm=isch&q=through+hole+rgb+led&oq=through+hole+rgb+led

Note that through-hole 4 lead RGB LEDs are normally common cathode, whereas with SMD common anode is more popular. So, unless you use a 6 pin SMD part, with individual pins for each LED, switching a design from through-hole to SMD can be difficult in terms of part availability.

[carbonacat]

Looks awesome. Also it solves the local multiplayer issues!

[jonne]

Final design. Next step is PCB routing

BOM

1. Thumb joystick module (PSP style), Ebay
2. 12 mm x 12 mm tactile switches, 2 pieces
3. 6 mm x 6 mm tact switch, right angle
4. 2 x 13 pin 0.1" right angle male header
5. 1 x 4 pin 0.1" right angle male header (I2C local multiplayer)
6. Jinlong 3V vibration motor, 1.7V wake up current, 10k rpm
7. PCB

[adekto]

Could we get a 2x8 female pinout?
Could still have i2c but also serial

[Pharap]

In “upside down” mode, the motor would be in the ideal position in your hands

True, though I think upside-down mode might be a bit awkward because of the amount it extends the Pokitto by.
It would also be hard to use headphones with.

In landscape mode the vibration would probably be stronger in one hand than the other, but the only way around that is having this and the boots.

Or maybe a ‘cape’ that goes all the way along the back of the Pokitto?

Basically imagine another copy of the Pokitto’s back-half,
with a motor stuffed inside and its topside sealed.
Something like that at least.

Since it isn’t a real force-feedback motor, you can look at cellphones to have an idea of how it would work. You can’t really tell where the motor is inside the phone.

I can on my decade-old phone. :P

Seriously though, I don’t have access to a modern smartphone so I don’t know what the vibrate mechanism is like.

[carbonacat]

I might be wrong, but I came under the impression that some of those modern smartphone were using the speakers or something similar instead of motors for vibrations

[Pharap]

I know that some researchers discovered that you can turn a smartphone vibration motor into a speaker,
but I hadn’t heard of a smartphone speaker being used as a vibration motor.

[FManga]

Speaker diaphragms don’t have the necessary mass to vibrate that much.