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Pockit Modular computing demo [video]

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Re: Pockit Modular computing demo [video]

#21

Post by Solder_Man »

varjag wrote: post #20
Solder_Man wrote: post #13

Earlier quoted context omitted.

Only high-bandwidth signal groups (such as HDMI) have the limitation of being usable at only one (or a few) positions. Technically these too can be given more/complete placement freedom, but at the cost of a higher PCB layer count, or exceptional noise-immune routing skill, which I presently don't have. I plan to hire a layout expert to assist with the DFM eventually. The current PCB routing is done such that about 9…

You can't easily splice balanced signal lines, so it's going to end up more complicated than just a routing issue. But I like the concept. I understand that the pads are indexed with magnet locks? What happens if a user crams a component in incorrect orientation anyway?

> signal lines

Good point. I stand corrected.

> orientation

Two features ensure (and encourage) the block placement at the correct orientation.

- layout of the 4 magnets' polarities at each position (and complementary layout on each Block).

- plastic protrusions within the casing (with mating features on each Block).

Just an interesting note: The latter also serve to provide a bi-axial constraint on a Block after attachment, to prevent easy detachment. Together with the (neodymium) magnets, they create a very strong hold, important for Blocks like the Soil moisture sensor demo'ed in this video: https://www.youtube.com/watch?v=vwnpbNNyzdQ&list=UU49EYw900L...

Re: Pockit Modular computing demo [video]

#22

Post by varjag »

Solder_Man wrote: post #21
varjag wrote: post #20

Earlier quoted context omitted.

You can't easily splice balanced signal lines, so it's going to end up more complicated than just a routing issue. But I like the concept. I understand that the pads are indexed with magnet locks? What happens if a user crams a component in incorrect orientation anyway?

> signal lines Good point. I stand corrected. > orientation Two features ensure (and encourage) the block placement at the correct orientation. - layout of the 4 magnets' polarities at each position (and complementary layout on each Block). - plastic protrusions within the casing (with mating features on each Block). Just an interesting note: The latter also serve to provide a bi-axial constraint on a Block after att…

Smart. It's a sweet project, good luck with development!

Re: Pockit Modular computing demo [video]

#24

Post by bogwog »

This is awesome! Seems a little useless/gimmicky at first glance, but the more I think about it the more it makes sense for home automation. It certainly beats buying (or building) tons of specialized devices for individual tasks, and would enable you to solve nearly any task imaginable with relatively little effort.

The limited space for blocks seems like a potential drawback though. Is there a hard limit on the number of modules that you can fit on a single PI? I can't imagine you could just slap on 5 HDMI output blocks on a single board.

Re: Pockit Modular computing demo [video]

#25

Post by moistbar »

bogwog wrote: post #24

This is awesome! Seems a little useless/gimmicky at first glance, but the more I think about it the more it makes sense for home automation. It certainly beats buying (or building) tons of specialized devices for individual tasks, and would enable you to solve nearly any task imaginable with relatively little effort. The limited space for blocks seems like a potential drawback though. Is there a hard limit on the num…

I would assume the number of blocks is limited by the number of available GPIO pins on the Pi, but I can't say for certain.

Re: Pockit Modular computing demo [video]

#26

Post by Solder_Man »

bogwog wrote: post #24

This is awesome! Seems a little useless/gimmicky at first glance, but the more I think about it the more it makes sense for home automation. It certainly beats buying (or building) tons of specialized devices for individual tasks, and would enable you to solve nearly any task imaginable with relatively little effort. The limited space for blocks seems like a potential drawback though. Is there a hard limit on the num…

Glad you changed your mind.

About "limits":

As u/moistbar also pointed out, the number of pins of the Broadcom CPU, and of the STM32 microcontroller, would provide a constraint. If more positions was important, I could easily have put a bunch of IO-expanders or multiplexers.

However, the board was designed with compactness as a priority -- "pocket"-sized and all that -- so as to be portable and flexibly deployable.

The solution for "space" is quite fun: You can chain multiple Pockit boards side by side, through the same style of Bridge-connector that allows expansion to the Display Block in the linked video here.

With this, a huge (but not unlimited) workspace is possible. Frankly, aside from the most spatially demanding application I've tested (a synth/looper setup), I've never needed more than 3 chained together.

> 5 HDMI output blocks I didn't see the need for something like this. There are obviously compromises in every design, and I suppose this is one of them, if you think it's actually valuable. Though an HDMI splitter block would technically solve this issue too.

Re: Pockit Modular computing demo [video]

#27

Post by Solder_Man »

anotheryou wrote: post #23

I know you don't mass produce (yet :)) ?), but do you know how much this would have to cost?

My engineer-mind hesitates to state a number until I finalize the BOM and get tooling quotes, etc. At that point, I'll put up the pricing, etc. on the website and mailing list.

But keeping Pockit's cost down is important in order for the concept to gain a wide community of passionate builders, so just know that I've been and am keeping affordability in mind, starting with even the design choices.

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