Lego Spike Prime Weather Station with Raspberry Pi -- Episode 543

Great project.

( Now, can you make an input version that allows you to select the weather ?  )

One issue I find though is that these type of projects often tie-up what is often a very limited Lego resource. If you want to keep that weather station, you now have to go replenish your Lego box with the parts you have used, which I suspect could be quite expensive as motors were never the cheapest of Lego parts. Alternatively you view this as the prototype version and then you recreate it with a final build using cheaper components along with 3D printing and then return the Lego parts from the prototype version back to Lego stock for the next project.

With this build, you have hidden most of the Lego look behind the printed cover sheet. Perhaps for true 'LegoLand' style you could use some of the flat shiny tiles (yup the ones that are a nightmare to remove) mosaic stile with stick-on numbers where required.

Yes, I think this fits the prototyping model really well, quick to build up a working model and test the theory and code before buying specific hardware.

As a bonus, I do lots of school sessions as a stem ambassador, and taking this in to the schools has sparked alot of attention from the children.

If only I could use it as a weather input, that would be bliss!

Hi Dave,

Wow - that's really neat! It looks better than real Lego motors : ) Very nice compact design. I take it just the green bit is 3D printed and the plates would be normal Lego as you mentioned earlier.

I think I might bit the bullet and get a 3D printer at some point this year (and just rely on 3D files created by others for now, since I'm still a beginner).

If you don't mind, can I add that image into the motor controller blog post? Just so it doesn't get lost in the comments, that this is how people could use such motors. 

I can't edit the comments : (

I was thinking, perhaps an iteration of it could also have holes on the rear (maybe the other sides too) to accommodate studs for both old and new style technic beams as shown here in yellow and blue. But that may result in a bigger cube if the plastic doesn't have the thickness internally for the studs to fit in, so perhaps it's not worth the effort, since the small cube design is nice and useful as-is.

Yes, the green bit is the 3D printed bit and the red and blue are the standard 4 x 4 plates used to cap it off.

Could potentially get it a bit smaller but at the risk of ending up with non-standard spacings.

Currently it matches the height of 3 normal bricks (or 9 plates).

By rotating the flange by 45 degrees it may be possible to fit it into 3 units wide but not sure if you can get a 4 x 3 plate to cap it with. Could also reduce the height to 2 bricks plus 2 plates, but thought it was easier to start off like this as a proof of concept.

Feel free. I'm already feeling guilty about filling up Katie's project thread here... 

Lots of holes like that can be tricky with FDM 3D printing. What might be easier is to build three sides out of the motor block out of Technic beams and then just 3D print the faceplate for the motor on the fourth side and then trap it between the top and bottom plates. A few dabs of glue if you want to make it a permanent motor block. 

Done, thanks.

This is a really affordable alternative to Lego motors if a 3D printer is available (which probably a lot of schools have by now).

A small laser cutter could be used as an alternative to make it as well. Could cut a load of end panels out of a single sheet to mount the motors on, using castellation top and bottom to knit with the lego bumps for additional strength.  

Perhaps I should just add that the Lego geometry may need to be considered here. If you want to retain positional geometry in height then you would need a stack something like:

   top plate          1/3rd brick high
   spacer plate    1/3rd brick high
   spacer plate    1/3rd brick high
   technic beam  1 brick high
   spacer plate    1/3rd brick high
   spacer plate    1/3rd brick high
   base plate       1/3rd brick high

so one Technic beam in the centre brick position with spacer plates either side.

Ignoring positional geometry, then you could do something like:

   top plate          1/3rd brick high
   technic beam  1 brick high
   spacer plate    1/3rd  brick high
   technic beam  1 brick high
   base plate       1/3rd  brick high

so twice the number of holes but they would no longer align when placed along side 3 technic beams stacked on top of each other.

The alignment of the gearbox shaft with the alignment of the holes may affect some builds. But you could ultimately have multiple 3D models, one of the advantages of making your own motor block. A solution is only a 3D print away...  

SLA 3D resin printing may offer more options here as you could likely print loads of holes and still maintain positional geometry. I'm not sure of the tolerances as they will need to be pretty fine to get the Technic spring pins to lock reliably as they pass through the hole.
(Perhaps avoid using yellow resin, as it could be mistaken for Swiss cheese...) 

Need also to consider where the motor connections would leave the brick. Do you have multiple connectors wired in parallel and flush with the side of the motor cube so you can pick the best side for the project, or do you just pass them through one hole on a flying lead and leave it to the maker of the motor block to decide ?

Perhaps I should just add that the Lego geometry may need to be considered here. If you want to retain positional geometry in height then you would need a stack something like:

   top plate          1/3rd brick high
   spacer plate    1/3rd brick high
   spacer plate    1/3rd brick high
   technic beam  1 brick high
   spacer plate    1/3rd brick high
   spacer plate    1/3rd brick high
   base plate       1/3rd brick high

so one Technic beam in the centre brick position with spacer plates either side.

Ignoring positional geometry, then you could do something like:

   top plate          1/3rd brick high
   technic beam  1 brick high
   spacer plate    1/3rd  brick high
   technic beam  1 brick high
   base plate       1/3rd  brick high

so twice the number of holes but they would no longer align when placed along side 3 technic beams stacked on top of each other.

The alignment of the gearbox shaft with the alignment of the holes may affect some builds. But you could ultimately have multiple 3D models, one of the advantages of making your own motor block. A solution is only a 3D print away...  

SLA 3D resin printing may offer more options here as you could likely print loads of holes and still maintain positional geometry. I'm not sure of the tolerances as they will need to be pretty fine to get the Technic spring pins to lock reliably as they pass through the hole.
(Perhaps avoid using yellow resin, as it could be mistaken for Swiss cheese...) 

Need also to consider where the motor connections would leave the brick. Do you have multiple connectors wired in parallel and flush with the side of the motor cube so you can pick the best side for the project, or do you just pass them through one hole on a flying lead and leave it to the maker of the motor block to decide ?