DIY remote design inputs

ESK8 Electronics
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In regards to antenna length - you got to check if you are going for 1/2 or 1/4 length and test. I just know that a good 868 mhz antenna (with coils) would be around 6cm. Just something that has to fit in the case :wink:

It`s true that there are plenty of developer boards out there - for a prototype it’s definately sufficient - I just like to make it into something clean in the end. But as it is with most prototypes - they stay like they are right? :wink: - so I started designing them from the start already into the direction haha

Ah I get why the 18650 - I honestly wouldn’t worry so much about pricing for a battery. (lipo is 3-4 euros) - if it is easier to fit things into a case. I do get what you mean with your palms - I have rather normal hands and thus 2cm is the max that feels comfortable for me.

Anyhow - if you like and want - we can have further discussion and share our results - and/or work together on a prototype.

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I dont think the antenna atleast should be the reason to go ghz :wink:

You are so right there sir ! If it works… why use time perfecting it… thoe… it feels great to have a finished product like yoours :wink:

My current remote: https://www.aliexpress.com/item/F01719-3-Flysky-FS-GT3B-2-4G-3CH-Gun-Transmitter-Receiver-RC-Car-Boat-FS-GT3B/32339629939.html

Is way thicker… it lays great in the hand… but I think 20mm is where it goes from nice laying in the pocket all day… to 25mm where it felt awefull (atleast with my first prototype design print) (do you have access to a 3d printer ? could send a stl file, then you could try to feel it in your hand) Maybe I change to flat lithium cells, the 18650 is just the start :slight_smile: I just like the cell I think :blush:

I would love to work with you ! Whats your geographic location on this planet ? Mine is Denmark

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Seems as if RFM69 is the new player intown… it can be 433-868-915Mhz, så plenty of options, for about 2£ only :smiley:

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I have access to a 3d printer at a fablab closeby - but unfortunately don`t own one myself :cry:

Don`t feel obliged to change anything - I like to bounce of ideas and discuss them - sometimes I have an idea and I don’t realize it’s actually not good/feasible until some tells me :wink:

Yes the RFM69HCW modules are great - they have quite robust protocol already - and they offer hardware encryption with aes128 (that should be sufficient to not be harmed by someone/something just poking around :wink: )

There is a development board called “moteino” with a really great forum - there is a lot of information in regard to that developer board an to rfm68 modules in general.

I am from the south of Germany - so not to far apart ;-). btw I just noticed that we started talking about vesc (and vesc 6.0) beforehand :flushed: - didn`t realize it until now.

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14455858_10154734199214095_1227732993_o.jpg1080×1701 85 KB

Version 4 of the case :smiley:

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This topic is really interesting and fun to read! Keep it up! :smiley:

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1475009092523-1931160101.jpg3120×4160 2.36 MB

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I will keep it running, until the remote is a working finished device :smiley: maybe others want one at that time :smile:

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Fablabs are great ! but if you one day get the possibility, buy one, especially if you like designing custom electronics… its awesome to make the perfect casing for your projects :smiley: (wall mounted tablets, rc remotes, custom fan for motors, battery compartment for esk8-boards)

just keep the ideas flowing, I will if possible try to incorporate the ones I can apply :smiley:

The RFM manufacturer are really good, also when it comes to documentation, eventhough they gave me a hardtime in 2011 trying to get rfm12’s to work :stuck_out_tongue:

Awesome ! I will give the forum a look later in the project then :smiley:

South of Germany, south of Denmark, awesome ! :smiley:

I know :wink: and the VESC assembly is most properly starting within two weeks :slight_smile:

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Dear i have a question for you. I recently lose my remote control for my electric skateboard 800w zles. And i cant find the same. I buy a new one with the reciver buy the plug has 3 cables and the reciver of my board has 4 white cables. And u dont know how to pair it. I can pair the newcontrol with the old reciver? I have to change the reciver? I send you some pics for you to see. If you can help me i really apreciete because in my country no body knows so much for electric skateboards.

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I had a quick look for small size antennas:

I found a couple of helical antennas for cheap on aliexpress

I guess it would be best if we can fit the antenna (16 - 30mm) in the upper part of the casing - next to the speed throttle?

During my search for a throttle I was actually planing to use a joystick potentiometer and either just guide the axis of the throttle to be solely y bound. Or take it apart and create a different mount.

Another option would be to go down the hall sensor route (similar to boosted board remote

I unfortunately haven`t had much to do with electronics (in form of communication technology) to asses if the magnets however would interfere with the antenna - will ask some people who actually studied that to see if they have any remarks.

Do you have some measurements of the case for me? Then I would start with designing a PCB in the next weeks

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I would try to contact the manufacture, as 4 white cables dosnt tell much :frowning:

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I think at least that the antenna is best suited with being in the top, outside the hand, else you could interfer… The small joystick or potentiometer ideas are really good, but I think hall effect is the simplest and smallest footprint to build It shouldnt interfer, aslong as the halleffect sensor is sub-mhz, and the antenna is mid-high Mhz range :slight_smile:

Which ECAD software are you using ? Can it import step og DXF files ?

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I am not yet completely sure about the hall sensor as throttle - have no experience with using a hell sensor so far. And any design implications that a setup like this requires. I am just hesitant in regards to any interference - also in relation to the hall sensor. Probably will order some sensors and test/play around with them to see how they behave and react :wink:

I am using Cadsoft Eagle - it is actually the one ECAD I`ve grown up with and am by now the most comfortable. It seems that it supports dxf imports but I haven’t used them yet :wink:

Maybe it is time to move to a different ECAD software - heared great things about KiCad?

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Try to order some S49E, they are pretty cheap on ebay, and works down to 3V, and are NOT a hall effect switch ;D

Actually I havent used anything else than Altium, mainly due to me line of work :wink:

But KiCad seems really awesome! I’ll try to export some DXF of a cut section, then you know the envelope of your board, if you want the same shape, that is :wink:

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I was looking at Hall Sensors from AllegroMicro to already deal with the behavior of SMD versions

The general shape is great - just don’t know how you feel about a “dead mans switch”? Different question in that regard: would there be enough space in the upper part to place the RF69HCW module (16x16mm) and the antenna?

There is no need to rush the DXF files - I’ll probably don’t get around doing the pcb layout before early october.

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the link was broken :frowning: http://www.allegromicro.com/en/Products/Magnetic-Digital-Position-Sensor-ICs/Hall-Effect-Unipolar-Switches/A1120-1-2-5.aspx

If you run the pcb under, then smd is the way to go :wink:

I’am planning to design a trigger switch, for the index-finger, but should I do ON/Off or analog switch ?

See this picture, its the RFM12 module, but I think its the same factor, as this also is 16x16

side_view_open.PNG474×793 141 KB
But We’ll just change the shape to the parts and back :slight_smile:

The following is only preliminary design… but the basic shape is defined :slight_smile: DXF and PDF file: http://www.fileconvoy.com/dfl.php?id=gd0da7c288b53d0189998803219660930ca3687026

And this drawing is at the center, of the remote

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Going to post a couple of thoughts and findings :wink:

If we have the throttle at the thumb, I think a ON/OFF switch for the index-finger (as trigger / dead man`s switch) is suffice. Will keep the design simpler and I don’t see any usage scenario for also doing this part analog (i.e. with a hall sensor).

Some thoughts on the thumbwheel:

  • For the hall sensor to be more precise, allego micro propose a push-pull combination. That would require having 2 magnets and the hall sensor would need to be inbetween those two
  • I propose to make the thumbwheel “more solid” - as I think the “dust guard” might break easily. Also this would provide more space for magnet configurations - what do you think?
  • What mechanism do you propose to have the thumb return to neutral? (I was thinking that the thumbwheel is similar to the wii controler, that the movement is for acceleration/deceleration - or do you see it differently?)

I’ve tried to inform myself a bit more on antenna designs and the RFM module and found some interesting notes

On page 7:

When the coil runs near and parallel to ground, maximum gain is only -18 dBd. When the loose end of the coil was pulled away from ground, as shown in the alternate version drawing, gain increased to -5.5 dBd, and the null became deeper.

and

The big problem with this antenna is the mechanical construction and it’s bulky size. It can be easily de-tuned by nearby objects, including a hand, so it may not be good for hand-held use.

So I wonder if it would be good to keep the current space of the RFM module just for the antenna and move it further down? Also the note on the application with a hand nearby worries me slightly :frowning:

On a different note - since you switched to lipos, wouldn’t it make sense to also move the OLED display closer to the bottom in order to not overlap with the center point of the thumbwheel?

On the topic in relation to communication, I’ve found a couple of interesting products/implementations. Most interestingly was OpenLRS. An open source RC implementation using 433 / 868 / 916 mhz modules, offering encryption, frequency hopping and other interesting features. It has been widely used by a lot of people for drones/rc planes. When I find the time, I will evaluate this firmware and see if/how it could be used for our remote. As far as I could tell though, it offers quite a lot of features (including telemetry).

There are also “commercial” OpenLRS products based on Atmega328P (example, example 2) available.

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I will reply more thoroughly later… but for now take a look on this guys design

https://www.radicalcreation.com/forums/viewtopic.php?f=6&t=35&sid=1657148f8f9f4948887332cdcd84c904

thats my inspiration for the thumb controll, push pull and return, everything is shown in his videos :slight_smile:

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You really did some research here ! :smiley: like it ! I dont think you should be so worried about the hand at the antenne, remember these devices are used for ranges upto 0,5km … we “only” need 2-10 meters :slight_smile: I actually think… if we dont give a f… about the PA stage in the module, we could do it with out antennas on :stuck_out_tongue:

That stack, or what its called… openLRS, is really awesome ! but is it maybe over complicating the software ? I mean, I want encryption, and telemetry, but if the code still needs to be edited by the users, arduino ide ?.. then a simpler setup could maybe do the stuff

What do you think ?