{temporarily note, shift-RC should be updated soon, today as I post this temporarily update I have a working protorype, it is also much simpeler than most of the other designs and uses a cheaper shift chip. more information should follow in the future, just in case anyone watches this know there will be a update soon which simplifies things a lot, makes it cheaper and more relyable and that all while still maintaining the main goal of a small diy budged RC controller which works as a electric micro version of Nikola Tesla's radio controlled boat. ofcource this device doesn't use the exact same technologies, some of them like the radio transmitter and receiver are even illegal in this age n most countries, and the parts aren't mechanical but instead they are electrical/digital this makes it cheap, easy to make, and even more important small and light. again it still works the same in the principle of how it is controlled, it is just a state mashine which on receiving a signal shifts through that state mashine. in the real boat this was done using roller which rotated, around 50 years later when the first commercial rc hit the market it was sometimes done with disks to save cost, but in the end it is basically a state mashine.}
{NOTE, ShiftRC is still heavily in early devellopment, many of the current designs don't yet fully work or only work in very speciffic circumstances. the oldest version does work and is currently the only one which really works and which is stable in use. I am working on making a properly working autoboot. I also forgot to add a stabilization capacitor to the schematics, so if you build any I recommend you to add a 0.1uf capacitor between Vin and Ground. I will update the schematics and documents once I get a prototype to succesfully and relyably autoboot, or a non intusive manual boot. I am sorry for the trouble as of now, I hope to get it to work soon but also often don't know for sure if it is my old breadboard causing problems or a actual thing in the design}
{only the latest versions since 07-03-2022 really work stable in practical applications, some of the older ones do work in speciffic circumstances but they do not work as general rc drivers, read the changelogs and readme files for more information about how they work, problems and how to fix them. not all fixes are added in the designs, and some designs require speciffic use to use them properly, I also discus alternatives sometimes. this file also contains a general changelog which you should read, in the bottom.}
Shift RC is a free open source project.
it has a collection of free open source hardware designs, schematics, documentation, etc. which I made since it could be usefull for some, and can be fun for some people.
The name Shift RC is derrived from the main concept which started it, and that is a digital version of old mechanical state mashine based RC.
for those not knowing what that is, you can look at Nikola Tesla's rc boat which worked in a similar way before there where transistors or tubes.
originally it worked by using spark tubes(coherers), and a motor rotating a mechanism until it triggers the decoherer.
this Shift RC is however a lot simpler, cheaper, smaller, faster, etc. to make and use in the current day. my prototype cost around €0.10 to make, with the amplifiers for stronger output.
the size is really small as well, and I decided to make this project after I wanted to build a very small rc boat and all receivers(with drivers) where much to large for the project.
I also originally wanted it for some fun cheap gatgets since it is much cheaper than even a normal remote module, yet this one also handles the logic.
So if you didn't get how it works yet after hearing it works like the first known RC device, I will explain below
we have a Shift register, which is wired up to loop with itself, the last bit in the shift register is linked to the input.
this makes it a circular device rather than a linear one.
next the inputs are connected in such a way that one signal controlls the entire register updates.
this causes the cyclic shift register to work like a state mashine, every time it gets a signal from IR, radio, sound, or whatever you connect to it, it will go to the next state.
sending a few signals rapidly after eachoter kan make it virtually skip states which allows it to work like a normal remote device.
And as one very important step to make it all work, it has autoboot functionality.
normally a shift register won't really be usable for something like this without adding a microcontroller.
by designing and adding some specialized yet simple hardware, it can autoboot the shift register and make it act like a microcontroller.
this concept also makes the remote a lot simpler, and if you want you can connect a IR receiver and just manually send single IR pulses to go to the next states.
when using something like a Arduino however, you can add quite serious precise controll, this can be done by adding small capacitors to the outputs before the amplifiers.
doing that will allow you to have pwm like controll over everything where the time you keep them on determines the power.
this is something I have designed, but the designs aren't drawn yet.
So in simple words:
you have up to 8 outputs.
for example output 1 does nothing
2 makes it move foreward
3 makes it go backward
4 left
5 right
6 lights
7 turbo
8 force wings
(note these all are just examples you have 8 states, you decide what to connect to it and what your rc thing will do in each state, one state can do many things)
the device starts in state 1.
and every signal/pulse you send it goes to the next one.
this method allows the receiver to be really cheap and small.
and allows the use of ultra simple remotes, or even things like your voice.
when using a good controller, it suddenly can behave like those high end professional controlers
and above all it is open source so you can change it.
OTHER STUFF
with a less advanced shift register things might be more easy. but since this is widely the most used one that makes this speciffic one much cheaper for hobbyists.
you can easly alter the design to your custom shift register like hardware.
just remember:1. single signal register shift, 2. cyclic bitshift, last output is input, 3. autoboot, make it automatically turn on one output.
Changelog
-07-03-2022
time format set to: day, month, year.
Added the first properly working autobooting design, it is in the schematics folder. sort on date. right now it is only 4bit instead of 8 however, but you can use it like 8 bit or even more than 8 bit(for example 12bit) by using some transistor, resistor, diode logic on the outputs, since the delayed clock of the output causes 2 bits to be turned on, it works by checking if any pin is outputing anything, and if it isn't then it will set the signal to serial input high, it however takes 2 clocks to change from input to output so there will be 2 clocks at which all outputs are low, then after that 9 at which atleast one is high. btw, You should stabilize your powersuply by adding a small capacitor between + and -, it is best to add this capacitor as close to the chip as possible to make sure the chip stays working stable since it can suddenly draw more power when switching state due to the cmos in the shift register.
you can use the shift register with only one output on and 8 or 9 states in total(8 bit and off if desired, if not desired remove the resistor and diode from the last output), to use it like this add a small resistor and a capacitor between the srclk(serial clock) and rclk(latch), the values depend on what the maximum input signal would be, so you conect serial clock to the signal then a resistor between serial clock and latch, and a small capacitor between latch and grnd/- this will add a small delay, if large enough it will shift from input to output in only one clock instead of 2. these values of the resistor and capacitor need to be bigger than expected, a extra transitor to rapidly discharge the latch pin when the input signal is low might also be desired. if you have a small ic with smith triggers that will work a lot better, and it will also stabilize the input signal making it perform better against noice. you can look to something like a hex smith trigger or a hex smith trigger inverter, the last one is real common and very cheap, these can be used for delay, but you can also use the other delay method, because the smith triggers make them a lot more stable, I left it out of the designs due to it making it more complex to build, and it would increase parts which might be unneccesary, for example since for people who use of the shelf receiver modules there is a large likelyhood they have something like that in them by default, and then the stabilizing might not be needed, I didn't add the delay for singlephase IO because that has a quite large margin where you might be okay but where it also might just not work, for most people adding a large value there would work well but for some people that won't be good, the discharging of the capacitor might also cause problems if it was not fully charged because the latch might never activate because of that. I might make a properly usable version with a delay and schmitt triggers, I will likely use a IC, but you can make them yourself like this: https://electronics.stackexchange.com/questions/358683/schmitt-trigger-with-three-transistors/611166#611166
-before:
the older stuf.
