Devo 8: adding a vibration motor

Playing around with the code and the hardware I got the idea to add a vibration motor to my Devo8. The sound is sometimes not loud enough. And the Devo10/7E already have one so I thought the code could easily work for Devo8 also.
Looking at the hardware connections of Devo10 (in the "Articles" section) told me that pin PD2 is used as output. Devo8 does not make use of this pin and I have found nothing connected to it on the board. So I decided to give it a try.
First I wanted to use a simple driver-ic (uln2003) to avoid damage to the mcu when I do something silly. This ic has 7 lines so why not using it for more than PD2? So I looked for some more free gpio pins and found a lot, selecting 7 of them.
Soldering wires to the pins was quite difficult because they are very small (about 0,25mm wide) and there is not many space between them. But with good equipment and a stable hand I got it.
The driver ic gives enough power for a tiny motor. I looked for a little one in my boxes and found a servo where the electronic was dead. The motor seemed to be ideal - small, not much current, working with less than 5V... Cutting a peace of wood, drilling a hole far outside the center and placing it at the motor axis was easy. I simply fastened it with tape at the handhold and tried it directy with the battery - works good, sufficient vibrations to feel them good. Later I will build another weight (surely metal) and place it inside the tx but for now it is good.
Then I soldered the wires correctly (placed a plug in the battery case because I did not want to drill visible holes in the tx case only for testing) - one wire to the output of the driver, the other to VDD (got VDD and GND from an additional header I soldered in the free holes on the left side).
The changes I had to make in the software were really easy: I only had to set the value for "#define HAS_VIBRATING_MOTOR 0" to "1" in target/devo8/target_defs.h. Then opening the tx.ini-file and setting "vibration=1" and I was done!
I have written some easy code to be able to switch vibration off and on without onpening the tx.ini file. I can post it if anybody needs it.
It should work in a similar way in Devo12 but the PD2-pin is used there. So some changes in the code have to be made, but nothing difficult.

I did a backport to deviation-2.1.1, vibrating active for Devo8 and emu_devo8.
I don't know why but I can not attach the .patch-file.
I try a .zip:


And here the full files, also as .zip:

This project is crazy I love it, cudos!

I have placed the actual nightly build (3930f56) for Devo8 with vibration functionality (and in the tx config a place to switch it on or off) in the "build" section .

I like your idea I can't hear the alarm on my radio most of the time either.

I have not had very much to do with electronics such as the innards of a devo8 radio so this may sound noobish.

I gather the MCU is the chip you soldered your single core copper wires to.

Is the output of this chip a voltage that could directly run a tiny vibrating motor like something that's found in a mobile phone or do you need a driver-ic to provide enough power?

On the second picture you can see the MCU left (labeled STM32F103) and the driver ic on the right (uln2003).
The MCU can drive some load (I have looked into the data sheet but I could not find anything about this so I assume the power is quite low). So you will have to place an driver ic or an transistor as amplifier in between - if not you risk to burn the MCU...
I have tested a vibrating motor from a LG phone but the vibrations were too small (the tx is relatively heavy compared to a cell phone) and it was not really remarkable. So I took a motor from a burned servo and soldered some weight to the brass gear.

Righto I get it now.

I have a small vibrating motor that's on my Hobbyking 720P wingcam that doesn't need to be there so I might use it.

What would you use the other connections for that you soldered to the driver-ic?

The driver ic I used has 7 in-/outputs so I looked for unused gpio-pins at the MCU in case of needing them later (maybe for switching between different rf-modules or whatever). The pin I used for the vibrating motor is the same as in the Devo7e/10 so the changes to the software were minimized.
Soldering was really not easy, but when I knew how to solder the first wire the rest was much easier (using a magnifier an a really spiky solder tip and being economical with the solder made it possible).

rbe2012 wrote: Soldering was really not easy, but when I knew how to solder the first wire the rest was much easier (using a magnifier an a really spiky solder tip and being economical with the solder made it possible).

If I can give some advice on precision soldering as is required here - the trick here, and with SMD soldering in general, is to use the solder's capillary effect to limit itself to the pin/pad to be soldered, and not flow all over the place. This is one function of solder paste and the resin inside wire solder.

Thus for these fine pitch soldering, put some solder paste on the pin to be soldered and don't rely only on the resin inside the solder wire. Even better, pre-tin the wire properly and you might not even need additional solder, just heat the wire in place on the pin.

I also like to give my feedback because I have already implemented the idea of rbe2012 some time ago. As a vibration motor, I've taken a servo motor of the 4G6 tail servo, the imbalance is a Main Shaft collar with a screw. I have installed the motor with an old servo holder. Then I took a NPN transistor type BD237, which now controlled via pin 83 (PD2) switching the vibration motor. At last I added a 1N4148 as a free-wheeling diode and a 220 Ohm as a base resistor. It works perfect and I never will miss it again. Thanks to rbe2012.

I have ported the patch to deviation 3.0.0. You can get it from my repo ( rbe2012/deviation-rbe-vibrating ).
The zip-file is placed in the build-section ( see here ).

RCP asked for the wiring. Here you are:

I do not have a Devo8s but I think it will be easier to solder the 220 Ohms base resistor to the spot surrounded by red ....
[EDIT] Photo removed, read the next post ....

Hi domcars0,

sorry, but Pin 83 is an other one

Oh yes I see!! Sorry, so it's not so easy

hI
I would pass my devo tx 8S with deviation and put in a few months the vibrator, can you tell me what versions I have to take?
In advance thanks

Sorry for digging up this topic but ... the current firmware version allows you to install and activate the vibration motor?

Thank you.

If it is a question, I think yes it is supported by the version 4.0.1. If it is not I think by nighties that's OK. Personally, I put the V4.0.1 3b623a8 nighty and that's OK.

saindem, thank you.

Ok, so, would you please describe what need to be made to activate this feature? I need do edit some kind of file?

Cheers!

On the transmitter running the nightly build (this won't work for 4.0.1), edit hardware.ini (do NOT use Notepad on Windows - it's a Unix-formatted file, and you want to preserve that) and delete the semicolon at the start of the line that reads "enable-haptic=1". Make sure you eject the disk before switching the Tx off or out of USB mode.