Welcome to Multi-Rotor UK. Please login or sign up.

Friday,March 29, 2024, 08:54:07

Login with username, password and session length

Shoutbox

Bad Raven:
26 Mar 2024 08:41:05
 :(
Andy7:
25 Mar 2024 14:49:21
An excess of work and rain.  :thumbdown:
Bad Raven:
23 Mar 2024 18:12:38
Almost a personal Blog, it would seem. LOTS of members, but NO posts.  :-/   :shrug:
Gaza07:
06 Mar 2024 16:59:49
Anyone still here  :shrug:
ched:
24 Dec 2023 11:48:48
Hope you all have a Great Christmas and a happy New Year.
Bad Raven:
20 Dec 2023 06:17:47
 ~~   :beer2: 
Gaza07:
19 Dec 2023 22:20:27
Merry Christmas All  :beer2:
Bad Raven:
01 Dec 2023 06:59:57
New Simulator Section started!   :beer2:
Bad Raven:
17 Jun 2023 06:52:23
Yes, smaller, same as lots of things as time passes.
Andy7:
08 Jun 2023 22:49:18
 ~~
Members
Stats
  • Total Posts: 201,420
  • Total Topics: 20,260
  • Online today: 35
  • Online ever: 530
  • (Tuesday,June 26, 2012, 08:34:46 )
Users Online
Users: 0
Guests: 24
Total: 24

Theme Changer





3d - Printworx

Using a Brushed ESC to dim LED tape

Started by teslahed, Wednesday,November 21, 2012, 23:46:22

Previous topic - Next topic

teslahed

MSlater has made me aware of a new way of controlling LED tape to produce a dimmable effect that can be adjusted from the transmitter by a potentiometer on a spare channel.

Brushed electronic speed controllers work much more simply than brushless ones. They output a Pulse Width Modulated signal on 2 wires (+ / - ) (rather than 3) where the amount of ';on'; time increases as you up the throttle, increasing the average power available to the motor over time. The brushed ESC will take a signal from the receiver on a standard servo lead just as you';d expect, so can be controlled by the throttle or any other channel you want - so assign it to a potentiometer.

LEDs can also be controlled by PWM. As long as the refresh rate is high enough, as you increase the amount of time the pulse is ';off'; for, the eye sees the effect averaged out over time so you perceive the light as dimmer rather than seeing the flicker.



http://www.hobbyking.com/hobbyking/store/__28417__Turnigy_20A_BRUSHED_ESC_UK_Warehouse_.html

The power levels LEDs are running at are low enough that you can probably get away with the lowest current rated brushed ESC you can find. It could be made lighter by removing the heatsink if one is included.

The aim of this mod is to allow the LEDs to be controlled in real time from the transmitter. This means that anyone flying with high density LEDs will be able to reduce their brightness at night so they don';t destroy their night vision and crash. Also i am told that with a suitable computer controlled radio you may be able to program in mixes that make the LEDs pulsate.

I will have to give this a go in the next week or so and report back.

If anyone finds a cheaper and / or lighter brushed ESC i would be interested to hear.


One circlip short of a quadcopter.
 1 lobe short of an antenna.

Gaza07

[url="https://www.youtube.com/channel/UCN6zN99iLCIJea5FCQPKf_g"]YouTube[/url]   [url="https://www.printing-3d.co.uk"]printing-3d[/url]  [url="https://www.thingiverse.com/Gaza07/about"]Thingiverse[/url]  [url="https://www.3d-printworx.co.uk"]3d-printworx[/url]

Balders

I';ve just bought a remote on/off switch funny enough so I can power my leds on and off whilst in flight. I didn';t even think about going this route. thanks Chris!
Growing old is mandatory...Growing up is optional

FPV Guru
BNUC-S qualified
[url="//sbaps.co.uk"]Sbaps.co.uk[/url]

teslahed

#3
Quote from: Balders on Thursday,November 22, 2012, 10:06:17
I';ve just bought a remote on/off switch funny enough so I can power my leds on and off whilst in flight. I didn';t even think about going this route. thanks Chris!

And MSlater! :-D

One idea i have just had which i CAN claim for my own - with my er9x transmitter it should be possible to control the channel for the LED brightness with a potentiometer, but also to mix in (say) 10% from the throttle. This would mean that when you throttled up your LEDs would glow 10% brighter like an afterburner kind of effect. It could look very good and maybe the visual feedback would help with throttle control.

I am not yet sure what mixing options i would use to create a pulsating effect that would vary with time though.
One circlip short of a quadcopter.
 1 lobe short of an antenna.

Balders

Sorry was on mobile and didn';t spot mslater in there. cheers guys!
Growing old is mandatory...Growing up is optional

FPV Guru
BNUC-S qualified
[url="//sbaps.co.uk"]Sbaps.co.uk[/url]

teslahed

I';ve ordered myself one of these from hobbyking UK so hopefully i will get the chance to give it a go in the next few days or so. I';ve tried flying at night a few times recently and the LEDs really are too bright.
One circlip short of a quadcopter.
 1 lobe short of an antenna.

teslahed

#6
I';ve just had a bash at getting this going;

http://youtu.be/B-XPPLxZJ5g

Seems good so far, but i need to get the quadcopter soldered back together now and mix the dimmer in with the computer controlled radio rather than having it attached directly to the throttle channel as i have it now for testing.

[smg id=104]
One circlip short of a quadcopter.
 1 lobe short of an antenna.

Gaza07

[url="https://www.youtube.com/channel/UCN6zN99iLCIJea5FCQPKf_g"]YouTube[/url]   [url="https://www.printing-3d.co.uk"]printing-3d[/url]  [url="https://www.thingiverse.com/Gaza07/about"]Thingiverse[/url]  [url="https://www.3d-printworx.co.uk"]3d-printworx[/url]

teslahed

Now i just need to work out how to do fancy mixing on my er9x so i can get the LEDs to respond 100% to the potentiometer and, say, 30% to the throttle. I presume this is actually possible.

At the moment the LEDs just dim based on the potentiometer.

It should be interesting to see it in the air - the PWM frequency is pretty high but it';s possible you';ll be able to see the refresh rate when i get it moving fast enough - which will either look really cool or really confusing.
One circlip short of a quadcopter.
 1 lobe short of an antenna.

Iberian


teslahed

Quote from: Iberian on Thursday,December 06, 2012, 18:44:31 Just bought this

That looks like it will let you dim the LEDs and produce some nice flashing effect. You need to press buttons on it to get the LEDs to change mode though.

I';ve just managed to mix the throttle from my transmitter in with the potentiometer that i';m using to control the brushed ESC with. Now the brightness varies both with the potentiometer setting and with the power of my motors;

Quadcopter LED dimming test

I';m hoping it will look nice in flight and might even give some visual feedback on throttle settings - not sure if that will help or not really.
One circlip short of a quadcopter.
 1 lobe short of an antenna.

dani_r

Really nice work there :) something to watch for in the future! I have my 500 heli set up for night flight with some custom made night blades etc and it';s VERY bright indeed.