Hello all, I wanted to share my latest project called PIDflight Lap. It is a video transmitter (VTx) lap timing solution for individual pilots and multi-pilot support for race meets of up to 8 pilots.

It's a simple and easy do-it-yourself build!

Key features:

• Multiple pilot support
  
• Bluetooth (Classic and Low Energy 4.0), Ethernet, WiFi and USB connections supported
  
• Audible announcement of lap times
  
• Multilingual support for English, French, Spanish and many more to follow (Android app only)
  
• Live display of race summary with each pilot's position, best and fastest laps, and total lap time
  
• Cross-platform Chrome app for Windows, Mac OS X and Linux
  
• Easy to use Android app
  

There are two "flavours" of multiple pilot support, and they can be mixed/used together!

1. Dedicated lap timer is where one physical lap timer (i.e. 1x Arduino and 1x RX5808) is dedicated to monitor the signal strength of a single frequency.
   
2. Virtual lap timer is where one physical lap timer is configured to monitor the signal strength of one or more frequencies (experimental firmware currently supports up to 4 virtual timers).
   

I've put together a video to demonstrate the simplicity of the DIY project:


MATERIALS
The basic build requires the following components:

• 1x RX5808 video receiver module with SPI mod (feedback from users is that BangGood are shipping RX5808 pre-modded now)
  
• 1x Arduino Nano
  
• 3x 1K Ohm resistors (recommended)
  

APP: ANDROID

APP: CHROME
     

There is more information available on the website @ https://www.pidflight.com/pidflight-lap/

Please feel free to provide any feedback, suggestions, questions you may have!

Brilliant!!! I have been asking about a cheap and simple timing app for some time, I asked about the option of using video for recognition but the general informed opinion was 'not gonna work'.

Great to see a cheap DIY alternative to the Immersion RC solution that has been 'coming soon' for about 6 months on BG, I will be ordering the parts for this as soon as... I get approval from the Mrs!

really cool! so it needs to stay connected to the phone the whole time to work right? That's how it's powered? Or can it be powered independently?

I think Unseen talked about a timer system that used VTx before but it was more money to buy... or maybe it was the coming-soon one that Tom is talking about I don't remember.

(13-Sep-2017, 10:54 AM)Tom BD Bad Wrote: Brilliant!!! I have been asking about a cheap and simple timing app for some time, I asked about the option of using video for recognition but the general informed opinion was 'not gonna work'.

Great to see a cheap DIY alternative to the Immersion RC solution that has been 'coming soon' for about 6 months on BG, I will be ordering the parts for this as soon as... I get approval from the Mrs!

Cheers! Hahaha good luck! Cooking dinner and cleaning the dishes afterwards always works!

(13-Sep-2017, 05:09 PM)Carl.Vegas Wrote: really cool! so it needs to stay connected to the phone the whole time to work right? That's how it's powered? Or can it be powered independently?

I think Unseen talked about a timer system that used VTx before but it was more money to buy... or maybe it was the coming-soon one that Tom is talking about I don't remember.

Thanks! Yes -- It can be powered by USB OTG (with Android phone) or USB with laptop and serial communication is provided over the USB connection -- OR -- you can extend on this schematic and plug in a Bluetooth module (e.g. HC-06/HC-05 or HM-10) or WiFi Serial module (e.g. ESP-01 or DT-06) on the TX/RX pins of the Arduino. The extended version of the schematic can be viewed @ http://www.pidflight.com/pidflight-lap/build-your-own/

You can then power the Arduino Nano via USB using a USB power brick or XT60 to USB adapter. Alternatively you can power the Arduino Nano directly with a 5v regulator to the Arduino's 5V/GND pins. Power options detailed here -- https://www.pidflight.com/pidflight-lap/...own/#power

Great idea cmengler!

Open hardware design with cheap hardware.
Cheap/minimal cost app.  
Wired and wireless connection.  
Operating system agnostic Chrome app.  

I particularly like that fact that the video receiver is used without an antenna so as to make signal reception really poor and limit reception to the area right at the timing gate.

What's the accuracy like?

Wow, I find this MEGA interesting, great share - THANKS!
Compared to the laptimers I've seen this is super cheap, and seems to work great.
Will be placing an order soon I guess

(14-Sep-2017, 06:55 AM)unseen Wrote: Great idea cmengler!

Open hardware design with cheap hardware.
Cheap/minimal cost app.  
Wired and wireless connection.  
Operating system agnostic Chrome app.  

I particularly like that fact that the video receiver is used without an antenna so as to make signal reception really poor and limit reception to the area right at the timing gate.

What's the accuracy like?

Thank you! I've had great feedback from users already -- the trick is getting an optimal RSSI threshold set (currently a semi-manual process of placing the quad near the timing unit and capturing the current RSSI reading). I'm working on experimental firmware to simplify this so that the RSSI threshold is computed and adjusted with every pass through the timing gate, with the hope of eliminating the calibration process.

I've had users already who have ran it alongside their clubs TBS EventTracker's with feedback that they're getting comparable times are within a +/- 100ms.

I've always wanted to do this since I got hooked by the FPV racing scene. Ironically I'm not that into the racing side of things, but I love watching races! My primary reason I decided to make a start on the project was because I felt there needed to be a more affordable option available for pilots that is portable and easy to use.

(14-Sep-2017, 08:41 AM)Fint Wrote: Wow, I find this MEGA interesting, great share - THANKS!
Compared to the laptimers I've seen this is super cheap, and seems to work great.
Will be placing an order soon I guess

Cheers

(14-Sep-2017, 06:55 AM)unseen Wrote: I particularly like that fact that the video receiver is used without an antenna so as to make signal reception really poor and limit reception to the area right at the timing gate.

What's the accuracy like?

I was wondering if it might be worth wrapping some tin foil over the 'earthed' thread of the sma connector in a kind of 'open oyster shell' shape to further limit the range before and after the gate? I also thought that mounting the RX to the top of the gate, so any one who goes over the top (missing the gate) won't have that lap time recorded in error?

I have ordered the parts from banggood, actually under $10 right now with discounts! Now another 2-3 month wait begins...

Forgot to click post before going and starting the chores, well grass is cut and I should have the dishes done before She gets home, smoked salmon, mascarpone cheese and dill tagliatelle for supper, should negate any moody-ness, but when talking about a wife that's just counting chickens..!

It's hard to say if your oyster shell would have the desired effect, but it's easy enough to try it and see what happens!

Christian, is there any way to use this system with WiFi FPV frequencies? Obviously it would require a different VRX but I am having difficulty finding one 2.4g...

(14-Sep-2017, 11:04 AM)Tom BD Bad Wrote: I was wondering if it might be worth wrapping some tin foil over the 'earthed' thread of the sma connector in a kind of 'open oyster shell' shape to further limit the range before and after the gate? I also thought that mounting the RX to the top of the gate, so any one who goes over the top (missing the gate) won't have that lap time recorded in error?

I have ordered the parts from banggood, actually under $10 right now with discounts! Now another 2-3 month wait begins...

Forgot to click post before going and starting the chores, well grass is cut and I should have the dishes done before She gets home, smoked salmon, mascarpone cheese and dill tagliatelle for supper, should negate any moody-ness, but when talking about a wife that's just counting chickens..!

It's worth a try to see how different shielding techniques may give better results, I haven't had a chance to do any tests with this just yet (wind and rain here now).

Nice, looking forward to seeing your DIY!

Your quite the chef! That should definitely earn points! Hahaha 

(15-Sep-2017, 05:59 AM)Tom BD Bad Wrote: Christian, is there any way to use this system with WiFi FPV frequencies? Obviously it would require a different VRX but I am having difficulty finding one 2.4g...

I haven't looked into this yet -- however if there is a 2.4g VRx module available where the RSSI can be measured then it shouldn't be too difficult.

Quick question, in read that the nano can only offer 40mah to what you connect to it. The receiver pulls way more. Am i missing something?

The 5v rail power source in the schematic is not the arduino, but a separate adaptor. The GPIO pins on the arduino are only used to communicate with the bluetooth module.