Lap Counter via Raspberry Pi

400 views
Skip to first unread message

Mark Erzen

unread,
Aug 6, 2018, 11:13:47 AM8/6/18
to CrossMgrSoftware
I started playing with the $35 Raspberry Pi 


It was immediately useful as a countdown clock for TT's across the local network.  You can either connect a mouse or keyboard to it or remote into it across the network to save you the trouble of keyboard/mouse.  Just connect to x.x.x.x:8765 (ip address of the crossmgr computer) and click on the countdown clock.  The PI comes with Bluetooth, so I output the beeps to my Block Rocker.

For an LED display, it takes a bit more swearing (as Ed put it).

You need: an RGB Matrix Bonnet to drive the LED

An LED display of some sort - Take your pick, but here's a basic one.

The LED's come in different sizes and you can matrix a couple of them together.

Then, you've gotta do in the install guides:
For basic installation of the Bonnet, follow this guide (Note that I suggested getting the Bonnet, not the HAT - the HAT requires all that soldering)

Then, install the LED Matrix software according to the following guide:


To run the stuff, you need to execute the following on the Pi (I still haven't Daemonized it)
  1. sudo ./rpi-fb-matrix matrix.cfg
Then, with the Pi connected to your network, open up a browser to your x.x.x.x:8765 page (might need to use the actual IP address) and click on the lap counter.
You'll see the lap counter light up with the lap number.  Best to adjust background color to pure black and a nice bright color in CrossMgr's Lap Counter screen

Since multiple waves in my races all finish on the same lap, I only display http://x.x.x.x:8765/LapCounter1.html without the race clock.

So far it works pretty well - I need to get it all mounted and figure out how to start everything automagically so that I don't have to remote in (I think I'll have to remote into the Pi for the TT Countdown Clock)


Chris Clague

unread,
Jan 5, 2019, 1:43:43 PM1/5/19
to CrossMgrSoftware
Sounds like a fun project - we were about to attempt something similar. Did you complete yours? and if so do you have any pictures you could share?

mark....@gmail.com

unread,
May 3, 2019, 1:38:24 PM5/3/19
to CrossMgrSoftware


The photo doesn't really do it justice.  There's a bit of a flicker because we're not just sending an 8 and a lap time to the LED display.  We're taking a whole web browser screen and replicating it on the display.  The fact that the Raspberry PI is running the Raspian Desktop and probably has an unnecessary Wifi, Bluetooth, (sound is disabled), and what-not running, we're slowing things down.  Ideally, I'd just run the PI without the UI and have a python program send the lap count and the time through the GPIO to the LED board.  I think I'd have to build something python-ish to get the lap count from CrossMgr across the network and render the number directly to get a really high refresh rate.


But, this lap board is bigger, brighter, and cheaper than any 2-digit LED display I can get from the track and field world, and I don't have to mess around with pushing a button every lap.  


Other alternative was a marine/outdoor monitor - those are becoming more common, but they're still quite expensive.



LAP.JPG

Jonathan Rosen

unread,
May 3, 2019, 1:44:25 PM5/3/19
to crossmgr...@googlegroups.com
LOVE IT!! Do you have a picture of how it was setup at the race? What kind of stand are you using? 

--
You received this message because you are subscribed to the Google Groups "CrossMgrSoftware" group.
To unsubscribe from this group and stop receiving emails from it, send an email to crossmgrsoftwa...@googlegroups.com.
For more options, visit https://groups.google.com/d/optout.

stuart lynne

unread,
May 3, 2019, 2:09:16 PM5/3/19
to crossmgr...@googlegroups.com
I use two 22" LED monitors with a NUC mounted on the back, browser opens the CrossMgr web lap URL. Not waterproof, it is raining we just put them under a tent.

For our weekly crit, we have color-coded bibs and match that on the screen.

image.png
--
__________O___________
_______-\<,____________
_____(_)/_(_)___________
_________________________
Stuart_Lynne____<stuart...@gmail.com>____604-518-1749(m)__604-461-7532(h)

Mark Erzen

unread,
May 4, 2019, 10:12:34 AM5/4/19
to crossmgr...@googlegroups.com


Basically, we rigged up a monitor mount to a lighting clamp and stuck it on a speaker pole 

------------------------------------------------
Mark Erzen
2637 Saint Albans Circle NW
North Canton, OH 44720
(330) 685-5270

Chris Clague

unread,
May 4, 2019, 1:53:46 PM5/4/19
to CrossMgrSoftware
you have more power in your lap board than I have in sign on running RaceDB (raspberry pi)!


On Friday, 3 May 2019 19:09:16 UTC+1, stuart lynne wrote:
I use two 22" LED monitors with a NUC mounted on the back, browser opens the CrossMgr web lap URL. Not waterproof, it is raining we just put them under a tent.

For our weekly crit, we have color-coded bibs and match that on the screen.

image.png

On Fri, May 3, 2019 at 10:44 AM Jonathan Rosen <jonrose...@gmail.com> wrote:
LOVE IT!! Do you have a picture of how it was setup at the race? What kind of stand are you using? 

To unsubscribe from this group and stop receiving emails from it, send an email to crossmgr...@googlegroups.com.

For more options, visit https://groups.google.com/d/optout.

--
You received this message because you are subscribed to the Google Groups "CrossMgrSoftware" group.
To unsubscribe from this group and stop receiving emails from it, send an email to crossmgr...@googlegroups.com.

For more options, visit https://groups.google.com/d/optout.


--
__________O___________
_______-\<,____________
_____(_)/_(_)___________
_________________________
Stuart_Lynne____<stuar...@gmail.com>____604-518-1749(m)__604-461-7532(h)

Jonathan Rosen

unread,
Jun 13, 2019, 10:08:28 AM6/13/19
to CrossMgrSoftware
Mark, what size LED board did you use; 32x32? Would the image be better on a larger panel or a panel with smaller pitch? I've been using a 32" LCD panel but its not visible in daylight. 

Mark Erzen

unread,
Jun 14, 2019, 8:40:42 AM6/14/19
to crossmgr...@googlegroups.com
I'm using 2 64 x 32 panels(Adafruit) chained together in the matrix.    That gives me 64 x 64 total.

I've tried the 64 x 64 panels - but the flicker really increases with those.  To effectively run those panels in a 128 x 128 matrix, you have to shut off the RPi's graphical UI.  Unfortunately if you do that, you can't run the web browser to connect to CrossMgr.

The other choice is a sunlight-viewable monitor (marine quality).  But I think it's a few years before they become practical.  I see more and more of them around in the drive-through windows of McDonald's and other companies - just waiting for economies of scale to make those cheaper.  



On Thu, Jun 13, 2019 at 10:08 AM Jonathan Rosen <jonrose...@gmail.com> wrote:
Mark, what size LED board did you use; 32x32? Would the image be better on a larger panel or a panel with smaller pitch? I've been using a 32" LCD panel but its not visible in daylight. 

--
You received this message because you are subscribed to the Google Groups "CrossMgrSoftware" group.
To unsubscribe from this group and stop receiving emails from it, send an email to crossmgrsoftwa...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/crossmgrsoftware/a2c96a97-d2a3-4bd0-8dc5-a68650de24d3%40googlegroups.com.

For more options, visit https://groups.google.com/d/optout.


--

Mark Erzen

unread,
Jun 14, 2019, 8:41:42 AM6/14/19
to crossmgr...@googlegroups.com
I should point out that a single 32 x 32 will display the lap just fine.  But it's not granular enough to display the lap time

Mark Walling

unread,
Jun 14, 2019, 9:48:22 AM6/14/19
to crossmgr...@googlegroups.com
Inspired by this thread, I built a TT start clock that uses the web socket data available to the start clock web page and draws direct to the frame buffer for the matrix. The code is an utter mess right now, but it proved successful at this week’s TT. I plan on cleaning it up and posting it in the coming weeks, and I plan on making it able to be a lap board too.

Our TTs are ~2 hours before sunset, and the start is facing West, so its kind of optimal conditions for display visibility. That said, from 50’ away I can clearly see the digits. I’m powering the matrix from a 10A buck converter outputting 5V from a 12V SLA battery.

Message has been deleted
Message has been deleted

rkantos

unread,
Jun 18, 2019, 7:26:36 AM6/18/19
to CrossMgrSoftware
Have any of you experimented with e-ink readers with a web browser? I know it has to be a device with an e-ink panel that doesn't refresh the screen every time the content changes. Most E-readers that I know of do this, but I guess this would be unknown with displays which would be gotten from Aliexpress and run with an RPi for example. 
Also, bright displays can quite often be had for cheap. Digital signage has been a thing for quite a while, which means there are plenty of second hand examples of them available. For daylight, you'll probably want something that has brightness of at least 1000 cd/m² brightness. For direct sunlight, it might be necessary to have double or even triple that... That will also mean massive power consumption of something like 400W to 1kW depending on the size :D For comparison a typical monitor will have 250 - 350 cd/m² brightness, and OLEDs and also HDR monitors can have 400 - 600 cd/m². Over 500 cd/m² is probably fine on a cloudy day too, though it might need to have a shade.

Here are some comparisons: https://youtu.be/ejKIk0bLZRg?t=45s 

Mark Erzen

unread,
Oct 6, 2019, 4:49:37 PM10/6/19
to CrossMgrSoftware
Mark Walling,

Just curious if you got anywhere with this.  I"m not clever enough to write the program that reads the web socket directly - so I'm just replicating a Midori page on the Matrix.  Probably to get rid of the slight flicker, I need to read directly and shut off the UI on the rPi.



On Friday, June 14, 2019 at 9:48:22 AM UTC-4, Mark Walling wrote:
Inspired by this thread, I built a TT start clock that uses the web socket data available to the start clock web page and draws direct to the frame buffer for the matrix. The code is an utter mess right now, but it proved successful at this week’s TT. I plan on cleaning it up and posting it in the coming weeks, and I plan on making it able to be a lap board too.

Our TTs are ~2 hours before sunset, and the start is facing West, so its kind of optimal conditions for display visibility. That said, from 50’ away I can clearly see the digits. I’m powering the matrix from a 10A buck converter outputting 5V from a 12V SLA battery.
On Jun 14, 2019, at 8:41 AM, Mark Erzen <mark...@gmail.com> wrote:

I should point out that a single 32 x 32 will display the lap just fine.  But it's not granular enough to display the lap time

On Fri, Jun 14, 2019 at 8:40 AM Mark Erzen <mark...@gmail.com> wrote:
I'm using 2 64 x 32 panels(Adafruit) chained together in the matrix.    That gives me 64 x 64 total.

I've tried the 64 x 64 panels - but the flicker really increases with those.  To effectively run those panels in a 128 x 128 matrix, you have to shut off the RPi's graphical UI.  Unfortunately if you do that, you can't run the web browser to connect to CrossMgr.

The other choice is a sunlight-viewable monitor (marine quality).  But I think it's a few years before they become practical.  I see more and more of them around in the drive-through windows of McDonald's and other companies - just waiting for economies of scale to make those cheaper.  



On Thu, Jun 13, 2019 at 10:08 AM Jonathan Rosen <jonrose...@gmail.com> wrote:
Mark, what size LED board did you use; 32x32? Would the image be better on a larger panel or a panel with smaller pitch? I've been using a 32" LCD panel but its not visible in daylight. 

-- 
You received this message because you are subscribed to the Google Groups "CrossMgrSoftware" group.
To unsubscribe from this group and stop receiving emails from it, send an email to crossmgrsoftware+unsub...@googlegroups.com.


-- 

------------------------------------------------
Mark Erzen
2637 Saint Albans Circle NW
North Canton, OH 44720
(330) 685-5270


-- 

------------------------------------------------
Mark Erzen
2637 Saint Albans Circle NW
North Canton, OH 44720
(330) 685-5270

-- 
You received this message because you are subscribed to the Google Groups "CrossMgrSoftware" group.
To unsubscribe from this group and stop receiving emails from it, send an email to crossmgrsoftware+unsub...@googlegroups.com.

Mark Walling

unread,
Oct 6, 2019, 4:59:26 PM10/6/19
to crossmgr...@googlegroups.com
Well, it ran the start clock for the NYS TT championships, so it kind of proved itself. It’s on my list to clean it up, probably after ‘cross season, but currently its about 8 levels of hack/bodge deep.

To unsubscribe from this group and stop receiving emails from it, send an email to crossmgrsoftwa...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/crossmgrsoftware/5f7fe727-4eb1-42cf-8965-0bfc17e39453%40googlegroups.com.

Reply all
Reply to author
Forward
0 new messages