compatibility with D.Vernooy damping mechanism

[luca-219]

Hi,
I made an openergo and actually I use Dave Vernooy ErgWare (https://dvernooy.github.io/projects/ergware/)
Damping mechanism is made by an optical switch and an light\dark chopper wheel.
I would to try this openrowingmonitor , someone has already tried something silmilar ?

[JaapvanEkris]

We had some OpenErgo machines already, and I recall somebody even playing with an optical sensor. As long as it gives a binary signal when the chopper passes light, it should work.

I do advise you to use V1Beta, as it is better equiped to handle a broader ranges of machines (see https://github.com/laberning/openrowingmonitor/tree/v1beta). In the docs section you find a manual how to set it up: https://github.com/laberning/openrowingmonitor/blob/v1beta/docs/rower_settings.md

[Abasz]

Reed switch is probably the simplest to integrate into hardware. I would go for that.

[JaapvanEkris]

I agree, if you have the option, go for the reed switch (most commercial rowers use this as well).

[luca-219]

in your opinion one magnet on the wheel would be enough?

[Abasz]

If you use more than one magnet they need to be placed very precisely otherwise the rotation Impulse times will be incorrect. So as starter I would use 1 magnet as that is the easiest.

[luca-219]

Hi bought reed switch and magnet. I have a raspeberry 4 model B and monitor.
How I should connect the reed switch in raspeberry?
thank you

[Gordon-Shumway2]

See documentation at
https://laberning.github.io/openrowingmonitor/hardware_setup_WRX700.html

One cable from the switch goes to GND, the other goes to GPIO 17.

Update: sorry, I am not sure whether my answer is correct. Just had a look at other wirings for reed switches using a pi and am now puzzled. Please ignore the answer above for the time being until somebody else answers it.

[luca-219]

ok, I use only this installation and I'll change parameters only after standard installation.

[luca-219]

i set pin 39 as GND and pin 40 as GPIO 21.
I set GPIO21 in /boot/config.txt
gpio=21=pu,ip (reed switch is attached without resistor)

and in /opt/openrowingmonitor/config/config.js

import rowerProfiles from './rowerProfiles.js'
export default {
/*
// example: change the default log level:
loglevel: {
default: 'debug'
},
// example: set a rower profile:
rowerSettings: rowerProfiles.DKNR320
// example: set custom rower settings:
rowerSettings: {
numOfImpulsesPerRevolution: 1,
dragFactor: 0.03,
flywheelInertia: 0.3
}
// example: set a rower profile, but overwrite some settings:
rowerSettings: Object.assign(rowerProfiles.DKNR320, {
autoAdjustDragFactor: true
})
*/
}

gpioPin: 21,

can I test if all work?

[luca-219]

I'm trying reed switch and magnet with drill , but nothing work.
what should I do?

[JaapvanEkris]

The distance seems quite big for me. Could you test with a resistance meter?

[luca-219]

distance is ok, tested with resistance anc circuit switch off to on
I'm not sure about change input from GPIO17 to GPIO21 and cirucit.

[luca-219]

grey cable go to pin 39 and red go to pin 40

[luca-219]

gpioX and gnd count on\off voltage or contact closed is sufficient?

[luca-219]

I should use a circuit like this?

[Abasz]

Pull up is not necessary as Pi has internal settable pull-up: gpio=21=pu,ip the "pu" is the sign that this should be pulled up.

Note GPIO21 is physically 40 not 15.

You can test the circuit with a multi-meter and a magnet. Place the magnet next to the the reed and check visually if the reed actually closes (i.e. a tiny wire should move). then measure the voltage across. it should measure ground (zero). Then move the magnet and measure again, should show approx. 3.3v.

Alternatively, you can check the state of a pin with the following code:
raspi-gpio get 21

you should get GPIO 21: level=1 fsel=0 when no magnet (i.e. HIGH) and GPIO 17: level=0 fsel=0 with magnet (i.e. LOW).

[luca-219]

seems work fine
I send this command while drill si on.
for i in {1..100}; do raspi-gpio get 21 ; date ; sleep 1 ; done
but monitor has -- in all field.

GPIO 21: level=1 fsel=0 func=INPUT pull=UP
Thu 12 Jan 07:58:45 GMT 2023
GPIO 21: level=0 fsel=0 func=INPUT pull=UP
Thu 12 Jan 07:58:46 GMT 2023
GPIO 21: level=1 fsel=0 func=INPUT pull=UP
Thu 12 Jan 07:58:47 GMT 2023
GPIO 21: level=0 fsel=0 func=INPUT pull=UP
Thu 12 Jan 07:58:48 GMT 2023

[luca-219]

[luca-219]

work!!!!

[luca-219]

in config files I have this setting
// command to shutdown the device via the user interface, leave empty to disable this feature
shutdownCommand: 'halt',
where is user interface shutdown button?

[JaapvanEkris]

It is only shown when you call with http://127.0.0.1/?mode=kiosk

So you might need to modify the ip-adress, but then it should work.

[luca-219]

ok, but in this page I lose full screen button.
Can I have both?

[JaapvanEkris]

ok, but in this page I lose full screen button. Can I have both?

I don't think so: the kiosk mode typically runs in a full-screened browser anyway.

[JaapvanEkris]

Perhaps a stupid question, but you have a huge (fly)wheel, why not add the magnet there to the rim? Having so many nicely spaced spokes could even let you add additional magnets if you like.

[luca-219]

yes I'll use that , in my idea i'm going to use 4 magnet, but before I would try all part in my lab rather than in my home gym.