Issues with drag factor calculation after a pause in rowin

[eglin73]

Firstly thanks for all the work in 0.9.6 - I had been using 0.8.3 (I think) and have installed 0.9.6 on a fresh SD card. I have managed to get the Strava integration working, although tbh I preferred the way it appeared in Strava in 0.8.3, I'm glad you decided to keep the integration with Strava rather than scrap it. Thank you.

I have managed to get things working in the new version and things like the Bluetooth connection to my Garmin Fenix does seem to work more smoothly. But I am having an odd issue whereby if I pause rowing for any reason (drink of water for example), then upon starting again things are not so good. I can see on the display and in the logs that the dragfactor calculation, seems to go bad when I pause and restart.

It also stops displaying all metric except metres and time. So pace/500, stroke-rate etc all just stop displaying any data.

I have looked at the logs and can see messages about PAUSE MOVING command and then rowing stopped/paused - and then immediately afterwards the next calculated drag factor is way off (normally around 560, it is now 14000).

I'm not sure where to start on this so have included the log (and my config file) hoping someone has an idea. This behaviour is repeatable.

Thanks
Ian
Uploading ORM 0.9.6 log.pdf…

[JaapvanEkris]

Hi Eglin,

Please realise that your Strava credentials are in the confog you've shared.

I'll dive into the reason why the dragfactor is accepted, as I think it shouldn't accept a recovery with just 3 datapoints.

Jaap

[eglin73]

Hi Jaap,

I'm using a Johnson JAR5100 with 3 magnets and a sensor that I had to add in. I have been using it on 0.8.3 for about 3 years I think with stable results.

My config is in the file, I have added it below too. Most of this, apart from the Strava updates really, I have carried over from the previous version.

Thanks I'll remove the Strava creds

Ian

'use strict'
/*
Open Rowing Monitor, https://github.com/laberning/openrowingmonitor

You can modify this file to configure Open Rowing Monitor to your needs.
This file should be placed in the 'config' folder of Open Rowing Monitor.

All available configuration parameters are visible in config/config.default.js
To modify a parameter, copy it to this file and modify the value.

Changes to this file are persisted when you update to new versions.
*/
// eslint-disable-next-line no-unused-vars
import rowerProfiles from './rowerProfiles.js'

export default{
loglevel: {
default: 'debug',
RowingEngine:'debug'
},

  createRawDataFiles: false,        
  gpioMinimumPulseLength: 100,
  gpioPollingInterval: 5,
  gpioTriggeredFlank: 'Down',
  
  userSettings: {
  weight: 80,
  sex: 'male',
  highlyTrained: true,
  strava: {
  allowUpload: true,
  autoUpload: false,
  clientId: "",
  clientSecret: "",
  refreshToken: "",

},
},

rowerSettings: {
  numOfImpulsesPerRevolution: 3,
  minimumTimeBetweenImpulses: 0.01,
  maximumTimeBetweenImpulses: 0.5,
  dragFactor: 550,
  flywheelInertia: 0.138,
  flanklength:8,
  magicConstant: 2.80,
  numOfPhasesForAveragingScreenData: 4,
  peripheralUpdateInterval: 500,
  autoAdjustDragFactor: true,
  autoAdjustRecoverySlope: true,

},
}

[JaapvanEkris]

Your maximumTimeBetweenImpulses is too long, as this is used to determine the minimum number of datapoints in the recovery. In this setup, a single datapoint will suffice.

Also note, peripheralUpdateInterval is not part of the rower settings.

[eglin73]

Thanks Jaap, I have changed that to 0.2 and initial testing is encouraging, I will do further testing though.

where should I put the peripheralUpdateInterval? (I had added that for use with EXR, although I have now stopped using EXR so could just remove it I suppose?)

[JaapvanEkris]

In the section where you also have the gpio settings etc..

[eglin73]

Ok, thank you Jaap.

…

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