Improved stop detection and distance calculation with a speed sensor

Marcel K shared this idea 17 months ago
Collecting votes

Hi!

First of all, Locus is amazing, keep up the great work!


I use Locus to record rides with my road bike and noticed two things:


First, it seems like the total distance of a ride is computed with the recorded gps location points, is that right? If so, I would love to see that the distance is computed from the speed sensor data (with the comulative wheel revolutions parameter and the wheel circumference). This has obvious advantages: The distance will be much more accurate, and the update frequency of the gps points could be reduced without sacrificing accuracy, while saving battery life.


Secondly, I noticed that the stop detection seems to depend on the gps location, correct? If that is the case, one might get an unreliable stop detection if the gps is inaccurate, and a lot of false positives. In my option, it would be a much better solution to use the speed sensor for the stop detection. If the wheel stops spinning, the bike is standing and the activity should be paused. Again this has advantages: It is way more precise than using gps location updates, and thus delivers a more accurate moving average speed.


Again, I really love Locus, but these two improvements would make it the perfect cycling computer for road cyclists, making the accuracy of the track recording competitive with high end dedicated cycling computers!

Comments (7)

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For the second idea: How is the accelerometer sensor is measuring speed? is it based on wind exposure? Also, there is an option in the setting to record only when moving .

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Sure I know that option, but it uses the accelerometer, so it is relatively prone to false positives, I noticed that on my rides. The accelerometer might work okay, but I think if you already own a wheel speed sensor, it is the best possible way to detect movement.

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Oh by the way, if I say speed sensor, I mean something like the wahoo wheel rpm speed sensor (https://de-eu.wahoofitness.com/devices/bike-sensors/bluetooth-speed-sensor), it's a device that you put on your front wheel axle to measure how often it turns. If you know your wheel circumference, you can use it to accurately measure your total cycled distance, and with that your accurate average speed. When only using the gps location points, the total distance tends to be too low and the average speed too high as a result.

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Hi,

I did a comperhensive review of bike sensors and their support and features in majority of bike/sport tracking apps. My findings:

Technically, Locus is than any of these, of course to beat Strava in their "social" features is a challenge. But there are 2 problems , exactly the 2 what what Marcel says:

1. Sensor speed over GPS speed prio:

Also using Wahoo speed sensor, it has ANT+ and BluetoothLE

Once the sensor is connected, the speed measured by the bike sensor should have the priority over GPS speed and should be used to compute ridden distance. (If you use Bike speed sensor, you are obviously on the bike, so you care about how much you have ridden on the bike....). I know you can display both GPS speed and sensor speed, but ATM the distance is computed from GPS speed? Or trackpoint distance? . Sowieso it is not acurate.

2. Autopause. Here I understand there is "track time" and "Track time (movement)" which could do the the trick. However only in case the (movement) is computed exclusively from speed sensor. Otherwise it does show inaccurate information if you use train or something in the middle of the trip... I did not have opportunity to test this yet...

Both of the features (1. speed sensor prio, 2. Autopause based on speed senosor) are implemented correctly in major competitive apps (RideWith GPS, MapMyRide). However for all of these Locus has advantatge: you have profiles. Therefore you are able to set different biking profile for your Mountain bike and different for City bike... So fix the two above and you are the King ;)

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Ok let me describe the desired bike use case (I am frequent biker, using Mountain bike, 2 city bikes and the scooter (kolobezka)). ATM none of the tracking apps can do the scenario completely (shame on you Strava etc..) , but Locus is closest:

1.I put the phone in the rubber holder on my handlebar (with NFC tag), the app detects that this is my Mountain bike, turn on "Mountain bike profile" and start tracking. The profile MTB has specific settings:

a) Autoconnect "Speed sensor MTB" device

b) Autopause (track only movement) - speed sensor based: (tracking is paused/"Track time (movement)" not being measured when the speed sensor does not report any speed > 0)

c) Use "Speed sensor MTB" to compute distance. (Maybe there "Track distance" and "Biking distance" measured separately? )

2. I start biking and ride some distance (eg. 10km)

3. I stop biking and get on the train / bus / mountain lift (eg. 5km) Bike wheel stops turning, sensor reports 0 speed , Movement Time stops being measured. Distance measurement stops (or just new data field "Biking distance" ?), however the track still is still being recorded, to see where I have ridden with the bike/bus/lift.

4. I get off the transport, start biking again, the measurement start again.

5. At the end of the trip I see how much(time, distance) I have ridden on the bike, how much was my ride in total(time, distance).

6. I can use my trips to compute aggregated data such as : how much I have ridden on MTB, City bike, etc...

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Hi,

+1 , same story like Marcel nad Jan . I was using Wahoo , now using Garmin speed sensor. I would love to see a profile where you can measure "biking distance" which is computed only from speed from speed sensor X time.. I do mountain biking , using ski lifts and downhill, if you forget to pause Locus one, the recording of the entire day is useless.. I know many people that use MapMyRide (full of adds) only because of this feature... Please fix it

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Wahoo Bike speed sensor, same problem, please add disstance computed from sensor speed, that matters

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Hi,

I have bought a speed sensor (Magene BLE4 & AT+). I'm very"surprised" that LOCUS does not care, It just show current value, butall the calculations are still from inaccurate GPS . So the sensor is useless . Why?

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Hi Augustin,

Did you properly connect your speed sensor with Locus? Where do you read the speed in Locus? If read the speed from a custom dashboard you have to keep in mind, that there are two different fields for speed:

1. GPS speed

2. Speed from SPD sensor

So if you are reading from a field GPS-Speed that won't change by using and properly connecting the speed sensor. The other speed field will change from 0 to current speed.

Hope that helps.

Best regards

Bernhard

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Hi Bernhard,

Yes ,thats something I'm aware of. I properly see Speed from sensor, I know there are values from both GPS and sensor. But all calculated fields like DISTANCE, MAX SPEED, AVG SPEED are calculated from the GPS speed.

I like to see calculation also from the speed sensor

Also stop detection is using just only GPS speed. If I use train or car during my trip, it will include it in my statistic, making it completly rubbish.

Regards

Augustin

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I used to think my cycle computer/ Odometer was more accurate, but after years of track recordings I now believe the Locus track distance is more accurate. The Odometer depends on the precise wheel circumference/ model of tyre and odo calibration, and whether there are 3 or 4 digits of odo circumference precision.

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It would be possible to add Stop/Start detection based on Bluetooth Sensor data with an locus maps add-on.

Would you like to get one for that? Distance calculation would be based on GPS but only if the wheel is rotating.

If Bluetooth Connection is lost it could stop your recording or it could get into fallback mode where the recording is always on.

For lazy people like me, It would be even possible to add more automation into an addon to do the following things:

- start locus if bluetooth sensor is connected

- start new recording if wheel rotation is detected

- try to connect to bluetooth sensor if locus is open or if locus is recording

- switch settings profile to bike if wheel motion is detected


Just tell me if you are interested in. I may could find some time to create one for this usecase. Because this feature is to special and unlikely to get into locus any time soon. Maybe some time but not soon.