[Help Wanted]: useKalman: true causes odometer to stay at 0.0 — correct config to reduce stationary GPS jitter on odometer? #1660
Description
Required Reading
- Confirmed
Plugin Version
5.0.5
Mobile operating-system(s)
- iOS
- Android
Device Manufacturer(s) and Model(s)
Samsung A36, iPhone 17 pro, iPhone 13, Honor 8 lite
Device operating-systems(s)
Android 15, IOS 26.3
What do you require assistance about?
We recently migrated from v4 to v5 (5.0.5). After extensive testing, we found that useKalman: true causes
location.odometer to always return 0.0, regardless of actual movement.
Our goal: Reduce GPS jitter accumulation on the odometer when the device is stationary. During a 20-minute stationary period, the odometer accumulated ~70m of false distance due to GPS drift, even with good accuracy readings (6-8m).
What we tested (5 tests on Samsung A36, Android 15):
| Test | useKalman | odometerUseKalmanFilter | maxImpliedSpeed | Odometer | Tracking |
|---|---|---|---|---|---|
| 1 | not set (default true) | not set (default true) | not set | 0.0 always | Poor (12 points in 6h) |
| 2 | false (explicit) | false (explicit) | not set | 0.0 always | Better (22 points) |
| 3 | false | false | not set | Working | Working |
| 4 | true | false | 60.0 | 0.0 always | Degraded |
| 5 | false | true | 60.0 | Working | Working |
Key findings:
- useKalman: true breaks location.odometer completely (always 0.0), even when odometerUseKalmanFilter: false
- odometerUseKalmanFilter: true works correctly when useKalman: false
- Tests 1 and 2 both had odometer=0 because v5 defaults useKalman to true — we initially didn't realize omitting theparameter meant Kalman was still active
Our questions:
- Is useKalman: true expected to affect location.odometer even when odometerUseKalmanFilter is set independently?The documentation says they are independent Kalman instances.
- What is the recommended configuration to minimize stationary GPS jitter on odometer while keeping accurate tracking? Specifically, is there a way to prevent odometer accumulation when isMoving: false?
- Is this a bug in 5.0.5 that useKalman: true zeroes out the odometer?
[Optional] Plugin Code and/or Config
bg.BackgroundGeolocation.ready(bg.Config(
reset: true,
geolocation: bg.GeoConfig(
desiredAccuracy: bg.DesiredAccuracy.navigation,
distanceFilter: Platform.isIOS ? 100 : 50,
stopTimeout: 5,
geofenceModeHighAccuracy: true,
disableElasticity: false,
elasticityMultiplier: Platform.isIOS ? 1.5 : 1,
useSignificantChangesOnly: false,
disableLocationAuthorizationAlert: true,
locationAuthorizationRequest: 'Always',
showsBackgroundLocationIndicator: true,
filter: bg.LocationFilter(
odometerAccuracyThreshold: 100,
useKalman: false, // true breaks odometer
odometerUseKalmanFilter: true,
maxImpliedSpeed: 60.0,
),
),
activity: bg.ActivityConfig(
activityRecognitionInterval: 0,
stopOnStationary: false,
disableStopDetection: false,
triggerActivities: 'on_foot, walking, running, in_vehicle, on_bicycle',
),
http: bg.HttpConfig(
url: API_URL,
method: 'POST',
autoSync: true,
batchSync: true,
maxBatchSize: 1,
),
app: bg.AppConfig(
schedule: schedule,
stopOnTerminate: false,
startOnBoot: true,
enableHeadless: true,
heartbeatInterval: 300,
),
logger: bg.LoggerConfig(
debug: false,
logLevel: bg.LogLevel.error,
),
));[Optional] Relevant log output
bg.BackgroundGeolocation.ready(bg.Config(
reset: true,
geolocation: bg.GeoConfig(
desiredAccuracy: bg.DesiredAccuracy.navigation,
distanceFilter: Platform.isIOS ? 100 : 50,
stopTimeout: 5,
geofenceModeHighAccuracy: true,
disableElasticity: false,
elasticityMultiplier: Platform.isIOS ? 1.5 : 1,
useSignificantChangesOnly: false,
disableLocationAuthorizationAlert: true,
locationAuthorizationRequest: 'Always',
showsBackgroundLocationIndicator: true,
filter: bg.LocationFilter(
odometerAccuracyThreshold: 100,
useKalman: false, // true breaks odometer
odometerUseKalmanFilter: true,
maxImpliedSpeed: 60.0,
),
),
activity: bg.ActivityConfig(
activityRecognitionInterval: 0,
stopOnStationary: false,
disableStopDetection: false,
triggerActivities: 'on_foot, walking, running, in_vehicle, on_bicycle',
),
http: bg.HttpConfig(
url: API_URL,
method: 'POST',
autoSync: true,
batchSync: true,
maxBatchSize: 1,
),
app: bg.AppConfig(
schedule: schedule,
stopOnTerminate: false,
startOnBoot: true,
enableHeadless: true,
heartbeatInterval: 300,
),
logger: bg.LoggerConfig(
debug: false,
logLevel: bg.LogLevel.error,
),
));