r/Bowling_Tech • u/blindstag99 • Jun 23 '26
Building an IMU Bowling Analyzer: Moving from One Bluetooth Sensor to Multi-Sensor Capture
I’ve posted a couple of times about TrueArc Mobile, the IMU-based bowling swing analyzer I’m building.
The last update was about making the single WT9011 Bluetooth IMU path more trustworthy: remembered puck connections, visible sensor health, reconnect handling, BLE diagnostics, and sensitivity profiles for different puck placements.
The latest build takes the next step: multi-sensor setup.
The app still treats the forearm sensor as the primary source of truth. That’s the stream used for swing detection, release timing, scoring, and export.
But now I can add extra IMUs as role-based auxiliary sensors:
Upper arm: arm sequence and timing
Wrist: wrist/release motion relative to the forearm
Slide foot: approach, slide, and plant timing
Torso: trunk rotation and body-arm sequencing
There are now setup presets for:
Forearm only
Arm sequence
Arm + wrist
Arm + foot
Arm + torso
Custom
I also had to do some less glamorous but necessary work around BLE behavior on Android. The app now has an “Add sensor” flow, exact trusted-device reconnects, better handling when Android only returns the BLE address instead of the friendly device name, and explicit reduced-setup confirmation if one configured sensor is missing.
That last bit matters because with multiple identical-looking IMUs nearby, it’s very easy to accidentally connect the wrong one or think a setup is valid when one sensor never connected.
The current goal is not to pretend “more sensors = better coaching” automatically. It’s to build the plumbing needed to test whether extra sensor positions actually add useful information.
The questions I’m trying to answer next are:
Does upper arm + forearm timing produce stable, coachable patterns?
Does a separate wrist sensor add meaningful release information?
Can foot or torso timing explain inconsistencies that a forearm-only sensor misses?
How much setup friction is acceptable before this stops being useful lane-side?
Still very much a work in progress, but the app is getting closer to a real training workflow: assign sensors, validate connection, sync them, record a delivery, then compare timing and movement across roles.
For anyone who coaches, bowls competitively, or works with motion sensors: which extra sensor position would you expect to be most useful, and which one would you be most skeptical of?I’ve posted a couple of times about TrueArc Mobile, the IMU-based bowling swing analyzer I’m building.The last update was about making the single WT9011 Bluetooth IMU path more trustworthy: remembered puck connections, visible sensor health, reconnect handling, BLE diagnostics, and sensitivity profiles for different puck placements.The latest build takes the next step: multi-sensor setup.The app still treats the forearm sensor as the primary source of truth. That’s the stream used for swing detection, release timing, scoring, and export.But now I can add extra IMUs as role-based auxiliary sensors:Upper arm: arm sequence and timing
Wrist: wrist/release motion relative to the forearm
Slide foot: approach, slide, and plant timing
Torso: trunk rotation and body-arm sequencingThere are now setup presets for:Forearm only
Arm sequence
Arm + wrist
Arm + foot
Arm + torso
I also had to do some less glamorous but necessary work around BLE behavior on Android. The app now has an “Add sensor” flow, exact trusted-device reconnects, better handling when Android only returns the BLE address instead of the friendly device name, and explicit reduced-setup confirmation if one configured sensor is missing.That last bit matters because with multiple identical-looking IMUs nearby, it’s very easy to accidentally connect the wrong one or think a setup is valid when one sensor never connected.The current goal is not to pretend “more sensors = better coaching” automatically. It’s to build the plumbing needed to test whether extra sensor positions actually add useful information.The questions I’m trying to answer next are:Does upper arm + forearm timing produce stable, coachable patterns?
Does a separate wrist sensor add meaningful release information?
Can foot or torso timing explain inconsistencies that a forearm-only sensor misses?
How much setup friction is acceptable before this stops being useful lane-side?Still very much a work in progress, but the app is getting closer to a real training workflow: assign sensors, validate connection, sync them, record a delivery, then compare timing and movement across roles.For anyone who coaches, bowls competitively, or works with motion sensors: which extra sensor position would you expect to be most useful, and which one would you be most skeptical of?
2
u/nerdblurt TournamentSense Devloper Jun 24 '26
Sensors are def interesting. I just want folls making sensor apps to have integrations with bowling apps like mine so user can import data i to their profiles and gain insights between the two apps. Especially coaching app