More refined session state (#33)

* A more refined rowing session state (PM5)

Introduces a more refined session state needed for the PM5 rower session simulation, as well as a cleaner setup for the metrics to stop when the rower is stopped.

* Added the WorkoutState and rowingState

Added the WorkoutState and rowingState to the PM5 interface, to prevent EXR to start too early.

* Added a link to the brilliant work of Nomath

Added a link to Nomath's work, as it is a brilliant piece of work that independently verifies our calculations and provides a basis for support of the Concept2 rower.

* Bugfix in Instantanous Torque calculation

The Instantanous Torque calculation wasn't cleaned up sufficiently, causing issues in the powercurve.

* unifies reset of heartrate value at different places

* unifies naming with other variables status -> state

* just some minor link adjustments in documentation

Co-authored-by: Lars Berning <151194+laberning@users.noreply.github.com>

app/ble/pm5/characteristic/GeneralStatus.js

@@ -46,9 +46,9 @@ export default class GeneralStatus extends bleno.Characteristic {
       // intervalType: UInt8 will always use 255 (NONE)
       bufferBuilder.writeUInt8(255)
       // workoutState: UInt8 0 WAITTOBEGIN, 1 WORKOUTROW, 10 WORKOUTEND
-      bufferBuilder.writeUInt8(1)
+      bufferBuilder.writeUInt8(data.sessionState === 'rowing' ? 1 : (data.sessionState === 'waitingForStart' ? 0 : 10))
       // rowingState: UInt8 0 INACTIVE, 1 ACTIVE
-      bufferBuilder.writeUInt8(1)
+      bufferBuilder.writeUInt8(data.sessionState === 'rowing' ? 1 : 0)
       // strokeState: UInt8 2 DRIVING, 4 RECOVERY
       bufferBuilder.writeUInt8(data.strokeState === 'DRIVING' ? 2 : 4)
       // totalWorkDistance: UInt24LE in 1 m

app/engine/RowingEngine.js

@@ -149,11 +149,7 @@ function createRowingEngine (rowerSettings) {
     // Calculate the key metrics
     recoveryLinearDistance = Math.pow((dragFactor / rowerSettings.magicConstant), 1.0 / 3.0) * recoveryPhaseAngularDisplacement
     totalLinearDistance += recoveryLinearDistance
-    if (currentDt > 0) {
+    currentTorque = calculateTorque(currentDt)
-      previousAngularVelocity = currentAngularVelocity
-      currentAngularVelocity = angularDisplacementPerImpulse / currentDt
-      currentTorque = rowerSettings.flywheelInertia * ((currentAngularVelocity - previousAngularVelocity) / currentDt) + dragFactor * Math.pow(currentAngularVelocity, 2)
-    }
     linearCycleVelocity = calculateLinearVelocity()
     averagedCyclePower = calculateCyclePower()
 
@@ -186,11 +182,7 @@ function createRowingEngine (rowerSettings) {
     // Update the key metrics on each impulse
     drivePhaseAngularDisplacement = ((totalNumberOfImpulses - flankDetector.noImpulsesToBeginFlank()) - drivePhaseStartAngularDisplacement) * angularDisplacementPerImpulse
     driveLinearDistance = Math.pow((dragFactor / rowerSettings.magicConstant), 1.0 / 3.0) * drivePhaseAngularDisplacement
-    if (currentDt > 0) {
+    currentTorque = calculateTorque(currentDt)
-      previousAngularVelocity = currentAngularVelocity
-      currentAngularVelocity = angularDisplacementPerImpulse / currentDt
-      currentTorque = calculateTorque(currentDt)
-    }
     if (workoutHandler) {
       workoutHandler.updateKeyMetrics({
         timeSinceStart: totalTime,
@@ -213,11 +205,7 @@ function createRowingEngine (rowerSettings) {
     // driveEndAngularVelocity = angularDisplacementPerImpulse / flankDetector.impulseLengthAtBeginFlank()
     driveLinearDistance = Math.pow((dragFactor / rowerSettings.magicConstant), 1.0 / 3.0) * drivePhaseAngularDisplacement
     totalLinearDistance += driveLinearDistance
-    if (currentDt > 0) {
+    currentTorque = calculateTorque(currentDt)
-      previousAngularVelocity = currentAngularVelocity
-      currentAngularVelocity = angularDisplacementPerImpulse / currentDt
-      currentTorque = calculateTorque(currentDt)
-    }
     // We display the AVERAGE speed in the display, NOT the top speed of the stroke
     linearCycleVelocity = calculateLinearVelocity()
     averagedCyclePower = calculateCyclePower()
@@ -252,11 +240,7 @@ function createRowingEngine (rowerSettings) {
     // Update the key metrics on each impulse
     recoveryPhaseAngularDisplacement = ((totalNumberOfImpulses - flankDetector.noImpulsesToBeginFlank()) - recoveryPhaseStartAngularDisplacement) * angularDisplacementPerImpulse
     recoveryLinearDistance = Math.pow((dragFactor / rowerSettings.magicConstant), 1.0 / 3.0) * recoveryPhaseAngularDisplacement
-    if (currentDt > 0) {
+    currentTorque = calculateTorque(currentDt)
-      previousAngularVelocity = currentAngularVelocity
-      currentAngularVelocity = angularDisplacementPerImpulse / currentDt
-      currentTorque = calculateTorque(currentDt)
-    }
     if (workoutHandler) {
       workoutHandler.updateKeyMetrics({
         timeSinceStart: totalTime,

app/engine/RowingStatistics.js

@@ -24,14 +24,14 @@ function createRowingStatistics (config) {
   const powerRatioAverager = createWeightedAverager(numOfDataPointsForAveraging)
   const caloriesAveragerMinute = createMovingIntervalAverager(60)
   const caloriesAveragerHour = createMovingIntervalAverager(60 * 60)
-  let trainingRunning = false
+  let sessionState = 'waitingForStart'
   let rowingPausedTimer
   let heartrateResetTimer
   let distanceTotal = 0.0
   let durationTotal = 0
   let strokesTotal = 0
   let caloriesTotal = 0.0
-  let heartrate
+  let heartrate = 0
   let heartrateBatteryLevel = 0
   let lastStrokeDuration = 0.0
   let instantaneousTorque = 0.0
@@ -51,8 +51,6 @@ function createRowingStatistics (config) {
   }
 
   function handleStrokeEnd (stroke) {
-    if (!trainingRunning) startTraining()
-
     // if we do not get a stroke for timeBetweenStrokesBeforePause milliseconds we treat this as a rowing pause
     if (rowingPausedTimer)clearInterval(rowingPausedTimer)
     rowingPausedTimer = setTimeout(() => pauseRowing(), timeBetweenStrokesBeforePause)
@@ -85,6 +83,7 @@ function createRowingStatistics (config) {
   // initiated by the rowing engine in case an impulse was not considered
   // because it was too large
   function handlePause (duration) {
+    sessionState = 'paused'
     caloriesAveragerMinute.pushValue(0, duration)
     caloriesAveragerHour.pushValue(0, duration)
     emitter.emit('rowingPaused')
@@ -94,6 +93,7 @@ function createRowingStatistics (config) {
   function handleRecoveryEnd (stroke) {
     // todo: we need a better mechanism to communicate strokeState updates
     // this is an initial hacky attempt to see if we can use it for the C2-pm5 protocol
+    if (sessionState !== 'rowing') startTraining()
     durationTotal = stroke.timeSinceStart
     powerAverager.pushValue(stroke.power)
     speedAverager.pushValue(stroke.speed)
@@ -137,8 +137,9 @@ function createRowingStatistics (config) {
     // todo: due to sanitization we currently do not use a consistent time throughout the engine
     // We will rework this section to use both absolute and sanitized time in the appropriate places.
     // We will also polish up the events for the recovery and drive phase, so we get clean complete strokes from the first stroke onwards.
-    const averagedStrokeTime = strokeAverager.getAverage() > minimumStrokeTime && strokeAverager.getAverage() < maximumStrokeTime && lastStrokeSpeed > 0 ? strokeAverager.getAverage() : 0 // seconds
+    const averagedStrokeTime = strokeAverager.getAverage() > minimumStrokeTime && strokeAverager.getAverage() < maximumStrokeTime && lastStrokeSpeed > 0 && sessionState === 'rowing' ? strokeAverager.getAverage() : 0 // seconds
     return {
+      sessionState,
       durationTotal,
       durationTotalFormatted: secondsToTimeString(durationTotal),
       strokesTotal,
@@ -147,14 +148,14 @@ function createRowingStatistics (config) {
       caloriesPerMinute: caloriesAveragerMinute.getAverage() > 0 ? caloriesAveragerMinute.getAverage() : 0,
       caloriesPerHour: caloriesAveragerHour.getAverage() > 0 ? caloriesAveragerHour.getAverage() : 0,
       strokeTime: lastStrokeDuration, // seconds
-      distance: lastStrokeDistance > 0 && lastStrokeSpeed > 0 ? lastStrokeDistance : 0, // meters
+      distance: lastStrokeDistance > 0 && lastStrokeSpeed > 0 && sessionState === 'rowing' ? lastStrokeDistance : 0, // meters
-      power: powerAverager.getAverage() > 0 && lastStrokeSpeed > 0 ? powerAverager.getAverage() : 0, // watts
+      power: powerAverager.getAverage() > 0 && lastStrokeSpeed > 0 && sessionState === 'rowing' ? powerAverager.getAverage() : 0, // watts
       split: splitTime, // seconds/500m
       splitFormatted: secondsToTimeString(splitTime),
-      powerRatio: powerRatioAverager.getAverage() > 0 && lastStrokeSpeed > 0 ? powerRatioAverager.getAverage() : 0,
+      powerRatio: powerRatioAverager.getAverage() > 0 && lastStrokeSpeed > 0 && sessionState === 'rowing' ? powerRatioAverager.getAverage() : 0,
       instantaneousTorque: instantaneousTorque,
-      strokesPerMinute: averagedStrokeTime !== 0 ? (60.0 / averagedStrokeTime) : 0,
+      strokesPerMinute: averagedStrokeTime !== 0 && sessionState === 'rowing' ? (60.0 / averagedStrokeTime) : 0,
-      speed: speedAverager.getAverage() > 0 && lastStrokeSpeed > 0 ? (speedAverager.getAverage() * 3.6) : 0, // km/h
+      speed: speedAverager.getAverage() > 0 && lastStrokeSpeed > 0 && sessionState === 'rowing' ? (speedAverager.getAverage() * 3.6) : 0, // km/h
       strokeState: lastStrokeState,
       heartrate,
       heartrateBatteryLevel
@@ -162,11 +163,11 @@ function createRowingStatistics (config) {
   }
 
   function startTraining () {
-    trainingRunning = true
+    sessionState = 'rowing'
   }
 
   function stopTraining () {
-    trainingRunning = false
+    sessionState = 'stopped'
     if (rowingPausedTimer)clearInterval(rowingPausedTimer)
   }
 
@@ -182,6 +183,7 @@ function createRowingStatistics (config) {
     powerAverager.reset()
     speedAverager.reset()
     powerRatioAverager.reset()
+    sessionState = 'waitingForStart'
   }
 
   // clear the metrics in case the user pauses rowing
@@ -191,6 +193,7 @@ function createRowingStatistics (config) {
     speedAverager.reset()
     powerRatioAverager.reset()
     lastStrokeState = 'RECOVERY'
+    sessionState = 'paused'
     emitter.emit('rowingPaused')
   }
 

docs/attribution.md

@@ -6,9 +6,11 @@ Open Rowing Monitor uses some great work by others. Thank you for all the great
 
 * Dave Vernooy's project description on [ErgWare](https://dvernooy.github.io/projects/ergware) has some good information on the maths involved in a rowing ergometer.
 
-* Bluetooth is quite a complex beast, luckily the Bluetooth SIG releases all the [specifications here](https://www.bluetooth.com/specifications/specs).
+* Nomath has done a very impressive [Reverse engineering of the actual workings of the Concept 2 PM5](https://www.c2forum.com/viewtopic.php?f=7&t=194719), including experimentally checking drag calculations.
 
-* The app icon is based on this [image of a rowing machine](https://thenounproject.com/term/rowing-machine/659265) by [Gan Khoon Lay](https://thenounproject.com/leremy/) licensed under [CC BY 2.0](https://creativecommons.org/licenses/by/2.0/).
+* Bluetooth is quite a complex beast, luckily the Bluetooth SIG releases all the [Bluetooth Specifications](https://www.bluetooth.com/specifications/specs).
+
+* The app icon is based on this [Image of a rowing machine](https://thenounproject.com/term/rowing-machine/659265) by [Gan Khoon Lay](https://thenounproject.com/leremy/) licensed under [CC BY 2.0](https://creativecommons.org/licenses/by/2.0/).
 
 * The frontend uses some icons from [Font Awesome](https://fontawesome.com/), licensed under [CC BY 4.0](https://creativecommons.org/licenses/by/4.0/).
 

docs/physics_openrowingmonitor.md

@@ -97,11 +97,11 @@ There are several key metrics that underpin the performance measurement of a row
 
 * The **Angular Velocity** of the flywheel in Radians/second: in essence the number of (partial) rotations of the flywheel per second. As the *Angular Displacement* is fixed for a specific rowing machine, the *Angular Velocity* is (*angular displacement between impulses*) / (time between impulses);
 
-* The **Angular Acceleration** of the flywheel in Radians/second^2^: the acceleration/deceleration of the flywheel;
+* The **Angular Acceleration** of the flywheel (in Radians/second^2): the acceleration/deceleration of the flywheel;
 
-* The *estimated* **Linear Distance** of the boat in Meters: the distance the boat is expected to travel;
+* The *estimated* **Linear Distance** of the boat (in Meters): the distance the boat is expected to travel;
 
-* _estimated_ **Linear Velocity** of the boat in Meters/Second: the speed at which the boat is expected to travel.
+* _estimated_ **Linear Velocity** of the boat (in Meters/Second): the speed at which the boat is expected to travel.
 
 ## Measurements during the recovery phase
 
@@ -116,7 +116,7 @@ Although not the first phase in a cycle, it is an important phase as it deducts
 
 In the recovery phase, the only force exerted on the flywheel is the (air/water/magnetic)resistance. Thus we can calculate the Drag factor of the Flywheel based on the entire phase.
 
-As [[1]](#1) describes in formula 7.2:
+As [[1]](#1) describes in formula 7.2, which is also experimentally verified by Nomath on a Concept 2 [[5]](#5):
 
 > <img src="https://render.githubusercontent.com/render/math?math=k=Id(1/\omega)/dt">
 
@@ -280,3 +280,5 @@ Again, this is a systematic (overestimation) of the power, which will be systema
 <a id="3">[3]</a> Dave Vernooy, "Open Source Ergometer ErgWare" <https://dvernooy.github.io/projects/ergware/>
 
 <a id="4">[4]</a> <https://github.com/dvernooy/ErgWare/blob/master/v0.5/main/main.ino>
+
+<a id="5">[5]</a> Fan blade Physics and a Peek inside C2's Black Box, Nomath <https://www.c2forum.com/viewtopic.php?f=7&t=194719>