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Measured IMU position inside the iPhone 17

Tue, 27 Oct 2026 15:17:22 +0000

Hi all,

I wanted to know where exactly the accelerometer/gyroscope (IMU) sits inside my iPhone 17.

Apple does not publish this, and the estimates I found online turned out to be wrong. So I measured it with phyphox and a turntable. Sharing the method and result in case it is useful to others.

Device / software

iPhone 17 (iPhone18,3), iOS 26.6.1
phyphox 1.2.1, experiment "Acceleration with g" + "Gyroscope", 100 Hz, exported as .xlsx

Setup
The phone lies flat in a pocket made of pins on a wooden turntable, with its housing center about 120 mm from the axis and the long side tangential. Three runs were done in the same pocket:

display up (reference)
display down, flipped about the long (y) axis
display down, flipped about the short (x) axis

Each run: spin up by hand, then let it coast down.
(photo of the setup attached)

Method
Rigid-body model in the device frame (Apple/phyphox axes: x right, y up, z out of the display; phyphox accelerometer = specific force, i.e. +9.81 m/s² in z when lying display-up):

Code:
ax = wz^2 * lx + dwz/dt * ly + bx
ay = wz^2 * ly - dwz/dt * lx + by

(lx, ly) is the vector from the IMU to the rotation axis. bx and by absorb offset and tilt.

Linear least squares per run, using the same smoothing filter on data and regressors.
Time shift between gyro and accelerometer estimated by grid search: consistently +7 to +8 ms.
Confidence intervals from a moving-block bootstrap, because the residuals are autocorrelated.
The runs are combined via l_k = S_k*c - p, where p is the IMU position relative to the housing center, c the housing center -> axis vector, and S_k the flip of run k. Because the phone is flipped about both axes, p follows from the data without relying on the measured 120 mm or on the alignment angle.

Consistency check: the lever arm from the centripetal term (wz^2) and from the tangential term (dwz/dt) agree to about 1 mm in every run.

Result (origin = geometric center of the housing 149.6 x 71.5 mm, looking at the display, 95% CI):

x = -29.0 mm [-30.2, -27.9] (left half, about 7 mm from the left edge)
y = -0.1 mm [-1.4, +1.0] (practically at mid-height)
z: not observable with this method

(plot attached)

Caveats

Single device. I assumed about 1 mm repositioning tolerance in the pocket, and this dominates the CI. The pure statistical error is about 0.1 mm.
Sensor scale-factor errors are not included. A 1 % gyro scale error would shift the lever arm by about 2 %.
The data put the axis at about 116 mm from the housing center, not the 120 mm I measured with a ruler. Probably the turntable runs slightly eccentric. The result for p does not depend on this.
phyphox detail (from the iOS source): the accelerometer is raw CMAccelerometerData x (-9.81), the gyroscope is CMDeviceMotion.rotationRate (bias-corrected), not raw CMGyroData.

I'd be happy if someone could repeat this with another iPhone 17 or other models. I'll also share my Octave script and my measurement data.

Best regards,
Prototype

Code:
% Estimation of the IMU position (iPhone 17, phyphox) from several turntable runs
%
% Rigid-body model for a rotation about the device z-axis (phone frame, phyphox
% convention: specific force, +x right, +y up, +z out of the display). With
% l = (lx, ly) being the vector from the IMU to the rotation axis:
%   ax = wz²*lx + dwz/dt*ly + bx
%   ay = wz²*ly - dwz/dt*lx + by
% (bx, by: sensor offset + gravity leakage due to tilt)
%
% Combination of the runs: the phone sits in the same pocket in every run, only
% its orientation changes. With c = vector housing center -> rotation axis in the
% phone frame of the reference run (display up, see turntable.png) and p = IMU
% position relative to the housing center:
%   l_k = S_k*c - p
% S_k maps the reference placement into the phone frame of run k:
%   display up   (reference)            S = [ 1 0; 0  1]
%   display down, flipped about y-axis  S = [-1 0; 0  1]
%   display down, flipped about x-axis  S = [ 1 0; 0 -1]
%   display up,   rotated by 180°       S = [-1 0; 0 -1]
% Components of c that the runs cannot resolve are taken from the setup prior
% (R, phi). With the runs 'up' + 'down about y' this applies to the y-direction.

% clean up
clear all;
close all;
clc;

% settings
runs = struct( ...
  'file', {'Translation und Rotation 2026-09-29 16-10-10.xlsx', ...
           'Translation und Rotation 2026-10-26 15-35-40.xlsx', ...
           'Translation und Rotation 2026-10-27 13-36-20.xlsx'}, ...
  'S',    {[1 0; 0 1], [-1 0; 0 1], [1 0; 0 -1]}, ...
  'up',   {true, false, false});  % display up? (checked against az)
R      = 120;    % prior: distance housing center -> rotation axis (mm)
sigR   = 1;      % uncertainty of R (mm, 1 sigma)
phi    = 0;      % prior: angle of the rotation axis seen from the housing center (deg)
sigphi = 2;      % uncertainty of phi (deg, 1 sigma)
sigpos = 1;      % repositioning tolerance of the phone in the pocket (mm, 1 sigma)
Tsm    = 0.10;   % smoothing window (s)
taus   = -0.05 : 0.001 : 0.05;  % search grid for the gyro time shift (s)
Lblk   = 1.0;    % block length for the moving-block bootstrap (s)
B      = 2000;   % number of bootstrap samples
conf   = 0.95;   % confidence level
m2mm   = 1000;
rand('seed', 42);
randn('seed', 42);

% load a phyphox export (cached as .mat next to the .xlsx)
function [ACC, GYRO] = load_run(file)
  [~, name] = fileparts(file);
  cache = [name, '.mat'];
  if exist(cache, 'file')
    load(cache);
  else
    pkg load io;
    pkg load windows;
    ACC  = xlsread(file, 'Accelerometer');  % t (s), ax, ay, az (m/s²)
    GYRO = xlsread(file, 'Gyroscope');      % t (s), wx, wy, wz (rad/s)
    save('-v7', cache, 'ACC', 'GYRO');
  end
end

% build the (smoothed) linear model for a given gyro time shift tau
function [Y, X] = build_model(ta, ax, ay, tw, wz, tau, nsm, keep)
  w  = interp1(tw + tau, wz, ta, 'linear', 'extrap');
  dw = gradient(w, ta);
  % the same linear filter is applied to data and regressors -> model stays exact
  f  = @(v) movmean(v, nsm);
  W2 = f(w.^2)(keep);
  A  = f(dw)(keep);
  ax = f(ax)(keep);
  ay = f(ay)(keep);
  o  = ones(size(W2));
  z  = zeros(size(W2));
  Y  = [ax; ay];
  X  = [W2,  A, o, z;
        -A, W2, z, o];
end

% fit a single run: time shift, least squares, moving-block bootstrap
function r = fit_run(ACC, GYRO, Tsm, taus, Lblk, B)
  ta  = ACC(:, 1) - ACC(1, 1);
  tw  = GYRO(:, 1) - ACC(1, 1);
  dt  = median(diff(ta));
  nsm = max(1, round(Tsm/dt));
  % only use samples covered by the gyro, minus the filter edges
  keep = ta > tw(1) + max(abs(taus)) & ta < tw(end) - max(abs(taus));
  keep(1 : nsm) = false;
  keep(end - nsm + 1 : end) = false;
  n = sum(keep);

  ssr = zeros(size(taus));
  for k = 1 : numel(taus)
    [Y, X] = build_model(ta, ACC(:, 2), ACC(:, 3), tw, GYRO(:, 4), taus(k), nsm, keep);
    ssr(k) = sum((Y - X*(X\Y)).^2);
  end
  [~, kbest] = min(ssr);
  r.tau = taus(kbest);
  r.ssr = ssr;

  [Y, X] = build_model(ta, ACC(:, 2), ACC(:, 3), tw, GYRO(:, 4), r.tau, nsm, keep);
  th = X\Y;
  r.th  = th;
  r.rms = sqrt(mean((Y - X*th).^2));
  r.lx_rad = X(1:n, 1)\(Y(1:n) - th(3) - X(1:n, 2)*th(2));              % ax ~ wz²*lx
  r.lx_tan = X(n+1:end, 1)\(Y(n+1:end) - th(4) - X(n+1:end, 2)*th(2));  % ay ~ -dwz/dt*lx
  r.t = ta(keep);
  r.Y = Y;
  r.Ym = X*th;
  r.n = n;
  r.az = mean(ACC(:, 4));

  % residuals are strongly autocorrelated -> resample blocks
  L   = max(1, round(Lblk/dt));
  nb  = ceil(n/L);
  thb = zeros(B, numel(th));
  for b = 1 : B
    s   = randi(n - L + 1, nb, 1);
    idx = (s + (0 : L - 1))';
    idx = idx(1 : n)';
    thb(b, :) = ([X(idx, :); X(n + idx, :)]\[Y(idx); Y(n + idx)])';
  end
  r.thb = thb;
end

% combine runs: weighted least squares for u = [c; p] incl. setup prior on c
function u = combine(l, S, c0, Wc, sigpos)
  M = [];
  y = [];
  for k = 1 : numel(l)
    M = [M; [S{k}, -eye(2)]/sigpos];
    y = [y; l{k}/sigpos];
  end
  M = [M; [Wc, zeros(2)]];
  y = [y; Wc*c0];
  u = M\y;
end

% 1) fit every run
nr = numel(runs);
for k = 1 : nr
  [ACC, GYRO] = load_run(runs(k).file);
  res(k) = fit_run(ACC, GYRO, Tsm, taus, Lblk, B);
  if (res(k).az > 0) != runs(k).up
    warning('run %d: az = %.2f m/s² does not match up = %d', k, res(k).az, runs(k).up);
  end
end

% 2) combine the runs (nominal + Monte Carlo over bootstrap, prior and repositioning)
c0  = R*[cosd(phi); sind(phi)];
Ec  = [cosd(phi), -sind(phi); sind(phi), cosd(phi)];   % radial/tangential directions
Sc  = Ec*diag([sigR, R*sigphi*pi/180].^2)*Ec';          % prior covariance of c
Wc  = chol(inv(Sc));
S   = {runs.S};
l   = arrayfun(@(r) r.th(1:2)*m2mm, res, 'UniformOutput', false);
u   = combine(l, S, c0, Wc, sigpos);
ub  = zeros(B, 4);
for b = 1 : B
  lb = arrayfun(@(r) r.thb(b, 1:2)'*m2mm + sigpos*randn(2, 1), res, 'UniformOutput', false);
  ub(b, :) = combine(lb, S, c0 + chol(Sc)'*randn(2, 1), Wc, sigpos)';
end
c  = u(1:2);
p  = u(3:4);
pb = ub(:, 3:4);
% how much does each coordinate of p depend on the prior? (1 = only prior, 0 = only data)
J  = zeros(2);
for j = 1 : 2
  dc = zeros(2, 1);
  dc(j) = 1;
  du = combine(l, S, c0 + dc, Wc, sigpos) - u;
  J(:, j) = du(3:4);
end

% report
q  = [(1 - conf)/2, (1 + conf)/2];
ci = @(v) quantile(v, q);
printf('Single runs (vector IMU -> rotation axis in device coordinates, %2.0f%% CI, block bootstrap):\n', conf*100);
for k = 1 : nr
  r = res(k);
  printf('\n  Run %d: %s\n', k, runs(k).file);
  printf('    display %s (az = %+.2f m/s²), tau = %+.0f ms, RMS = %.3f m/s²\n', ...
         {'down', 'up  '}{runs(k).up + 1}, r.az, r.tau*1000, r.rms);
  printf('    lx = %8.2f mm  [%8.2f, %8.2f]   (radial %.2f / tangential %.2f)\n', ...
         r.th(1)*m2mm, ci(r.thb(:, 1)*m2mm), r.lx_rad*m2mm, r.lx_tan*m2mm);
  printf('    ly = %8.2f mm  [%8.2f, %8.2f]\n', r.th(2)*m2mm, ci(r.thb(:, 2)*m2mm));
  printf('    bx = %6.3f m/s², by = %6.3f m/s²\n', r.th(3), r.th(4));
end
printf('\nConsistency: residuals of the combined equations l_k = S_k*c - p (mm):\n');
for k = 1 : nr
  printf('  Run %d: [%+6.2f, %+6.2f]\n', k, S{k}*c - p - l{k});
end
printf('\nRotation axis seen from the housing center (reference placement): c = [%.2f, %.2f] mm\n', c);
printf('  => R = %.2f mm (prior %.1f +- %.1f), phi = %.2f deg (prior %.1f +- %.1f)\n', ...
       norm(c), R, sigR, atan2d(c(2), c(1)), phi, sigphi);
printf('\nIMU position relative to the housing center (x right, y up, looking at the display):\n');
printf('  x = %7.2f mm   [%7.2f, %7.2f]   share of prior R/phi: %3.0f %%\n', p(1), ci(pb(:, 1)), 100*norm(J(1, :)));
printf('  y = %7.2f mm   [%7.2f, %7.2f]   share of prior R/phi: %3.0f %%\n', p(2), ci(pb(:, 2)), 100*norm(J(2, :)));

% visualization
figure(1);
for k = 1 : nr
  r = res(k);
  subplot(nr, 2, 2*k - 1);
  plot(r.t, r.Y(1:r.n), '-', r.t, r.Ym(1:r.n), '--');
  grid on;
  ylabel(sprintf('run %d: a_x (m/s²)', k));
  subplot(nr, 2, 2*k);
  plot(r.t, r.Y(r.n+1:end), '-', r.t, r.Ym(r.n+1:end), '--');
  grid on;
  ylabel(sprintf('run %d: a_y (m/s²)', k));
end
xlabel('t (s)');
legend('measurement (smoothed)', 'model');

figure(2, 'position', [100 100 800 700]);
hold on;
rectangle('Position', [-71.5/2, -149.6/2, 71.5, 149.6], 'Curvature', 0.15);
plot(pb(:, 1), pb(:, 2), '.', 'Color', [0.7 0.7 0.9]);
plot(p(1), p(2), 'r+', 'MarkerSize', 14, 'LineWidth', 2);
plot(0, 0, 'k+');
axis equal;
axis([-60 60 -80 80]);
grid on;
xlabel('x (mm)');
ylabel('y (mm)');
title('iPhone 17: IMU position (looking at the display)');
legend('housing 71.5 x 149.6 mm', 'bootstrap / Monte Carlo', 'estimate', 'housing center', ...
       'location', 'eastoutside');
text(p(1) + 4, p(2) + 22, sprintf('x = %.1f mm [%.1f, %.1f]\ny = %.1f mm [%.1f, %.1f]\n(%2.0f%% CI)', ...
     p(1), ci(pb(:, 1)), p(2), ci(pb(:, 2)), conf*100));
print(2, 'imu_position_estimate.png', '-dpng', '-r120');

  turntable.png (Size: 441.58 KB / Downloads: 6)

  imu_position_estimate.png (Size: 28.67 KB / Downloads: 5)

  Translation und Rotation 2026-09-29 16-10-10.xlsx (Size: 237.56 KB / Downloads: 4)

  Translation und Rotation 2026-10-26 15-35-40.xlsx (Size: 143.61 KB / Downloads: 5)

  Translation und Rotation 2026-10-27 13-36-20.xlsx (Size: 141.27 KB / Downloads: 7)

Data transfer without WiFi

Fri, 25 Sep 2026 10:54:22 +0000

I wanted to measure the pressure in a closed metal lunch box, so WiFi did not work. I managed to create an experiment to generate a sine wave with a frequency corresponding to the air pressure, 1hPa=1Hz. With a second phone I was able do receive the sound and show the frequency=pressure over time. However, this is not very reliable, other sounds disturb the measurement. So I thought of using the vibration alarm as a signal source and a magnetometer as a receiver.
Does anyone know if the vibration generates (enough of) a magnetic field for this to work? And might there be a way to activate the vibration via phyphox?
Thanks a lot!

in version 1.2.1 Fadenpendel: inch instead of cm

Tue, 22 Sep 2026 23:00:38 +0000

More details on request.

Standort (GPS)

Fri, 18 Sep 2026 10:01:55 +0000

Ich war heute am geodätischen Referenzpunkt und habe den Referenzwert mit dem Wert in der App verglichen.
In der App wird unter Standort(GPS) -> Einfach die "Genauigkeit" angezeigt. Der hier angezeigte Wert ist vermutlich die Streuung der Messwerte aber nicht die Genauigkeit der Position. Das sollte dann aber auch in der App so bezeichnet werden.
Weiterhin wird eine zurückgelegte Entfernung von 10 m angezeigt, obwohl das Smartphone nicht bewegt wurde. Diesen Fehler könnte man verringern, wenn zwischen dem Start des Experimentes und der Auswertung / Anzeige eine Verweilzeit von ca. 20 sec. programmiert würde. (Unter dem Menü Bewegung oder Position kann man erkennen, das die App eine gewisse Zeit braucht, bis die Werte nicht mehr so stark hin- und herspringen)

question about the tone generator

Thu, 17 Sep 2026 08:46:33 +0000

Hello,

I am playing with the tone generator, new version, using the advanced setting option. I am wondering what the parameter "pan left/right" is controlling? I assumed it would add a phase in the channel output (something like pan=1 is +PI, pan=-1 is -PI), but I see no difference in the signal when I vary this parameter.

Any help is appreciated,

Cheers,

Fred

help with rangefilter

Mon, 31 Aug 2026 10:02:28 +0000

hello,

for a natural swimming pool with 2 pools I build the following:
2 Sender where each read 2 sensor and deliver the current values it via lora
1 receiver, which can ask for history data via phyphox.
I wish to create a rangefilte that filter incorrect data (e.g. -127 °C)
If i build the phybox file without rangefilter, the app displays the correct raw data.
with rangefilter it displays only the batteryvoltage, which is not filterd

so any idea, whats the problem?

Kiwibad.phyphox (Size: 7.21 KB / Downloads: 79)

Zwei Container zeitlich synchronisieren

Tue, 25 Aug 2026 10:48:02 +0000

Hallo liebe Phyphox Anwender,

ich habe ein Problem beim Zusammenführen von zwei Messgeräten.
Der Laborino (BLE) soll die magnetische Flussdichte in der Nähe eines geraden stromdurchflossenen Leiters messen, während man am Netzgerät die Stromstärke erhöht welche vom OWON-Mutimeter (BLE) gememessen wird und ebenfalls an phyphox die Daten sendet.

Die beiden Größen welche ich in einem Diagramm gegenüberstellen will, kommen demnach von zwei verschiedenen BLE Geräten (Laborino und OWON-Multimeter). So wie ich das verstehe ist mein Problem, dass der zeitliche Zusammenhang der Größen nicht da ist und somit kein sinnvolles Diagramm entstehen kann (z.B in einem Container sind 100 Werte während im anderen bereits 1000 sind) Um das zu lösen habe ich bereits mit dedizierten Containern nur für die Diagrammerstellung herumgespielt. z.B um immer dann den letzten Magnetfeldwert zu lesen, wenn ein neuer Strom- bzw Zeitmessung vom OWON hereinkommt (d/dt größer null). Diese Werte (Container Größe 1) werden in einen Container (Größe 0) angehangen. Und auch der aktuelle Magnetfeldwert soll dann in einen eigenen Container ((MAG_sing) für Single) gespeichert werden. Dieser wird dann an den eigenen Container Größe 0 angehangen.

Da es ein eigenes Laborion Experiment ist, wird es nicht bei euch wahrscheinlich nicht Laufen, aber vielleicht hilft der Code schon weiter.

Es müsste sich mit dem OWON Multimeter und dem Smarphone Magnetometer nachstellen lassen.

Code:



    OerstedTeil2
    Laborino2-Experimente
    Messung mag. Flussdichte und Strom

    
        
        BT_INC
        BT_OUTC

        
        TIME
        RAD
        MAG
        MAG_sing
        dt
        t
        I
		I_sync
		MAG_sync

        
        tin
        Iin
        18value
        18-value
        18signedvalue
        18bitmask
        18decfac
        18prefac



    

    
        
            BT_INC

            TIME

            RAD

            MAG
        

        
            18value

            18bitmask

            tin
        
    

    
        
            426

            BT_OUTC
        
    

    
        
        
            BT_INC
            0
            
            TIME
        

        
            BT_INC
            0
            
            RAD
        

        
            BT_INC
            0
            
            MAG
        


        
        
            32768
            18value
            18-value
        

        
            18value
            32767
            18-value
            18value
            18signedvalue
        

        
            18bitmask
            18decfac
        

        
            18bitmask
            18prefac
        

        
            18signedvalue
            18decfac
            18prefac
            Iin
        

        
            Iin
            I
        

        
            tin
            t
        
		
		
		
		

		
			t
			dt
		

		
			dt
			0

			
			Iin
			I_sync
		
		
			dt
			0

			
			MAG
			MAG_sing
		
        
            MAG_sing
            MAG_sync
        

    

    

    
        

        

            TIME
            MAG
        

        

        

			   
            t
            I
        


    
        
            I_sync
            MAG_sync
        

    MAG_sync


    I_sync

Vibration Brücke

Tue, 21 Jul 2026 08:48:50 +0000

Hallo,

Kann man die Schwingungen einer Fußgängerbrücke mit Phyphox messen und analysieren? Ich frage mich ob das möglich ist indem man auf die Brücke springt und die Schwingungen so aufzeichnet. Beeinflusst die Bewegung des Telefons in der Hand möglicherweise die Messung?

Wenn es geht, wie findet man die Resonanz/ Grund frequenzen. Benötige ich dafür beispielsweise Python, oder ist die Analyse direkt in der App möglich? Danke für ihre Antwort!

phyphox - roller coaster mode - accelaration z direction

Sat, 04 Jul 2026 20:59:00 +0000

This week I enjoyed a supervised flight in a glider (small plane without engine). The flight starts with the plane being pulled by a cable on a winch to approx. 500 m height under an angle of some 40°.
I used phyphox in "roller coaster" mode, i.e. measuring a in x (along short sides of phone), y (along long side of phone) and z (perpendicular to phone) directions.

I was wondering whether the tilt of the phone influences the measurements in the z direction. In other words, should I correct the values by the cos of the tilt angle?

Thank you.

P.S. Sorry if this question has come up before. I could not find it in the forums.

About fluctuating sampling rate

Wed, 10 Jun 2026 07:24:48 +0000

Hi, thank you for making a great app!
I am doing the Acceleration Spectrum experiment with an iPhone 12 Pro Max (whose accelermoter's sampling rate is at 100Hz).
Since I want to limit the sampling rate to another number, I changed a bit in the code.
-
# I changed to 50 and 80

I succeeded in loading the experiment to my phone already.
However, there were some strange things:
- For the 50Hz case: Sometimes the sampling rate starts at 33Hz and then slowly reaching 45 Hz and fluctuates; sometimes it starts perfectly at 50Hz and does not change at all
- For the 80Hz case: The sampling rate is always at 50Hz

I would really appreciate it if you could let me know what the reasons might be.
And maybe a way to fix?

Thank you for your time!

About loading a .phyphox file into the app + Missing part

Mon, 08 Jun 2026 04:29:39 +0000

Hello, I hope you guys are all doing well.

I am having a problem in terms of loading a .phyphox file into the app.
My purpose for doing this is to limit the accelerometer's sampling rate to 50Hz.

1) I originally took the code from https://github.com/phyphox/phyphox-exper...um.phyphox
Then I changed to so as to match the current version of Phyphox on my phone; and to

When I loaded this experiment onto Google Drive and logged in phyphox://[URL], the error shows as
''exp_error
Could not load experiment: Invalid experiment file. Unkown file format.''
I would really appreciate if you guys could show me where I could have gone wrong in my practice.

2) I managed to add the experiment to Phyphox by sending through email and opening directly with Phyphox.
However, there is a function missing in Github version compared to the version from AppStore,
which is the Peak Frequency (Hz) - Time graph in the History section (you can see in my attachment below.
Where should I find the code for the missing part?

Thank you so much for your time!

スクリーンショット 2026-06-08 132628.png (Size: 60 KB / Downloads: 205)

Uploading data

Wed, 27 May 2026 14:32:09 +0000

Hello,
I had a question regarding whether there is any way to upload externally collected sensor/data files into the app for analysis or visualization.
More specifically, I was curious if it would be possible to use uploaded data to analyze things such as barometric pressure changes from an event like a gunshot or other impulse-type event, rather than only using live sensor data collected directly from the phone.
I know Phyphox can record pressure sensor data live from supported devices, but I was wondering if there is any capability for importing datasets afterward for review, graphing, or comparison.
Any insight would be appreciated. Thanks!

Slider lazy/notinit value big issue

Tue, 12 May 2026 09:34:14 +0000

Hi,
I have big issue with slider component (other have the same issue) with ESP32 library.
PhyphoxBLE::read(...)
return always 0 (lazy not init value) until I do some change on Slider.
Slider example:

I can workaround it by

Code:
if(readValue) {
   destvalue = readValue;
}

but only for cases where slider doesn't have 0, like <1,5>, but for range <-5,5> i have 0 and it cause another issue.

Question is: how to change not init/lazy value by NaN vale or MAX_VALUE to prevent "Null" as 0.

Or how to force phyphox to init component (e.g. Slider) to start sending real values, even it is not touched?

This issue blow my application which I'm working on since 2 weeks.

I tried to change code of libraries to return not init values as NaN, but I failed. Is it possible to do on ESP32 code, or do we need to change code of phyphox?

"Add Experiment for Bluetooth Device" reporting when Bluetooth disabled.

Sun, 26 Apr 2026 09:04:13 +0000

Hiio!

Amazing toolbox! Thankyou for making it available for everyone! ☺️

Attempting to use the
"Add Experiment for Bluetooth Device"
when Bluetooth is disabled gives
"Bluetooth scan error. Bluetooth Low Energy is not supported on Android Versions lower than 4.3"
Tried re-running with Bluetooth enabled, and it proceeds just fine.

Thought the error-message could be improved to suggest enabling Bluetooth.

Thanks

T

Hilfe: Web-Dashboard für ferngesteuertes Auto

Wed, 22 Apr 2026 19:27:51 +0000

Hallo :-)

Ich arbeite grade an meinem Bachelorprojekt und bräuchte euren Rat. Ich möchte ein Smartphone auf ein ferngesteuertes Auto befesteigen um die Fahrdynamik zu tracken und die Live-Daten in ein Web Dashboard zu übertragen.

Mein Ziel ist es, die JSON Daten aus dem Experiment "Beschleunigung ohne g" per Fernzugriff auf mein Tablet zu senden und Geschwindigkeit, Brems und Kurvenverhalten in einem selbstgebauten Dashboard mit Balken anzuzeigen. Das HTML Gerüst ist fertig und ich hab es mit der Java Script "fetch" Funktion probiert, aber es funktioniert noch nicht. Könnt ihr mir da eventuell weiterhelfen? Oder wisst ihr zufällig, ob es für so ein Web-Dashboard schon fertige Code Beispiele gibt oder ob jemand aus der Community schon mal etwas Ähnliches umgesetzt hat?

Ich wäre über jeden Tipp super dankbar!