function [ResultStruct] = GaitOutcomesTrunkAccFuncIH(inputData,FS,LegLength,WindowLen,ApplyRealignment,ApplyRemoveSteps) % DESCRIPTON: Trunk analysis of Iphone data without the need for step detection % CL Nov 2019 % Adapted LD feb 2021 (IH feb 2020) % koloms data of smartphone % 1st column is time data; % 2nd column is X, medio-lateral: + left, - right % 3rd column is Y, vertical: + downwards, - upwards % 4th column is Z, anterior- posterior : + forwards, - backwards %% Input Trunk accelerations during locomotion in VT, ML, AP direction % InputData: Acceleration signal with time and accelerations in VT,ML and % AP direction. % FS: sample frequency of the Accdata % LegLength: length of the leg of the participant in m; %% Output % ResultStruct: structure coninting all outcome measured calculated % Spectral parameters, spatiotemporal gait parameters, non-linear % parameters % fields and subfields: include the multiple measurements of a subject %% Literature % Richman & Moorman, 2000; [ sample entropy] % Bisi & Stagni Gait & Posture 2016, 47 (6) 37-42 % Kavagnah et al., Eur J Appl Physiol 2005 94: 468?475; Human Movement Science 24(2005) 574?587 [ synchrony] % Moe-Nilsen J Biomech 2004 37, 121-126 [ autorcorrelation step regularity and symmetry % Kobsar et al. Gait & Posture 2014 39, 553?557 [ synchrony ] % Rispen et al; Gait & Posture 2014, 40, 187 - 192 [realignment axes] % Zijlstra & HofGait & Posture 2003 18,2, 1-10 [spatiotemporal gait variables] % Lamoth et al, 2002 [index of harmonicity] % Costa et al. 2003 Physica A 330 (2003) 53–60 [ multiscale entropy] % Cignetti F, Decker LM, Stergiou N. Ann Biomed Eng. 2012 % May;40(5):1122-30. doi: 10.1007/s10439-011-0474-3. Epub 2011 Nov 25. [ % Wofl vs. Rosenstein Lyapunov] %% Settings Gr = 9.81; % Gravity acceleration, multiplication factor for accelerations StrideFreqEstimate = 1.00; % Used to set search for stride frequency from 0.5*StrideFreqEstimate until 2*StrideFreqEstimate StrideTimeRange = [0.2 4.0]; % Range to search for stride time (seconds) IgnoreMinMaxStrides = 0.10; % Number or percentage of highest&lowest values ignored for improved variability estimation N_Harm = 12; % Number of harmonics used for harmonic ratio, index of harmonicity and phase fluctuation LowFrequentPowerThresholds = ... [0.7 1.4]; % Threshold frequencies for estimation of low-frequent power percentages Lyap_m = 7; % Embedding dimension (used in Lyapunov estimations) Sen_m = 5; % Dimension, the length of the subseries to be matched (used in sample entropy estimation) Sen_r = 0.3; % Tolerance, the maximum distance between two samples to qualify as match, relative to std of DataIn (used in sample entropy estimation) NStartEnd = [100]; M = 5; % maximum template length ResultStruct = struct(); %% Filter and Realign Accdata % Apply Realignment & Filter data if ApplyRealignment % apply relignment as described in Rispens S, Pijnappels M, van Schooten K, Beek PJ, Daffertshofer A, van Die?n JH (2014). data = inputData; % ALREADY REORDERD: reorder data to 1 = V; 2= ML, 3 = AP% % Consistency of gait characteristics as determined from acceleration data collected at different trunk locations. Gait Posture 2014;40(1):187-92. [RealignedAcc, ~] = RealignSensorSignalHRAmp(data, FS); dataAcc = RealignedAcc; [B,A] = butter(2,20/(FS/2),'low'); dataAcc_filt = filtfilt(B,A,dataAcc); else % we asume that data for CONTROLS; reorder data to 1 = V; 2 = ML; 3 = AP %data = inputData(:,[3,2,1]); %[RealignedAcc, ~] = RealignSensorSignalHRAmp(data, FS); might not be necessary %dataAcc = RealignedAcc; data = inputData; dataAcc = inputData; [B,A] = butter(2,20/(FS/2),'low'); dataAcc_filt = filtfilt(B,A,inputData); end %% Step detection % Determines the number of steps in the signal so that the first 1 and last step in the signal can be removed if ApplyRemoveSteps % In order to run the step detection script we first need to run an autocorrelation function; [ResultStruct] = AutocorrStrides(dataAcc_filt,FS, StrideTimeRange,ResultStruct); % StrideTimeSamples is needed as an input for the stepcountFunc; StrideTimeSamples = ResultStruct.StrideTimeSamples; % Calculate the number of steps; [PksAndLocsCorrected] = StepcountFunc(data,StrideTimeSamples,FS); % This function selects steps based on negative and positive values. % However to determine the steps correctly we only need one of these; LocsStepsLD = PksAndLocsCorrected; %% Cut data & remove currents results % Remove 1 step in the beginning and end of data dataAccCut = dataAcc(LocsStepsLD(1):LocsStepsLD(end-1),:); dataAccCut_filt = dataAcc_filt(LocsStepsLD(1):LocsStepsLD(end-1),:); % Clear currently saved results from Autocorrelation Analysis clear ResultStruct; clear PksAndLocsCorrected; clear LocsSteps; % Change window length necessary if ApplyRemoveSteps? (16-2-2013 LD) WindowLen = 10*FS; else; dataAccCut = dataAcc; dataAccCut_filt = dataAcc_filt; end %% Calculate stride parameters ResultStruct = struct; % create empty struct % Run function AutoCorrStrides, Outcomeparameters: StrideRegularity AP/VT ,StrideTimeSamples,StrideTime [ResultStruct] = AutocorrStrides(dataAccCut_filt,FS, StrideTimeRange,ResultStruct); StrideTimeSamples = ResultStruct.StrideTimeSamples; % needed as input for other functions %% Calculate spatiotemporal stride parameters % Measures from height variation by double integration of VT accelerations and high-pass filtering [ResultStruct] = SpatioTemporalGaitParameters(dataAccCut_filt,StrideTimeSamples,ApplyRealignment,LegLength,FS,IgnoreMinMaxStrides,ResultStruct); %% Measures derived from spectral analysis AccVectorLen = sqrt(sum(dataAccCut_filt(:,1:3).^2,2)); % WindowLen -> 10*Fs OR on InputSignal [ResultStruct] = SpectralAnalysisGaitfunc(dataAccCut_filt,WindowLen,FS,N_Harm,LowFrequentPowerThresholds,AccVectorLen,ResultStruct); %% Calculation non-linear parameters; % cut into windows of size WindowLen N_Windows = floor(size(dataAccCut,1)/WindowLen); % Not sure if WindowLen should be different? N_SkipBegin = ceil((size(dataAccCut,1)-N_Windows*WindowLen)/2); LyapunovWolf = nan(N_Windows,3); SE= nan(N_Windows,3); for WinNr = 1:N_Windows; AccWin = dataAccCut(N_SkipBegin+(WinNr-1)*WindowLen+(1:WindowLen),:); for j=1:3 [LyapunovWolf(WinNr,j),~] = CalcMaxLyapWolfFixedEvolv(AccWin(:,j),FS,struct('m',Lyap_m)); [SE(WinNr,j)] = funcSampleEntropy(AccWin(:,j), Sen_m, Sen_r); % no correction for FS; SE does increase with higher FS but effect is considered negligible as range is small (98-104HZ). Might consider updating r to account for larger ranges. end end LyapunovWolf = nanmean(LyapunovWolf,1); SampleEntropy = nanmean(SE,1); ResultStruct.LyapunovWolf_V = LyapunovWolf(1); ResultStruct.LyapunovWolf_ML = LyapunovWolf(2); ResultStruct.LyapunovWolf_AP = LyapunovWolf(3); ResultStruct.SampleEntropy_V = SampleEntropy(1); ResultStruct.SampleEntropy_ML = SampleEntropy(2); ResultStruct.SampleEntropy_AP = SampleEntropy(3); %% Calculate RMS in each direction: added february 2021 by LD, CONSTRUCT: 'Pace' % Sekine, M., Tamura, T., Yoshida, M., Suda, Y., Kimura, Y., Miyoshi, H., ... & Fujimoto, T. (2013). A gait abnormality measure based on root mean square of trunk acceleration. Journal of neuroengineering and rehabilitation, 10(1), 1-7. Data_Centered = normalize(dataAcc_filt,'center','mean'); % The RMS coincides with the Sd since the Acc signals are transformed to give a mean equal to zero RMS = rms(Data_Centered); ResultStruct.RMS_V = RMS(1); ResultStruct.RMS_ML = RMS(2); ResultStruct.RMS_AP = RMS(3); end