6.2 Signals of the Muscles and Motions

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filt_angle = filt_angle(11:end);

filt_time_angle = time_angle_t(11:end);

%findpeaks

subplot(6,1,1)

[value, location] = findpeaks(value_force, "MinPeakProminence",50,...

"MinPeakHeight",340);

plot(time_force, value_force,'k-')

hold on

scatter(time_force(location), value, 'kx')

xlabel('Time t/s')

ylabel('Force F/N')

axis([0 10 250 500])

title('Findpeaks Force Data')

subplot(6,1,2)

[value, location] = findpeaks(value_angle_t, "MinPeakProminence", ...

100, "MinPeakHeight",150);

plot(time_angle_t, value_angle_t, 'k-')

hold on

scatter(time_angle_t(location), value, 'kx')

xlabel('Time t/s')

ylabel('Angle \alpha/deg')

axis([0 9 0 200])

title('Findpeaks Angle Data')

%Derivatives

subplot(6,1,3)

%calc first derivative

dydx = gradient(filt_angle) ./ gradient(filt_time_angle);

AA = find(dydx(1:end-1)>0 & dydx(2:end) < 0); %find maxima

AB = find(dydx(1:end-1) <0 & dydx(2:end) > 0); %find minima

plot(filt_time_angle, filt_angle,'k-')

hold on

%plot(filt_time_angle,dydx, 'k:')

scatter(filt_time_angle(AA), filt_angle(AA), 100, 'kx') %display ...

maxima

scatter(filt_time_angle(AB), filt_angle(AB), 100, 'kx') %display ...

minima

xlabel('Time t/s')

ylabel('Angle \alpha/deg')

axis([0 9 0 200])

title('First Derivative Zeros in Angle Data')