The experiment generating the data for Problem 1 was re-done using an improved a

Question

The experiment generating the data for Problem 1 was re-done using an improved accelerometer obtaining more accurate acceleration data at a higher frequency (every 0.1 ms). The measured data is provided on Blackboard as a file a.mat containing the acceleration data in multiples of g and a file t.mat containing the time of measurements in ms. Calculate the SI index and determine if the football helmet is safe to use. Problem 6 required submission: Hardcopy printout of well commented script you coded to solve this problem; State which method you have chosen; Hardcopy printout, of the calculated SI; Statement if the football helmet is safe to use according to the SI index. The Gadd Severity Index SI is used to certify football helmets, it is calculated from the acceleration history a(t) during impact using the following integral, SI = integral_0^5_1 a(t)^2.5 dt. The acceleration is given in multiples of g (gravitational acceleration) and t_1 is the duration of the impact event in ms. SI values above 1200 indicate an unsafe football helmet, resulting in severe head injury. Acceleration data was measured for a helmet and is given in the following table

Explanation / Answer

times = 0:5:60; %creating a times array
accelerations = [0, 4, 10, 15, 25, 20, 34, 42, 47, 20, 13, 8, 3]; %accelerations provided

fun = []; %function values for each time
ts = []; %time in seconds
for t = times
    fun(end+1) = (accelerations(t/5+1)*9.81)^2.5;
    ts(end+1) = t*10^-3;
end

SI = trapz(ts, fun); %integration from discrete points
disp(SI);
if SI>1200
    disp('Unsafe')
end

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