Ballistic pendulum 4Texas Instruments SensorTagRead the y-component of the accelerometer (Texas Instruments SensorTag like the CC2650 or the CC1350) put to the ballistic pendulum and determine the bullet speed and energy. Suspension length of the pendulum is determined by its period of oscillations.Ba4accYRawtcounttmaxaccYmaxminmMLspeedenergyposition_maxposition_minmin_positiont_firstdemi_Tstart_tto_measurestart_positiont_cutreimfftcount_measurefrequencyV2quotientoutpositionsumperiodquotient (1)count_cutcount_cutX100A1000
accYRaw
0.000598755
accY
start_position
position_max
position_min
accY
position_max
position_min
accY
to_measure
to_measure
accYRaw
L
count
max
min
m
M
L
0
tmax
count
speed
m
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min_position
1
max
min
m
M
frequency
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start_position
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demi_T
to_measure
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start_t
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start_t
t_cut
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im
count_cut
10
t_cut
to_measure
count_cutX10
t_cut
fft
2
quotient
1
period
count_measure
2
out
position
1
sum
count_measure
0.1
t
accY
speed
energy
V2
start_t
start_position
t_cut
to_measure
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out
quotient (1)
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accY
t_cut
to_measure