Since it took over an hour to recover the rocket the system sat in flight mode (i.e., on) until the BQ3060 killed the power to preserve the pack. We had the rocket net hub set up to send health messages including battery conditions to the flight comptuer which was logging.
Here we see the battery pack (4s;1p) voltage over it's entire discharge life:
%matplotlib inline
import numpy
import utils
from matplotlib import rcParams
rcParams.update({'font.size': 12})
t_0 = 202945201730391 # Liftoff, see: first-look.ipynb
columns = numpy.loadtxt("../raw/fcf_full_log_RNHH.csv", delimiter=',', unpack=True)
time = columns[1]
temp = columns[2]
v_bus = columns[6]
I_bus = columns[7]
v_1 = columns[9]
v_2 = columns[10]
v_3 = columns[11]
v_4 = columns[12]
v_pack = columns[13]
time = numpy.subtract(time, t_0)
time = numpy.divide(time, 1e9)
fig = utils.Plot("Launch 11 Battery Pack Life", "Time [min:sec]", "Pack Voltage [V]")
fig.plot(time, v_pack, lw=1.4)
fig.xlim([-1200, 4800])
fig.timex(sep=600)
fig.note('Shore Power Off', (-520, 16.45), (60, -15))
fig.note('Launch!', (0, 15.65), (60, 15))
fig.note('End of WiFi telemetry', (412.6, 15.4), (60, 15))
fig.show()
That's for the whole pack, what about the individual cells?
fig = utils.Plot("Launch 11 Battery Cell Life", "Time [min:sec]", "Cell Voltage [V]")
fig.plot(time, v_1, color=utils.red, lw=1.4, label="Cell 1")
fig.plot(time, v_2, color=utils.green, lw=1.4, label="Cell 2")
fig.plot(time, v_3, color=utils.blue, lw=1.4, label="Cell 3")
fig.plot(time, v_4, color='#ff22cc', lw=1.4, label="Cell 4")
fig.xlim([-600, 4500])
fig.timex(sep=600)
fig.legend()
fig.show()
Cell's 2 and 3 stayed consistantly higher than the other two, and in fact never got below 3.6 Volts.
How about power output? First current (negative because we are draining the battery):
fig = utils.Plot("Launch 11 Bus Current", "Time [min:sec]", "Current [Amp]")
fig.plot(time, I_bus, lw=1.4)
fig.xlim([-1200, 4800])
fig.timex(sep=600)
fig.show()
And power usage, since we also know the system voltage:
power = numpy.multiply(I_bus, v_bus)
power = numpy.abs(power)
fig = utils.Plot("Launch 11 System Power", "Time [min:sec]", "Power [W]")
fig.plot(time, power, lw=1.4)
fig.xlim([-1200, 4800])
fig.ylim([15, 50])
fig.timex(sep=600)
fig.show()