and working with the input and
output connectors on the ArduPilot.
This translates to ample opportunity
to slice a finger or two. Keep the
props off until the very end, and
don't forget to balance the props —
there are lots of examples on
YouTube if you're new at this.
Firmware setup of the ArduPilot
is a breeze, thanks to the menu-driven Mission Planner. Figure 12
shows the first step in the menu-driven setup, calibrating the R/C
unit mapping onto the ArduPilot.
I could have dropped into Arduino
source code and set these
parameters manually, but there
was no need. As you can see in
Figure 12, the next steps are listed
in order, starting with flight modes
and ending with the Planner. Setup
is painless and straightforward,
requiring all of five minutes to
Time to Get Physical
FIGURE 11. ArduPilot setup with external power
and USB connectivity to the Mission Planner software.
After setup and testing,
including checking and — if
necessary — correcting prop
rotation direction, it's time to drop
in a battery, boot the laptop, and
take it for a spin. Figure 13 shows
the quadcopter ready to go. Note
that there's no on-off switch on this
creature. Once you plug in the
battery, the ESCs issue various
beeps and buzzes, so you'd better
stand back. There is an arming
sequence which requires you to
hold the throttle stick in a certain
position for four seconds. A
constant red light signifies the
ArduPilot is armed and ready to go.
Figure 14 shows one of many
views available within the Mission
Planner. This view shows the
artificial horizon in the upper left,
geo-location on the right, and basic
sensor information from the
ArduPilot on the lower left. In this
example, ground speed is 0 (the quadcopter was on my
workbench), while altitude is shown as 2. 14 feet.
In addition to a realistic cockpit experience, you can
look at the raw sensor data in real time, as shown in
FIGURE 12. R/C
FIGURE 13. ArduPilot mounted within the quadcopter frame, ready to go.
Figure 15. In addition to instantaneous graphical displays
of roll, pitch, and yaw dials, you can see the plots of data
from the accelerometer and gyro over time.
I probably shouldn't reveal this, but at the time I
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