SPORT ROCKETRY MAY/JUNE 2017 23
Figure 5. The completed
ANDRover.
The stack was held together with two 3/8"
threaded steel rods. Each assembly was
held in place with nylon bolts. The lander
was designed to be fully autonomous and
featured redundant power and dual Feath-
erweight Raven 3 flight systems for logic.
Dual custom onboard 1080p DVRs were
incorporated to capture both the landing
and rover deployment events; one lens
mounted high on the lander looking over
the "terrain normalization" mat and one
lens mounted low at the end of a lander leg
looking back at the rover (POV after lander
leg is deployed for landing). All electron-
ics were housed in a 3D printed electronics
bay. Power to the lander systems was pro-
vided by (once again) dual LG BF-45FNV
cell phone batteries. Figure 7 shows the
Mestler lander with its legs stowed in flight
configuration, but without the fabric mat
attached to the legs (since the fabric would
block the view of the interior), and without
the rover in place.
The lander required a total of two pyro
events to achieve a successful landing. The
first pyro event was programmed to occur
32 feet above the ground. The pyro block
assembly is shown in Figure 8. When
fired, an Archetype Rocketry cable cutter
released a tether that simultaneously ex-
posed the lander terrain sensors while also
releasing the six lander legs, allowing the
legs to extend and deploy. Two seconds af-
ter the leg deployment, dual custom mi-
cro timers would trigger to provide current
to a motor driven leg-locking mechanism
(for 8.2 seconds). The second pyro event
would trigger a Tinder Rocketry Tender
Descender to release the chutes from the
lander upon contact with the ground (to