Chassis' locomotion system is driven by two electric
scooter motors, geared to give him a top speed of about 3
MPH, or slightly slower than a person can walk. Two 7 AH 12V
AGC sealed batteries power his drive system and
electronics. Chassis' motors are variable-speed and
independently reversible, allowing him to move backwards,
forwards, steer, and even spin in place. Two casters in
addition to the two drive wheels give Chassis a stable
base. All motors, power electronics, and batteries are in
Chassis' black base, giving him a low center of gravity and
leaving his torso free for the beverage system.
Radio control commands generated by a
VEX
remote
controller on RC ground channel 89 (75.970MHz).
These are are decoded by a custom AVR Atmega-8
microcontroller board to generate motor drive and interface
commands. Motor speed controllers are rebuilt IFI Victor 884
speed controllers. (These were scavenged from a local high
school
FIRST Robotics
team who fried them in competition, and rebuilt with
new drive MOSFETs.) Additional remote channels control left
and right eyes for winking and blinking, as well as Chassis'
head propeller, and the beverage delivery valve.
A 5.8 GHz cordless phone was adapted into a wireless
intercom, allowing the remote operator to speak through
Chassis' front speaker as well as listen from a
microphone. This allows Chassis to be fully interactive and
display his distinctive personality.