speech

HLOs - how affects
	- Autopilot is the subsystem actually controling the blimp. It is necessary for having an automated system.
System reuqirements + rationale
	- Q, R, S, T
subsystem architecture
	- IMU - measures accelerations and angular velocity; computes position and velocity and such
	- guidance computer, responsible for waypoint generation, control laws
trade studies
	- considered four computers, two IMUs
	- wanted linux, 9dof
	- selected BeagleBone computer, and ArduIMU+ V3
interfaces
	- power - 5v, several watts
	- proximity sensors - software interrupt
	- interface with other subsystem programs - dbus
	- telemetry - D-bus
	- propulsion - D-bus
	- airframe - tape + padding for imu, GC in gondola
	- image processing - input position vector via dbus
	- 
preliminary design
	- IMU connected to BeagleBone via UART; imu tx -> beaglebone rx
	- IMU has an integrated 3axis accelerometer + gyro, and a magnemtometer chip, with an atmega 328 MCU
	- extended kalman filter on IMU MCU, printing to serial
	- gc runs angstrom linux, may change to gentoo or ubuntu
	- finite state machine on gc, changes states based on operating mode
	- fsm generates different waypoints for each state
	- passes waypoint, kinematic state to velocity calculator
	- creates estimated trajectory, solves for velocity and thus force using optimisation theory
	- pid controllers to act on output force