As discussed in the white paper
, the aim of the blimp UAV project is to build a prototype for an indoor aerial robotics contest. This will require contestants to design, build and program a blimp that can navigate a course inside a gym-sized space and potentially do certain tasks such as spotting targets and landing at intermediate points.
To do this, our blimp has to be able to know its current position in six degrees of freedom: x, y, z, yaw, tilt, pitch. This is hard enough outdoors, but it's especially tricky indoors, where GPS doesn't work. So what we're planning is a blimp with the following components, including a cool IR beacon-based system (shown) to simulate GPS:
- Blimp: BlubberBot envolope (46"), which can carry a 125 gram payload
- Inertial sensors: two-axis accelerometers for tilt and pitch, magnetometer for yaw.
- Position sensors: Evolution Robotics NorthStar system, which uses stationary IR beacons in the room as reference points (not unlike the way a Roomba makes its way back to its charging station)
- Altitude (Z) sensor: untrasonic sensor with 3-meter range
- Three motor system (differential thrust for left and right, and one for up/down), like the Plantraco Microblimp
- CPU: Undecided, but may well be Pic-based.
- Usual I/O, including serial/USB for programming and a servo controller for at least two micro servos (use to be decided)
- Power: 200 mah LiPos (5.4 grams)
- PCB: Approx. 1x1.5 inch board (1/32” thickness for weight savings)
- Programmable in RobotC
Seems very doable within our weight limit. Next step: CPU selection and building a breadboard prototype with the NorthStar board.