RC Blimp to Autonomous Blimp

Hello Everyone,

I have a remote control blimp, and I want to make it into an autonomous robotic blimp. Currently, there are 3 servo motors on the gondola of the blimp. I plan on putting a whole bunch of sensors on there too (either IR, or ultrasonic). I am also hoping to just put a simple transceiver on the blimp, that will send the sensors’ measurements down to the ground station (that contains the PIC, transceiver’s pair, and PC - for real-time control if needed). To me, that is the most flexible system for a sensor platform. I want the whole thing to be flexible, because I’ll be experimenting with different sensors, such as optical flow (I will try and take the optical flow sensor from the mouse, and put a camera lens on it).

I’ve already decided that for the transceiver, I’ll be using the SFE - RF Link - 2400bps - 315 MHz device,or theSFE Transceiver MiRF - Miniature RF 2.4GHz (since it’s smaller). Which one will allow me to connect more sensors (I only need one pin per sensor output, I think), if I want say… 4 sensors - 4 analogue outputs coming from the blimp, to the ground station?

Also, I still need proper control over the 3 motors - ie, a motor controller. Although I’ve built a simple H-bridge, that only offers me control over two motors - not 3. So I was wondering if I would require something like the Pololu Micro Serial 8 Servo Controller? This seems to be ideal for my application of having an “as light as possible” blimp, while allowing me to control 3 (not 2 - otherwise, I’d have considered the Pololu Baby Orangutan Robot Controller B-168) servo motors. Or is there some simple solution that I’ve completely missed?

Cheers

For the RF link, you will need a PIC on both ends. In the blimp it will collect sensor data and push a data packet through the transmitter to your ground station. Once the ground station receives the data packet, the ground station PIC would decode it and either display the information for the operator, or act upon it by sending a command packet back to the blimp’s PIC. The blimp’s PIC could in turn send commands to the 3 servomotors directly, without the necessity of an external servo controller. There are many ways to go about this but the neither of these RF products offer analog inputs. Some of the higher end RF products we offer have this functionality though.

If you didn’t take apart the blimp, try to measure the current each motor requires when in operation. There might be a chance you can use PWM pins directly (sans motor controller), saving you weight and cost. The Pololu Micr Dual Motor controller is about the smallest I have seen on the market unless you make your own PCB.