Thursday, November 18, 2010

Norridgewock aerial survey

Tucker and I completed an aerial survey of a mitigated wetland area in Norridgewock, ME this past summer. We used the 2 pound WASP UAV to fly over the survey area while capturing images from around 500 feet above ground level. Here are a few stand alone images we captured. We will be uploading the entire photo mosaic shortly which we hope can be used as a base map for future biological research missions.

Saturday, June 26, 2010

Wasp UAV Testing

Here's a video from Wasp UAV testing. Now that the control surfaces (elevons) are trimmed we will start integrating the autopilot. Stay tuned for updates.

Wednesday, June 23, 2010

"Wasp" Airframe

Over the past few days Dan and I built our new UAV airframe dubbed the "Wasp." We chose the EPP foam Zagi XS flying wing as our new platform because it's designed for beginner pilots and has a small wingspan (48''). We hope this combination will enable beginner pilots to operate the UAV more easily - with less damaging crashes and more successful flights.

First we began by gluing both wings together with 3M-77 Spray adhesive. This adhesive is both lighter and stronger than the hot glue we used on airframes in the past.

Next we inserted strengthening spars in both sides of the wing and fuselage. These spars make the flying wing more rigid and resistant to bend during high G forces. We placed ten pound weights on each side to ensure it held its aerodynamic shape through the drying process.

After spraying down the foam with adhesive, we applied the thin colored packing tape. The contrast between the black and yellow should help with visual orientation when the plane is in the air. We then installed the provided plastic fuselage covers.

We attached the two elevons (control surfaces) using PVC tape hinges. The servos for these hinges are imbedded in the wing.

Wasp UAV: Stats and packing list

Wing span: 48''
Wing area: 2.8 sq ft
Wing Loading: 8.75 oz sq ft
Servos: HS-81 Hitec
Motor: Grayson Hobby Micro Jet V3 Brushless Outrunner
Battery: 1000 mah Zippy Lithium Polymer
Speed Controller: 20 amp Super Tigre Brushless ESC
Parachute: Red Arrow Hobbies 30'' diameter
Autopilot: Attopilot V 1.9
Receiver (Rx): Spektrum AR500
Transceiver (Tx): Spektrum Dx7
Camera: FUJIFILM - FinePix 10.0-Megapixel Digital Camera

Wasp UAV: Component weights

Plane: 16.05 oz

Camera: 4.5 oz

Autopilot and sensors: 3.8 oz

1000 mah lithium battery: 3.17 oz

Parachute: 1.2 oz

Total: 28.72 oz

We will be testing the new airframe and once we're operational we'll be flying several missions for Colby professors involved in research around the Belgrade Lakes Watershed. Biology professor Cathy Bevier, who has generously funded this latest airframe build, has asked us to create a high resolution map of a mitigated wetland area in Norridgewock where she is conducting research. We're also working with Professor Jim Fleming, the project's conceptual advisor and honorary flight crew member, to provide images of other areas pertinent to the Belgrade Lakes project.

Thursday, May 13, 2010

Crash Test with Fail-Safe

Yesterday we tested the fail-safe parachute a few times and it worked well - reducing the planes crash velocity significantly. This was our first crash (out of many over the past 8 months) which left the ready to fly after wards. Video below.

Sunday, May 9, 2010

Fail-safe parachute test

Today Tucker and I tested our 30'' nylon fail-safe parachute on the Manta airframe at Colby. The idea here is that we can remotely release the parachute while the plane is crashing. Once released the parachute will slow down the plane and we'll be able to land it safely. Here's a video of an initial test.