Quadcopter Log, Week 2, Configuration Woes

While attempting to update one of the XBee units to the most recent version of the firmware, I seem to have broken it. I'm not sure exactly how this happened. Previously, I had been using a serial terminal on my mac to change settings using AT commands. This time, I decided to boot into windows and use Digi's official tool, X-CTU. In X-CTU, I changed various settings, including the baud rate, channel, and a couple of other things, and told it update the firmware on the next write. After I wrote the settings to the device, it stopped responding. I tried every solution I could find with google, and nothing has helped. My next step is going to be talking to Digi's support.

I was planning for our first meeting this friday when our president reminded me that it this friday is Good Friday. After sending some emails, it turns out no one wants to show up. So, delayed again...

New Blog!

Capitol College's IEEE Student Branch's New Blog

This is the first post on our new blog. w00t! Nothing much to say.

The blog was created today, 'earlier' posts were edited so they would appear to have been posted when the relevant events occured.

Quadcopter Log, Week 1, Package Time

Parts arrived. One of the IMUs was missing. I contacted SparkFun and they're sending a replacement. I did lots of soldering.

I connected the XBees to my computer using the USB dongle. XBee's are interesting and powerful devices. We're using the Series 1 module, which can do point-to-point, point-to-multipoint, or peer-to-peer. For now we're just using point to point. Using a AT command (via serial terminal), I set the network identifier to 1618 and left the channel at 0x0C. I set the local (controller) module's MY to 0 and DL to 1. I set the remote module's MY to 1 and DL to 0.

Using an Arduino, I established wireless serial communication between my computer and... my computer! Albeit, two different serial terminals on my computer. It's pretty neat.

Over the next week, I'll work more with the XBees and possibly the other components. There won't be a work day this week because of a school function.

Quadcopter Log, Week 0, The Proposal

To get funding for this project, we have been required to log our progress. This is what occurred before building.

So, at the new ideas meeting, we talked about making a quadcopter. Part of the purpose of these projects is to provide interesting and instructional activities for members. As such, I thought we should build our quadcopter from scratch. Searching google for 'diy quadcopter', I came across this. While it is technically a DIY build, it's more like a kit than I want. So I started thinking about what we would need to build our own quadcopter. Obviously, propellers, motors, and a chassis; having no reason not to, I added the ones from the oddcopter.com guide. Other than that, I figured we would need:

• Remote Control - we have various microcontroller systems
• Local Control - no reason not to use a computer for now
• Communication - XBee radios are feature rich, Series 1 is suitable for our purposes
• Stability - an inertial measurement unit, aka a gyroscope and an accelerometer
• Power - a lithium ion polymer battery should work

I decided to add a second IMU and a couple of joysticks for a possible hand-held controller, the idea being tilting the controller tilts the copter. Also, we need a board for computer-to-XBee, a XBee breakout, a lipo breakout/charger, and a couple of motor drivers. The final parts list:

• HobbyKing.com

  • Turnigy H.A.L. (Heavy Aerial Lift) Quadcopter Frame 585mm
  • [4] D2830-11 1000kv Brushless Motor
  • Slow Fly Electric Prop 9047R SF (4 pc Right Hand Rotation)
  • Slow Fly Electric Prop 9047SF (4 pc)

• SparkFun.com

  • [2] Triple Axis Accelerometer & Gyro Breakout
  • [2] XBee 1mW Trace Antenna - Series 1 (802.15.4)
  • XBee Explorer Dongle
  • XBee Explorer Regulated
  • [2] H-Bridge Motor Driver 1A
  • Polymer Lithium Ion Battery - 6Ah
  • Power Cell - LiPo Charger/Booster
  • Thumb Slide Joystick
  • Thumb Joystick
  • Breakout Board for Thumb Joystick

Now we just need to wait for parts (we got approval contingent on weekly blog posts).