It's been a while...

Well,
After flying the balloon I took the completed project to the regional Science and Engineering Fair here in Albuquerque. After competing there and at state competing, I qualified to go to the International Science and engineering Fair (ISEF) in Indianapolis, Indiana. This is a big event. I mean HUGE. There are almost 1500 projects from 40 different countries. I think the total prize count came to about $3 million. Besides the prizes, the budget is around $4 million. Here is a picture of the hall before the projects were all set-up. The picture shows half of one row, which was only a fraction of the 1500 projects.

This is my project once it was set-up. For the duration of the fair you are locked into a small 5 by 5 foot cell with your project to be questioned, criticized and harassed.


If you think you have seen a lot of people in on place before, imagine 900 judges, 1500 fair participants with a sponsor or tow each and a flood of press members all crammed through the one entry area into the project area.


After the nine hour ordeal that is judging at ISEF, you are rewarded with the largest spectale in awards ceremony known to modern man. I managed to receive a fourth place award in engineering, which, for an international fair, isn't bad.

Video Link

Here is the link again for the video:
http://video.google.com/videoplay?docid=-7963224333147032144&q=XRB&pl=true

If the link doesn't work, you can search "XRB" In google video

The first Automated Flight

About a week ago the balloon flew its first through seventh automated flights. It has been very windy here in Albuquerque, so the flights were flown inside a basketball gym. The balloon, using the software I wrote, was able to ascend to 130 inches, then begin its descent. All seven flights did have bounces upon landing, but some fine tuning of the software was enough to make the bounces smaller. The flights were by no means perfect, but they are a large step toward the completion of this project. Next I plan to fly the balloon outdoors, where it will be able to use the GPS reciever and achieve higher altitudes.

*I am trying to figure out how to post videos, and when I do, there will be one here. If you know how, please give me a comment about it. I can delete it later.*

An update.... Finally

I have finally had the time to make a blog entry, so here is an update. I have received the envelope and frame, and built the basket up quite a bit. I have added a basic stamp, a wireless receiver, a ultrasonic altimeter, and a camera. I will fill you in on the details later, but for now, here are some photos:

An update.... Finally

I have finally had the time to make a blog entry, so here is an update. I have received the envelope and frame, and built the basket up quite a bit. I have added a basic stamp, a wireless receiver, a ultrasonic altimeter, and a camera. I will fill you in on the details later, but for now, here are some photos:

Electronics Construction

I have begun work on building the electronic controls for the XRB Alpha. I have built both the controls to be placed in the basket, and the ground controls which will allow for manual control if necessary, and also as a link to the laptop computer.

For the ground controls, I gutted an old Black and Decker case. The antenna sticking out of the side is for the wireless camera( see wireless camera below below)


Here are some photos of the inside of the Ground Control Box:




Here is the Balloon Control box, complete with BASIC STAMP and wireless link to the ground control:



I also built a small device to drop something out of the balloon. The servo operates a piece of fish line, which opens the compartment and drops its contents. I have tested it successfully several times:



Here is a photo of the wireless camera I plan to mount to the balloon. It is just about 3/4 of an inch across, and ways very little:

Actual Plan

I have written a proposal which I have given to some of my potential sponsors. Below is a copy of the relevant parts. I have also named the Balloon The XBR Alpha, for Experimental Robotic Balloon Alpha.



Goal-

The goal of this project is to design, build, and test an automated hot air balloon. The balloon will be able to take off, fly, and land on its own. It will also be able to chart its own path, and eventually, predict landing locations. A laptop computer on the ground will be able to track the balloon using a program created in LabView.


Construction-

The balloon envelope will be constructed from 3/4 oz rip stop nylon, using 12 vertical gores, and one horizontal panel. The fabric is cut into gore shapes, then sewn together to form the entire envelope. The top of the balloon is attached with Velcro, so it may be removed to deflate the balloon. Load tapes, cords running down the balloon to lessen pressure on the fabric, are added. The basket is attached to these cords. The basket is constructed from aluminum, and carries all the controls for the balloon. Normally, the basket carries propane fuel, and a burner. The burner operates by first vaporizing the liquid propane, and burning the vapor to create an intense flame. In addition to these devices, the XRB Alpha will also carry electrical equipment to control the balloon. The heart of the electronic controls is a BASIC STAMP, a small, low power microcontroller that controls the other elements of the balloon. To start, the STAMP will control the burner via a binary servo valve, located in the basket. The STAMP may also eventually control the deflation valve. In addition, the STAMP will also gather information from an array of sensors, including a Global Positioning System (GPS) receiver, an anemometer, ultrasonic altimeter, ground contact sensor, and flame sensor. The role of these sensors is explained under “Flight”. The balloon will also be equipped with a two way serial radio for communication with a laptop on the ground.

Flight-

The balloon will be inflated with cold air by hand while it lies on the ground. After it has been inflated, an initial, human controlled firing of the burner (or burn) will take place. This will heat the air inside the balloon so that it rises to an upright position. Control is now switched over to XRB Alpha by turning on the control systems. The BASIC STAMP will initiate all of the required sensors, and confirm that the ground contact sensor is tripped. The XBR Alpha will then initiate a burn, until data from the GPS indicates that the balloon is rising. Following a preprogrammed flight plan, the

XRB Alpha will achieve a desired altitude, as measured by the GPS, and then begin its descent. To descend, the XRB Alpha will execute fewer burns, allowing the temperature in the envelope to fall, and in turn, allowing the balloon to descend. The BASIC STAMP will ensure that the balloon does not fall too quickly by taking readings from the GPS. The balloon will rely on the altitude given by the GPS until the ultrasonic altimeter detects that the balloon is 9 feet above the ground. The ultrasonic altimeter is necessary because the accuracy of the GPS is not accurate enough to determine the balloons altitude within this distance. Once the BASIC STAMP begins taking readings from the ultrasonic altimeter, it will slow the descent until it detects the ground via the ground contact sensor.

Laptop-

Throughout the entire flight, the XRB Alpha will be in contact with a laptop computer on the ground via a wireless serial radio. Through a program created in LabView, the user will be able to monitor the altitude, location, horizontal and vertical speeds, wind speed, and eventually, a video feed. The laptop will also provide a way to control the balloon manually, in the event that it is necessary.

First Inflation!!

Tonight I inflated the balloon for the first time. It inflates really fast. I have not yet built in a deflate valve, but that will come. Tomorrow, I am going to pull out my welding torch and see whether i can get it to actually left off the ground, until then, this is all i will be able to do.

Sewing

Today, I began and finished the process of sewing the gores together. Here are some photos of me sewing:


•Sewing with my singer


•Hear is a finished seam

It took a little fiddling with the machine to get a good a good seam. If the stitch length is too long, the seam will no hold the fabric together, if it is too short, the nylon thread will gum up the needle. Eventually, I got it right. That's what scraps are for!