Gender
Male
About
Location
Nashua, NH
About Me:
Many years ago I used to build my own autopilots from scratch as a hobby. Now I work full time in drones at CyPhy works!
Please tell us a bit about your UAV interest
Miss the days when you had to make your own autopilot from scratch with no open sorcery. Now everyone seems to be in the club!
Hometown:
Nashua, NH
Activity Feed
10 years ago I was flying and posting videos here developing my own autopilots and autonomous vehicles. Eventually this lead into a full time career in drones and ultimately landed me here at CyPhy works! Maybe others out there want to do this for a…
"I wouldn't discount the idea. I had my IMU in a wingtip and the accelerometers worked. I bet as accels get lower in noise, you may start to get useful rotation data-- where one wingtip accelerates up and the other down. I think the idea is sound,…"
"PS - What did you wind up using for your photo stitching if you don't mind sharing?"
"@Krzysztof - Been watching your progress for a year or so. Congratulations! I have yet to really do much with my tech, and haven't really found anyone willing to take a risk here in the states given the regulatory situation. Did you partner up with…"
"Wasn't space 50k feet less than 100 years ago? Then they moved it to 50 miles. Now it's 62. Balloons reach what is commonly called "The edge of space" by the various groups. I like that title better."
"http://bordelon.net/radioflier-1.html
It is legal, part 101 FAA regs.
I wish I had an HD camera in 1998! This video kicks butt."
It is legal, part 101 FAA regs.
I wish I had an HD camera in 1998! This video kicks butt."
"@Ritchie - Yep, there are 3 or so versions of that camera. I am able to set the time, but every time I hook it to the PC it resets. Thanks for the encouragement. After a crash I get depressed for a few days. I shall return!! (I guess it happens to…"
"And more good stuff. http://www.aerospaceweb.org/question/performance/q0146.shtml"
"I definitely have more reading to do. According to this book, "Principles of Flight Simulation", section on heading hold, they do exactly what you suggest. BUT- they use AIRSPEED and no atan:
bank angle = (turn_rate*V) / g
This of course seems…"
bank angle = (turn_rate*V) / g
This of course seems…"
"Maybe the answer is this: The inner loop, the turn rate command, is made to be independent of SOG with Ryan's formula. This loop most likely settles faster than the speed we encounter new bearing vector commands. So I suppose in my example, the…"
"Okay, what about this problem :)
The solution presented here makes the turn rate the same no matter what the airspeed, which sounds good at first. But imagine the aircraft is traversing a vector field made up of a grid of vectors. It takes the…"
The solution presented here makes the turn rate the same no matter what the airspeed, which sounds good at first. But imagine the aircraft is traversing a vector field made up of a grid of vectors. It takes the…"
"@Mikko - I totally agree with Ryan as it relates to trying to fly exact paths on the ground. But as far as airspeed goes, the other issue is limiting your bank angle so you don't bank so much that you cause a stall."
"@ryan - that graph proves my point. Stall speed increases with bank angle. So you have to adjust the bank angle limits as airspeed decreases."
"One question remains: It makes sense to me to do this based on ground speed. But you don't want to bank too steep at lower airspeeds, which this doesn't really address. Perhaps an additional step of limiting bank angle in the same way based on…"
"@ Ryan - Found your paper http://dl.dropbox.com/u/2884350/Improved%20Heading%20Hold%20Control... to be quite awsome.
This morning my idea was to simply scale the bank limits and gain by v^2, but the added atan() drives it home. I will probably do…"
This morning my idea was to simply scale the bank limits and gain by v^2, but the added atan() drives it home. I will probably do…"
"@Ryan - Ok, you're the man. Your video completely explained the problem to me as well as the solution. I love the idea of linearizing the output. IE - We want to command a turn rate, so take the turn rate and run it through the usual aero formula…"
