Profile

Cover photo
Curtis Olson
Works at Airborne Technologies, Inc.
Attended Globe High School
Lives in Minneapolis, MN
265 followers|730,699 views
AboutPostsPhotosYouTubeReviews

Stream

Curtis Olson

Shared publicly  - 
 
Sea bird off the coast of Oahu.
1
Add a comment...

Curtis Olson

Shared publicly  - 
 
Spring mornings ...
1
Add a comment...

Curtis Olson

Shared publicly  - 
 
Wow, this tutorial couldn't have been posted at a more appropriate time.  I just ordered a new battery and it came with one cell extra low.  It was taking a ton of time to bring the low cell up to balance while the other 2 cells were already fully charged.  This video gives an easy explaination of what's going on under the hood and offers a really easy solution to charging individual cells.  So I'm currently rescuing my new pack (hopefully!) instead of wasting a bunch of time on an RMA.
2
Add a comment...

Curtis Olson

Shared publicly  - 
 
Woo hoo, my first ever self-designed PCB just arrived.  Next up is a small bit of assembly and a huge amount of testing in hopes of not releasing any small mushroom clouds of smoke the first time I power things up!
6
John Anderson's profile photoCurtis Olson's profile photo
6 comments
 
I am doing the sensor fusion on the linux side.  I don't have the algorithm link handy but I can look that up later if you are interested.  The APM just reports raw sensor readings.  In the past I've gotten my boads from 3DR, but they are moving past the APM so the most recent board I bought was from hobbyking.  There were a couple things I didn't like about that, so I might try a "miniapm" from rctimer.com next time.  They also make a gps board with the same form factor so (I think) they should stack.  I don't know anything about the udb5, but feel free to grab the code and do anything with it.  You'll want arduino-1.0.6 to successfully compile it.
Add a comment...

Curtis Olson

Shared publicly  - 
 
Scientific American Reader: Moore's Law Keeps Going, Defying Expectations. http://google.com/newsstand/s/CBIwrIij9R8
2
1
Erik Hofman's profile photoMartin Spodniak's profile photo
 
I believe I read somewhere they are now approaching atom size for control logic, so at some point it will require shift in technology.
Add a comment...

Curtis Olson

Discussion  - 
 
As promised earlier, here is a quick example of IMU temperature calibration fit.  The IMU is an MPU-6000 from an APM2.  The EKF is a 15-state kalman filter published in ch 6-7 here: https://books.google.com/books/about/GNSS_Applications_and_Methods.html?id=juXAE3SHQroC&hl=en

The 15-state EKF does a really good job at estimating both gyro and accelerometer biases.  I added IMU temperature logging.  With that I can go do a flight, collect bias and imu temp data, plot bias vs. temp, and do a 2nd degree polynomial fit.

The result is a bias estimate for the current temperature for each individual inertial sensor (within the range of temperatures where we have previously flown.)

The plots below are were collected by placing the full system in my car and driving for 30-45 minutes with the heater full on, and then later with the windows open to create a range of temperatures.

The idea is that the more an individual system is flown across a broader range of conditions, the more data you have and the better the overall fit becomes.

The filter does a really good job at estimating bias, but pre-calibrating the sensor values for the current IMU temperature means that the filter has a lot less distance to travel for it's initial convergence.  This is useful for things like auto-takeoff where the filter is still establishing a good convergence.

I am also developing a process to estimate scale errors from the flight data.  Scale errors are less observable, but my process so far is showing promise.  The filter is pretty robust to 5% scaling errors though so scale calibration is less of a big deal than you might first thin ... especially for typical uav flying where most of the time the aircraft flies near the sensor zero points.

Oh, and for what it's worth, the values I've derived from the flight data seem to agree pretty well with the values I've determined from a typical manual calibration process.
1
Add a comment...

Curtis Olson

Discussion  - 
 
Here is one more video of a fixed wing autonomous flight flying with the avior-lite (linux based) autopilot.
1
Add a comment...
Have him in circles
265 people
Don Burns's profile photo
Matthieu Laban's profile photo
Reagan Thomas's profile photo
Juan Martín (Nemesio)'s profile photo
Dave C's profile photo
RC Skyhawk's profile photo
Singular Aircraft's profile photo
Claudio Marchi's profile photo
Hoang Sinh's profile photo

Curtis Olson

Shared publicly  - 
 
Taken at Oshkosh.
3
Add a comment...

Curtis Olson

Shared publicly  - 
 
Up and running Fedora 22 here ... so far so good.
 
Fedora 22 Released
We are proud to announce the official release of Fedora 22, the community-driven and community-built operating system now available in Cloud, Server, and Workstation editions. If that’s all you need to hear, jump over to Get Fedora to download —... Continue Reading →
37 comments on original post
1
Add a comment...

Curtis Olson

Shared publicly  - 
 
It's just a very simple beaglebone cape, but I designed it myself, got a prototype fabricated, soldered the connectors and parts on this morning, powered it up, and so far everything is working as designed.  I'm just waiting on two cables now so I can connect in the final component (an APM2) and then the beaglebone will have easy and inexpensive access to a full suite of inertial, gps, temp, barometer, volt, and current sensors as well as be able to control 8 servos and read 8 PWM channels in (i.e. pilot inputs from an RC receiver.)  (The APM2 board is not shown.)

The next rev of this board is already been drawn up ... lots of little tweaks from what I learned on this one, plus some new things I've thought of in the mean time.

The little green board soldered on top is a 4 channel TTL level shifter breakout board from adafuit.  I designed the board so it could be assembled by someone (like me) with just barely enough soldering skills to attach 0.1" headers.
4
Michael K Johnson's profile photoCurtis Olson's profile photo
12 comments
 
Stiff wiring is a good term for what I'm doing. Seeed studio seems like it could be a pretty good deal.  I found a piece of software that claims it can import express pcb and output gerber ... hope I can find that again someday ... something like "copper connections."  Otherwise, it probably wouldn't be too hard to start from scratch in another tool if I've already worked out exactly what I want.  I appreciate the feedback and tips.  I really would love to learn more of the low level stuff, but my brain can only absorb so much so fast.  It seems really clunky to solder a breakout board to my board with 0.1" headers, but for now it should hopefully work and will be a whole lot better than the rats nest I have sitting on the corner of my desk right now.
Add a comment...

Curtis Olson

Discussion  - 
 
Quick clips from 4 autonomous takeoffs in a Senior Telemaster.
3
Add a comment...

Curtis Olson

Discussion  - 
 
I'm working on a beaglebone cape that will interconnect an APM2 Mega (or Mini).  The idea is to keep it simple and maximize existing off the shelf components.  The APM2 is the sensors for the beaglebone.  The APM2 runs a special custom firmware that does all the sensor interfacing, reads the RC receiver, and drives the servos.  The beaglebone is then freed up of all the hard-real-time responsibilities of sensor IO and it can focus on running an advanced EKF and all the other higher level autopilot, navigation, mission, and task code.  I have a flying prototype so now I guess it's time to make some hardware.
7
Ryan Upton's profile photoJohn Anderson's profile photoCurtis Olson's profile photoMichael Thomason's profile photo
5 comments
 
Very cool.
Add a comment...
People
Have him in circles
265 people
Don Burns's profile photo
Matthieu Laban's profile photo
Reagan Thomas's profile photo
Juan Martín (Nemesio)'s profile photo
Dave C's profile photo
RC Skyhawk's profile photo
Singular Aircraft's profile photo
Claudio Marchi's profile photo
Hoang Sinh's profile photo
Collections Curtis is following
Places
Map of the places this user has livedMap of the places this user has livedMap of the places this user has lived
Currently
Minneapolis, MN
Links
Contributor to
Work
Occupation
Flight simulation and embedded avionics engineer. (and UAS test pilot.)
Employment
  • Airborne Technologies, Inc.
    Embedded Avioinics Engineer, UAS Designer, Chief Test Pilot, present
Education
  • Globe High School
    1982 - 1985
  • Bethel College
    Computer Science Major, Math Minor, 1985 - 1989
  • University of Minnesota
    Computer Science, M.Sc., 1992 - 1996
Basic Information
Gender
Male
Best and largest apple fritter we have ever eaten.
Public - 10 months ago
reviewed 10 months ago
Wow! A great, world class, live magic show and kid friendly too. Our kids have seen local magicians do a few tricks at school or the fair, but never anything remotely close to this and they were completely blown away. Highly recommended, and one of the first places we'll visit again when we go back to the Dells.
Public - a year ago
reviewed a year ago
Wow, this was the best ice cream we have had in a long time! Enough said!!!
Public - a year ago
reviewed a year ago
Carvelli's was a really pleasant surprise for us. They offered really great service, the chef rocked, and the food was wonderful. This was definitely the best restaurant we visited during our 4 days at the Dells. Our vacation at the Dells was marked by some big hits and some big misses so we weren't quite sure what to expect walking in off the street. Carvelli's is right at the top of our family's "hit" column. If you are looking for a place with some character and class (that isn't just another chain restaurant) definitely put Carvelli's towards the top of your list of restaurants to visit while you are staying at the Dells! Here's a quick parking tip: the main street through the downtown dells area is all parking meters, but if you turn off on a side street (like Cedar) we found it really easy to find a free spot just a half block off the main drag.
• • •
Public - a year ago
reviewed a year ago
9 reviews
Map
Map
Map
I wish we would have read the reviews here before we went. They have a beautiful outdoor patio and we visited on a perfect evening for sitting outside. But everything others here have said about the food rang true for us. When they brought out our dish of butter packets, there was some used chewing gum stuck to the top of one of the packets. That grossed us out, but it's an honest mistake if the dish was recycled from another table and we were willing to forgive that. But then my daughter's hamburger was really under-cooked and things just didn't improve from there. It's a beautiful place so I wish I could write a better review ... maybe on a different night if we ordered different things it would have been better?
• • •
Public - a year ago
reviewed a year ago
We just wandered in on a whim because we pretty much made it to the end of the whole downtown stretch and hadn't found anything else the kids were willing to eat. We had a great experience. The prices were very reasonable and the food was really tasty -- and the service was also very good. We would definitely eat here again next time we visit the dells.
Public - a year ago
reviewed a year ago
Public - a year ago
reviewed a year ago