After a month-long hiatus after the crash, I redesigned the tricopter chassis. The aluminum arms are now foldable, and the motors are closer to the center of the chassis (I have yet to trim the arms to a shorter length). There is room for the new and bigger ESCs underneath the other electronics.
On August 1, we (the OSU Autonomous Aerial Robotics Team) will compete against 27 other collegiate teams from around the world in the 2012 International Aerial Robotics Competition. The current (6th) mission of the IARC requires teams to develop an aerial robot capable of autonomously navigating an indoor space (i.e., hallways, furnished rooms) to locate [...]
This is mainly for my record. Of the three Red Brick 70A ESCs I ordered from HobbyKing to replace my burnt-up ones, one had different pin assignments to the FETs than the other two. This required me to upload the rb50a firmware instead of the rb70a. Before I figured out that the rb50a firmware worked [...]
Actually, I don’t really know how other than to build a tricopter as awesome as mine. Earlier last month, I flew my tricopter up to about 80 feet above the ground to test its range as well as controllability. Due to a shortage of my usual propellers, I had been flying with an oversized tail [...]
Or, the best one-line bug fix ever. For two months, I had been thinking I was running my flight controller at 166 Hz while actually running it at a measly 31 Hz. I don’t want to go into detail about how that happened, but I have fixed the problem, and now it works. I am [...]
Some systems can be controlled with a simple P controller, where a given offset is translated directly to some actuator output. Other systems, like the flight orientation control of micro aerial vehicles (MAVs), may require a damping term on the position to prevent a divergent oscillation of the vehicle’s angular position. However, the D controller [...]
Multirotor flight control requires an update frequency on the order of hundreds of cycles per second. Most ESCs sold for RC plane use are capable of reading a PPM input at frequencies of up to 400 Hz, but they do not translate the PPM input to motor speed output at the same rate. tl;dr: Flash [...]
Two years ago, I designed my own motor driver breakout board using two L298N motor driver ICs and had them manufactured through BatchPCB. Here it is, finally finished. The KiCAD files are on my github repo here.
Sensors are cool, but the really cool ones come in tiny packages that require breakout boards to be easily usable. I often buy (populated) breakout boards from one of the many hobby electronics vendors out there, but they are often in the $20 to $60 range (like this LSM303 breakout board), which is rather prohibitive. [...]