It just came to my attention that people trying to use the latest revision firmware with the older ArduIMU hardware were having problems. The current revision firmware has lots of goodies in it that the pre-v2 hardware firmware did not have such as much better vibration resistance, euler angle output, binary message output for Ardu-IMU-Pilot, etc. We had included code in recent revisions to allow use of either hardware, but I guess neither Jordi, Jose, or myself had checked it on the v1… Continue
The civilian version of the Osprey V22 tilt rotor is the TG-609. Such a vertical take off, fixed wing flight platform has long been a UAV dream, but it's proven too tricky for RC modeling to date. Now Gaui seems to have cracked the code. After more than… Continue
If you've been following Tom Pyke's progress on his impressive Gluonpilot, you will have seen that he's implementing it with a realtime operating system (RTOS), rather than programming "straight to the iron" the way most autopilots are done, to gain maximum control over interrupts, timing and the like. He's using a relatively powerful dsPIC chip, which can handle the overhead of the RTOS (I think he's using FreeRTOS, but I've…Continue
I was researching prior art for a fully redundant motor/ESC/Battery device, and came across this patent for the the Segway ESC by Dean Kamens group (DEKA). And I realized that given enough money and an interest in a particular field, these companies could patent the obvious and make open source a difficult… Continue
I'm trying to find out what is the maximum update rate for a typical ESC is. I saw that most quad copter designed require the ESC update rate to be very high, i.e 100Hz or more.
My understanding a ESC takes a PPM signal from 1ms to 2ms with a 20ms duty cycle. So a max of 50Hz update rate, is that correct? Is there some "play" in the duty cycle maybe max of 10ms. Or I'm way off base? Looking at ESC data sheets seem to be missing this information.
Just like in the previous version of Ardupilot, throttle control maintains speed and altitude. I've made a little demo to help demystify the behavior of throttle control. This loop uses a special scaling feature that brings up the throttle to a high level when the airspeed dips below the desired cruising speed. Altitude of the plane is also maintained with the throttle by increasing the desired airspeed. Finally airspeed is scaled to match a throttle output %.…
Ardupilot 2.5 has the same heading control as before with the addition of a simple controller to adjust the rate or turn for the rudder. To give you a better tool for setting gains and for understanding what happens where and why, here is a handy interactive version of the PID code.
Mouse the mouse left or right to indicate which direction the plane should be turning. Up and down control the current roll of the… Continue
I thought I would start featuring what's new in 2.5. As you might know it's more than bug fixes. It's an entirely rewritten version that's intended to scale up and be customizable for all sorts of fun things including future projects like Mega. I just finished the loitering code so I thought I'd post that feature first.
On a tip from Ryan Beall, I implemented a simple vector field algorithm that holds the orbit around a… Continue
I ahve been a passive member of this community a while, but greatly inspired by knowledge and igenuity of the members on this forum. I am gearing up to go for Grad school and do MS in Computer Science hoping to specailize in AI. Its been years since I finished undergrad and that was the last time I worked with programing languages. I am now trying to sharpen my programming skills and get them to speed and am wondering which programming language I should develop proficiency in. Iam thinking of… Continue
I finally had some quality time with the Ardupilot Airframe Tester in the air and would like to report, after a few bug fixes and tweaking, I finally have a nice solution.
Why this matters and why you should fly it:
- It will help you set up your plane properly and give you vital debugging information.
- It will help you adjust your stabilization gains
- It is a very nice flight stabilizer
- It will let you test your Autopilot setup (more on this… Continue