|RGB LEDs are mandatory on some events...|
|Increased camera angle. The ultra-large capacitors |
might keep my ESCs and motors from dying all the time
(I lost 4 motors due to ESC malfunction already). I also added a
pull-down resistor (10k) to the signal wire of each ESC.
|Pushbutton for channel selection & integrated power plug.|
|'Last christmas, I gave you my....'|
Roll_output = cos(camera_tilt) * Roll_input - sin(camera_tilt) * Yaw_input'camera_tilt' is the angle (in radians) that your FPV camera is tilted up with respect to the propeller disks. It is a constant. I am using 25 degrees of camera tilt (= 0.436 radians).
Yaw_output = sin(camera_tilt) * Roll_input + cos(camera_tilt) * Yaw_input
|DERBE mounted inside the wind tunnel|
|Particle image velocimetry: Setup consisting of high-power laser, high-speed camera and particles in the fluid.|
|PIV measurement with a laser sheet|
|Top view of a multirotor. The green lines show the locations where flow velocities were determined.|
|This image sequence shows the laser sheet in position B.|
|PIV measurement around the main frame (position A): The flow is mostly horizontal in this plane.|
|Measurement position B: Only the blades that move forward through the plane (= the front propeller) generate thrust.|
|Multirotor in fast forward flight: The green areas create most lift, parts of the red areas might even create drag.|
Note that this is only true for the propeller rotational directions shown in this image. If all propellers
rotate in the other directions, then red and green areas need to be inversed.
|Do vertical arms make sense...? Not really...|
|Shrediquette 0815, a standard racing quadrotor that I designed for training and to learn more about|
lightweight and rigid plastic construction.
|Usually, the flow is perpendicular to the propeller disk. |
The faster a propeller turns in relation to the flight speed ("advance ratio"),
the more constant is the angle of the flow.
|The main body of the Shrediquette DERBE is tilted by 40 degrees.|
|Three different concepts: Comparison of frame area (green) |
and area of the arms under the propeller (blue).
|Standard racer||Shrediquette QRC5||Shrediquette DERBE|
|Max. tilt angle [deg]||38||29||34|
|Top speed [km/h]||107||178||170|