Shrediquette stands for multirotors, innovation and FPV since 2008.
Tilted body race quad update 1
Get link
Facebook
X
Pinterest
Email
Other Apps
-
Here are some more renderings of my latest project. I'll write an article on multirotor racing aerodynamics soon, then you'll hopefully agree that this design makes sense ;-D
Its about time!!!!! I have designed a few tilt body, tilt rotor, tilt ed in wing. Nice to see. I have to say disability is all that is preventing mine from taking shape. But in 2017 I too will build a proper quad. Contacts!!!
The last nights were a bit shorter for me, since the PCBs I ordered at bilex-lp.com arrived. They look really good and seem to be of high quality (I ordered a different "solder resist" colour, well, I like bright colors, but anyway... ). So I had the opportunity to do my very first SMD solderings. This really seems to be comfortable... I will completely switch to SMD I think. The I²C to PWM converters work! Here are the features: Weight under 1 g Works with (most likely many) standard ESCs (currently tested: HK SS 18-20A, ...) I²C address selectable via solder jumpers (4 standard mikrokopter addresses dec 82, 84, 86, 88) Refresh rate selectable via solder jumpers (417 Hz, 292 Hz, 155 Hz, 49 Hz) Pulse width (I²C 0-255): 990µS - 2010µS Pulse width at startup (3 s): 920µS Motor off when no I²C connection longer than 256ms Motor off when microcontroller crashes (veeeery unlikely) Powered by the BEC of the ESC, or by an external 5V source (prepared as well) Very eas...
Why future racing copters really should look different. by Dr. William Thielicke aka Willa aka Shrediquette ABSTRACT In this article I try to demonstrate why FPV racing multirotors need to look different. Some small modifications to the frame would (in theory…!) result in 70 % higher top speed! All that needs to be done is to align the arms parallel to the propeller flow, and to tilt the main body of the copter by about 40 degrees. I am presenting a very simple and robust racing copter design that incorporates these ideas. Furthermore, I am calculating the aerodynamic drag of different copter concepts using basic equations. The aim of this article is to make you realize the importance of aerodynamics and to stimulate people to design more innovative racing frames. INTRODUCTION Until recently, multirotors were mainly used as a “hovering device” and the top speed of these copters did hardly matter. Now, multirotor racing has become popular and all competitors are seeking ...
This is my latest 15 inch ultra-long range setup with 50 minutes flight time: Propellers: 15x5.5" Tarot with custom hub Motors: T-Motor MN3110 470 kV Frame: 240g custom carbon structure Lipo: 2x 4S 4000 mAh SLS 20C (parallel) Camera: Micro Runcam micro sparrow Firmware: INAV FC: Holybro Kakute F7 ESC: Tekko32 F3 GPS: BN-180 Compass: QMC5883L Receiver: FRSky R9 slim+ Hovering flight time is 50 minutes at 8.5 Amps and 40% throttle. Current goes up to 12 A when flying 50-60 km/h. Flight characteristics are really good when tuned properly (you'll nee a HUGE D-term). Here is the CAD file of the frame. INAV 2.4.0 PID settings: set mc_p_pitch = 85 set mc_i_pitch = 60 set mc_d_pitch = 150 set mc_p_roll = 85 set mc_i_roll = 60 set mc_d_roll = 150 set mc_p_yaw = 200 set mc_i_yaw = 70 set mc_p_level = 40 set mc_i_level = 10 set max_angle_inclination_rll = 500 set max_angle_inclination_pit = 500 set dterm_...
Summary: FPV racing multirotors with side force generators (SFGs), will drift less during turns, making them potentially faster on race tracks (watch the video comparison here ) . But the SFGs need the be carefully placed and dimensioned, so that aerodynamic centre and centre of mass are at the same position. Otherwise it will not work. Introduction Recently, I was thinking about how to improve the handling of racing copters. I noticed since quite a long time, that different copters behave quite differently in fast turns: Some drift quite a lot (especially when they carry a larger battery or an action cam), others drift less. I was always preferring copters that drift as little as possible. That is also why I am trying to reduce the weight of my copters as much as feasible. The amount of drift depends on the weight of the copter and the lift and drag of the fuselage for sideways air streams (side-slip). The larger the lift and drag, the more side force the fusel...
I added a GPS module, a compass and a pressure sensor to my tricopter to enable automatic position hold. GPS is implemented using a PD control loop, compass is P only, and height is PID. And... it works! Still not optimal, but in principle it is already ok. There are some things that have to be optimized of course, e.g. a one-axis compass will probably not work for waypoint navigation and position hold when there is wind. And my code is still far from being optimal. At the moment, I have to make my copter hover at the position + height that I want. Then, I flip a switch (connected to channel 6) - current position, heading and height is stored and used as setpoint for position hold. I think I will have to switch to a 3-axes compass in combination with an additional 3-axes accelerometer. That will enable tilt compensation for the compass, as well as improving the D-term for height stabilization. The tests that you see in the video where done with no wind at all. The tricopter stayed mo...
Its about time!!!!! I have designed a few tilt body, tilt rotor, tilt ed in wing. Nice to see. I have to say disability is all that is preventing mine from taking shape. But in 2017 I too will build a proper quad. Contacts!!!
ReplyDelete