Differences

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--- rc:3s-quadcopter [04.12.2011 21:57]
vergo [Software setup]
+++ rc:3s-quadcopter [01.03.2015 20:39] (current)
vergo
@@ Line 1: / Line 1: @@
+~~NOTOC~~
+<note important>This quadcopter was dismantled on 1.3.2015 after 76 flights having served me well as a learning platform for both LoS and FPV flight. The last flight can be viewed [[https://www.youtube.com/watch?v=VpSk6reU2yQ|here]].</note>
 ====== 3S Quadcopter ======
@@ Line 108: / Line 112: @@
 ===== The brain =====
+<note tip>Note: the flight controller part below was written in late 2011, now in 2013 a all-in-one flight controller is a better option. The software has also been updated several times and using a several year old release isn't suggested.</note>
 ==== Assembly ====
@@ Line 147: / Line 153: @@
   - extract the "MultiWii_1_8_patch2" directory to the installed Arduino Sketches directory
   - after starting the Arduino SDK, MultiWii should be visible in the load sketches menu
-  - open the config.h and configure it based on your needs
+  - open the config.h and configure it based on your needs (changes compared to 1.8p2 defaults for FreeIMU v0.3.5_BMP and my setup)
-    * //this step will be written in more details//
+    * #define MINTHROTTLE 1180
+    * %%//#define INTERNAL_I2C_PULLUPS%%
+    * %%//#define FAILSAFE%%
+    * #define FREEIMUv035_BMP
+    * #define ITG3200_LPF_98HZ
+    * #define SERIAL_SUM_PPM ... %%// Futaba%%
+    * %%//#define VBAT%%
   - run Verify to check for errors
   - select the correct Arduino board: Tools -> Board -> Arduino Pro Mini (5V, 16 MHz) w/ ATmega 328
@@ Line 253: / Line 265: @@
 Now is a good time to do a test fit. Connect the arms to the baseplate with two M3 screws (first and third mounting hole) for each arm. Use normals M3 nuts instead of locknuts in order to ease the eventual disassembly. Attach the MWC shield with M3 nylon screws using few layers of nylon nuts to rise the shield slightly from the baseplate. Connect the cover plate with polyamid stands or something similar. Before attaching the motors, check that the frame doesn't flex in any direction. Once the motors are attached, there still shouldn't be any noticable flexibility even if the frame is handled from the tip of the arm instead of the base. Obviously, propellers shouldn't be able to make contact with each other if the given measurements were used.
+==== Power distribution ====
+The baseplates sold by [[http://flyduino.com/|Flyduino]] aren't identical. One in the set contains connections that can be used for power distribution but is also slightly heavier while the other is a plane board. Both contain the "www.flyduino.com" and "warthox" texts. I opted to use the power distribution possibility since that makes the build cleaner and simpler (=less wires). It's possible to use the power distribution enabled plate as either lower or upper plate in the frame. However, I figured that having the power distribution as far as possible from the IMU would be the best option and that's why the power distribution enable plate ended up being the lower one. The connection side if pointing up while the upper plate has the text side pointing down.
+Disassemble the frame and take the power distribution plate in view. Notice the layout of the connection pads. From the motor arm point of view, the positive and negative pads aren't always on the same sides. As a result, in order to connect the ESCs correctly, 2 ESCs will have the wires crossing each other while 2 ESCs will have wires going straight to the pads. Shortening the wire may not be necessary. It's better to have the wires doing an S shaped figure instead of going straight to the pads without flexibility. Solder the ESCs in place and also add power wires for the battery starting from the bigger pads in the center of the plate. Orientate the power wires going for the battery towards the back and use two zip ties crossing each other to connect the power wires to the outer rim of the baseplate. That way, pulling the wires will pull the frame instead of the solders.
+Using one motor arm with the motor attached as a template, figure out how much the three ESC wires going to the motor need to be cut shorter. With the Hobbywing 10A ESCs, I had to shorten the ESC wires by 7 cm each. I did a test about using the bullet connectors that came with the motors but found that those connectors are some loose and somewhat overkill considering the size of the wires. I ended up using much smaller [[http://www.hobbyking.com/hobbyking/store/%5F%5F15424%5F%5F6pin%5FMicro%5FPlug%5F10pairs%5Fbag%5F.html|micro plugs]] from HobbyKing instead. Shrink tube was used over the connector pair once the correct orientation was found. Notice that the Keda motors can have the motor wires in totally random order. That's why it can't be assumed that using the original order will result in the motor spinning in the same direction every time. Make sure to double check that the direction is correct since half of the motors need to be spinning clockwise (front left and back right) and the other half counter clockwise (front right and back left).
+The ESCs should now be connected to the baseplate and connections to motors ready.  Now is a good time to calibrate and configure the ESCs and check motor spin directions before connecting anything to the Arduino. Power up the ESCs using the baseplate with the ESCs connected to a motor without a propeller. One ESC at time should be connected to the receiver channel 3 or a programming card if such is available. Note that the travel range can't be set with a programming card so the transmitter and receiver need to be connected for each ESC at least once. The transmitter should be already calibrated to output the correct value range as explained in the transmitter setup section. Depending on ESC & motor combination, high timing may be needed. With the Hobbywing ESCs and Keda motors I didn't notice any difference between middle and high timings with a bench test.
+^ ESC setup ^^
+| Brake |  OFF  |
+| Battery Type |  Li-xx  |
+| Cut Off Type |  Soft-Cut  |
+| Cut Off Voltage |  Low  |
+| Start Mode |  Normal  |
+| Timing Mode |  Middle  |
+| Music |  OFF  |
+| Governor Mode |  OFF  |
+While playing with the motors (without propellers!), take note if any motor feels or sounds like it would have a different vibration profile that the others. In a optimal situation, all motors would be identical but that's not how things end up being in real life. I found that the propeller mounts aren't all 100% balanced but luckily it's possible to mount the propeller mount in four different ways. If the motor seems to be vibrating much, rotate the propeller mount mounting and try again. Repeat until the orientation causing the least amount of vibration is found and use it.
+Balancing any rotating parts is one key element in getting a well flying quadcopter. Remember to also balance the propellers. So far I haven't found propellers that would be directly in perfect balance.
 ==== Let there be light! ====

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