Inhaltsverzeichnis

KK Xcopter 4.7 issue

There is a problem with the motor 4 signal on the Xcopter 4.7 firmware from kapteinKuk. To solve it I will post here some PWM readings I did with my logic analyser.

How the experiment was done

I used my Futaba T10 with Frsky module using a V8 7-channel receiver. The value of the throttle channel was set in the servo monitor of the TX, so I was able to set the value every time the same. I recorded the output of M1-M4 and the throttle input signals with a logic analyser, 1 million samples at 50kHz. The PWM signal had a accuracy of +-2%. I used two boards to do the first experiment:

Tested firmwares are:

Results

KK Quadrocopter 4.7

PWM refresh of M1-M4: 299.4 Hz

<columns 100% 33% →

board1
TX KK board
Stick posThr valueThr valueM1M2M3M4
12% -92
25% -62 1.26 1.12 1.28 1.10 1.10
50% 0 1.52 1.38 1.52 1.34 1.20
75% 63 1.78 1.62 1.78 1.60 1.44
100% 125 2.04 1.88 2.00 1.86 1.68

<newcolumn>

board2
TX KK board
Stick posThr valueThr valueM1M2M3M4
12% -92 1.16 1.08 1.18 1.08 1.08
25% -62 1.28 1.14 1.32 1.10 1.08
50% 0 1.54 1.38 1.58 1.38 1.18
75% 63 1.78 1.64 1.82 1.60 1.42
100% 125

<newcolumn>

board3
TX KK board
Stick posThr valueThr valueM1M2M3M4
12% -92 1.14 1.02 1.02 1.02 1.02
25% -62 1.26 1.16 1.18 1.12 1.12
50% 0 1.52 1.36 1.48 1.36 1.24
75% 63 1.78 1.64 1.74 1.62 1.48
100% 125

</columns>

KK XCopter 4.7

PWM refresh of M1-M4: n Hz

<columns 100% 33% →

board1
TX KK board
Stick posThr valueThr valueM1M2M3M4
12% -92 1.16 1.02 1.02 1.02 1.02
25% -62 1.26 1.22 1.18 1.18 1.10
50% 0 1.50 1.48 1.44 1.42 1.10
75% 63 1.78 1.74 1.70 1.68 1.38

<newcolumn>

board2
TX KK board
Stick posThr valueThr valueM1M2M3M4
12% -92 1.14 1.12 1.10 1.08 1.08
25% -62 1.28 1.26 1.24 1.20 1.08
50% 0 1.54 1.50 1.50 1.48 1.10
75% 63 1.78 1.74 1.74 1.72 1.30

<newcolumn>

board3
TX KK board
Stick posThr valueThr valueM1M2M3M4
12% -92 1.14 1.02 1.02 1.02 1.02
25% -62 1.26 1.12 1.26 1.12 1.12
50% 0 1.54 1.34 1.56 1.30 1.32
75% 63 1.80 1.62 1.76 1.58 1.52

</columns>

KKAJ XCopter 1.1.2

PWM refresh of M1-M4: 256 Hz

board1
TX KK board
Stick posThr valueThr valueM1M2M3M4
12% -92 1.16 1.02 1.02 1.02 1.02
25% -62 1.28 1.22 1.20 1.20 1.10
50% 0 1.54 1.42 1.40 1.40 1.30
75% 63 1.78 1.64 1.64 1.64 1.54