FPV Shopping List

Pirx Seven - 7-inch FPV frame

Ladies and gentlemen, I give you Pirx Seven! The 7-inch FPV frame designed in-house to give me, and you obviously, a versatile platform for long-range, cinematic takes and freestyle!

The best 7-inch quadcopter frame - Pirx Seven

Cinematic 7-inch FPV drone Pirx Seven

Let's begin with the question: why did I have to design my own frame? There are plenty of good frames out there! True, there are good 7-inch FPV frames, but all of them have some problems: props in the view, very little space inside, thin arms, asymmetrical arms, no place for a huge battery, limited accessories and dozens of other minor things.

Pirx Seven overcomes some of them (creates a few others as well, but let's not shout about it) and truth to be told, it's the best 7-inch frame I own. After all, I designed it to solve problems I was having :)

>> Get it from Armattan Productions <<

Pirx Seven - 7-inch FPV drone frame

Pirx Seven - 7-inch FPV drone frame

Features:

The best 7-inch quadcopter frame - Pirx Seven - side view

Important notes

Does it fly?

Yeap! Take a look at fly videos:

More about the frame

>> Get it from Armattan Productions <<

Additional, 3D Printed, parts

Armattan Productions does not offer 3D printing service, you will have to print some extra elements:

Note that only an FPV Micro Camera adapter is required. All the rest are optional!

Or you can download all STL files from here: http://bit.ly/2SPdpxW

Reference setup

Analog FPV version

Digital FPV version

Settings & Tuning

Pirx Seven reference setup is based on INAV 2.6.1 as it provides full GPS long-range support as well as very good acro / freestyle flight performance. Below are key settings like mixer, PIDs, filtering and rates that you can copy-paste into INAV CLI instead of manually tuning the drone. Please remember, that if your setup is much different from the reference, you might have to adjust it accordingly.

Mixer

Pirx Seven is an asymmetric frame in a dead cat configuration. It will fly just fine with standard quadcopter mixer, but informing flight controller about the actual motor positions can improve flight performance.

mmix 0  1.000 -0.900  0.800 -1.000
mmix 1  1.000 -1.000 -0.800  1.000
mmix 2  1.000  0.900  0.800  1.000
mmix 3  1.000  1.000 -0.800 -1.000
        

Filters

set looptime = 500
set gyro_hardware_lpf = 256HZ
set gyro_lpf_hz = 90
set gyro_lpf_type = PT1
set gyro_stage2_lowpass_type = PT1
set dynamic_gyro_notch_enabled = ON
set dynamic_gyro_notch_q = 250
set dynamic_gyro_notch_min_hz = 80

set setpoint_kalman_enabled = ON
set setpoint_kalman_q = 200
set setpoint_kalman_w = 16

PID tuning

set mc_airmode_type = THROTTLE_THRESHOLD

set mc_p_pitch = 60
set mc_i_pitch = 45
set mc_d_pitch = 31
set mc_cd_pitch = 30
set mc_p_roll = 55
set mc_i_roll = 38
set mc_d_roll = 28
set mc_cd_roll = 30
set mc_p_yaw = 55
set mc_i_yaw = 65
set mc_cd_yaw = 30

set dterm_lpf_hz = 85
set dterm_lpf_type = PT1
set dterm_lpf2_hz = 130
set dterm_lpf2_type = PT1
set pidsum_limit_yaw = 400

set d_boost_factor =  1.400
set d_boost_max_at_acceleration =  5500.000
set d_boost_gyro_delta_lpf_hz = 50

set tpa_rate = 20
set tpa_breakpoint = 1200
set rc_yaw_expo = 70
set roll_rate = 70
set pitch_rate = 70
set yaw_rate = 60
        

Other

set min_check = 1050
set max_angle_inclination_rll = 500
set max_angle_inclination_pit = 500
set throttle_idle =  12.000
        

>> Get it from Armattan Productions <<

See also

Pirx 5 Freestyle

Pirx 5 Freestyle

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