Common questions about the performance of vehicle

Can any one tell me that what is the accurate unit of WP_NAV_VEL ? As it is written in mission planner is that 50-2000 cm/sec, but what i feel that it is wrong. Because i am flying at 50 to 200 cm/sec but flight log is telling something else. Please tell that what is the maximum velocity that a hexacopter and a quadrotor can attend during the flight with mission planner ?

WP_NAV_VEL is in cm/s and it is only used in auto and guided flight modes.
Most of the times the speed will be a bit slower than that.

But it is much slower compare to the vel that we are fixing for missions

Can you provide numbers , and flight logs ?

today i will go for a mission and upload the file.Recently i meet with a crash yesterday when flying for endurance test and SOC of battery for my powerplant over a particular weight. I am attaching the log file of that flight , will you please suggest that what could be the problem, which eventually lead to a crash ? Please suggest the options to reduce or mitigate it too.

i have checked in one of my previous flight log. The velocity for the mission i set was same as the velocity obtained from the GPS speed log.There was a speed fluctuation which is varying to and fro at 50 cm/sec.

i am trying to download sitl in window 10 but unable to do. Will anyone tell me to do the simulation in mission planner before flying in actual. Do i need to connect my vehicle even for simulation ?

No there is no need to connect to the vehicle. Just need to run the SITL program

will any one help me to identify the voltage regulator in pixhawk ? Any component no or a place on the board where i can find the voltage regulator.

That question needs to be in another topic.
The pixhawk voltage regulator is external, a small circuit board connected between the battery and evrything else like ESCs, and there’s a 6 wire cable that connects from it to the pixhawk. It provides a regulated 5 volts, current sense, voltage sense and Ground (0volts).
It’s commonly called the power brick.
Dont power anything else from it except what normally plugs into a pixhawk, like GPS and RC reciever.
Dont use a ESC 5volt BEC to power the pixhawk.

what is the maximum tilt angle, roll angle that a hexa can achieve using pixhawk ? What is the maximum velocity that can be achieve ?

There are defaults set up in the parameters, but you can set whatever you like depending on your frame, motors, battery and so on. That’s something that’s going to come with testing if you want to push the limits. Maybe if you’ve got something specific in mind and specifications (or purpose) of a craft then someone can share their experience and maybe even suggest parameters.
Defaults are something like 45 degrees max lean angle, you could set it to more if you’re chasing speed in a multirotor, but for outright speed you probably want a fixed wing or heli.

hi, i execute two missions in which i set the mission height as 6m. It is relatively showing the 6m but the flight log is telling some other data, which is indirectly indicating the height is 6 m during the mission. will anyone help to figure it out. here is the flight log for the missions.

along with it please tell me that is there any way to find out the power consume by each motor during mission ?

Hi, i need some clarification about the blanding of gps. suppose i am using 2 gps and in flight one of them fails and shows gps glitch, then what will happen if i am in gps blanding mode and in choose the best mode? Due to gps glitch i faced two major accident one of my hexa and one of my quad. please suggest me the solution of that also. In case flight log is require, plz tell i will attach that also, if needed.

Read about ESC Telemetry…

GPS blending requires you to have two GPS receivers from the same manufacturer and model.
If one GPS glitches, and provides information that it is unhealthy, the other GPS will take over.

So in some cases it increases the security a lot. But it is not effective against GPS jamming, or flying near buildings.

Sir, do you have nay idea about the response time of the pixhawk ? i mean to say after giving a particular command how much time it will take to respond. If any one having idea about the rise time and setting time ?

That depends on the size of the copter, the size of the propellers, the weight of the copter, the motors … etc.
The pixhawk is VERY fast, and the software is also very fast, especially if you use ChibiOS.
So you need to experiment with your particular frame, and tune the PID values (or use autotune) in order to optimize the response time.
After you have done all that, it should be very easy to determine the rise time and settling time of the copter ! Just measure the time it takes between you giving it a command and the time it takes to react. The dataflash logs provide all the information you need to do this.

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yes sir i am aware of doing the manual flight and post-processing, but as you said it is not a relative quantity so i will do a quick check by flying. Thanks for your help. Do you ave any idea about TCP and UDP connection ? How to establish this and do we need ant other components to connect so ?