10
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what is the algorithm to get position (Linear displacement and linear velocity ) using IMU (Like MPU6050)?
I thought for sure that there would have been a duplicate question somewhere on the site that answers this question, but I can't find one, so here's a quick description of the method.
Put your IMU ...
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6
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Accepted
How to measure pull force on a (kite) rope?
The component you highlighted is called a tensile load cell. You could buy one from a supplier, but it probably would be cheaper to buy a cheap digital hanging scale and taking the sensor out of it - ...
- 521
5
votes
Accepted
Will this pseudocode work as a basis for a flight controller?
The signals to the ESC's using PWM should be sent after the PID algo is done processing the errors. The output calculated from the PID is the PWM value to be sent to the ESC's to actuate the motors in ...
- 732
4
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Holonomic and Non-holonomic UAV's: Gliders vs Quadcopters
The glider definitely is a nonholomonic system, but not (only) because it has no propulsion.
As Wikipedia defines it:
A nonholonomic system in physics and mathematics is a system whose state depends ...
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Fixed Wing UAV: Do inherently unstable systems desire to be stable for all cases when a closed loop control is implemented on them?
Not all fixed wing aircraft are inherently instable. That feature greatly depends on the center pressure and gravity center designed position. Passenger aircrafts are quite stable, and fight planes ...
- 470
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Why does the Pixhawk have 2 IMUs
This was on rcgroups:
Reply by Rob_Lefebvre on December 31, 2014 at 7:02am
Here is a brief history:
The APM class boards used the MPU6000 gyro/accel chip.
The Pixhawk was originally ...
- 41
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Is MoveIt! suitable for fixed-wing aircraft path planning and obstacle avoidance?
Not really MoveIt! is designed for robotic arms, and is being heavily adapted for the applications you see here, fixed wing aircraft typically use very diffrent types of motion planning becouse of the ...
- 1,909
3
votes
Generate a coverage path given a polygon region
This thing is generally called coverage path planning.
If you are particularly interested in Boustrophedon Cell Decomposition, you may have a look at the paper introducing it: Choset and Pignon (1998)...
- 1,829
3
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Displacement with accelerometer
This will depend on what you mean by "displacement" and for how long you want to do this. Can you supply more details on what your trying to accomplish and why?
As Bending Unit 22 mentioned, you ...
- 106
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Are there any aerodynamics modeling/simulation software that is capable to consume a SolidWorks model and to interface with MATLAB/Simulink?
Matlab has a package called Simscape that you can use for modeling physical systems in general. I would just caution you up front that Simscape is almost more like a plugin manager in that it enables ...
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2
votes
Accepted
Fixed Wing UAV: Do inherently unstable systems desire to be stable for all cases when a closed loop control is implemented on them?
I'm going to ignore your section on aircraft and attempt to answer the (vague) question,
Do inherently unstable systems desire to be stable for all cases when a closed loop control is implemented ...
- 15.9k
2
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Generation of a trajectory (position,velocity,acceleration) from velocity
With the method you describe you are bound to have non zero velocity or non acceleration (based on if you consider a + pi/2 offset or not).
Despite @combo answer I would suggest you a second order ...
- 1,402
2
votes
Are all drone propellers compatible with all brushless motors?
Not at all. It is about efficiency, agility, and maneuverability of your drone.
Just like wheels on a car, the size of the propeller needs to be matched to the rest of the power system. For ...
- 96
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How is the IMU used in the PixHawk?
Take a read here and here.
The Flight Management Unit (FMU) board and the IO board combined make a Pixhawk autopilot.
The FMU is contains the control logic and the sensors while the IO takes care of ...
- 550
2
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Battery weight in quadcopter
Every quadcopter design is relatively unique and there's not one answer for any given system. Many factors can change these numbers, for example the type of blade, the material the angle of attack, ...
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1
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what is the algorithm to get position (Linear displacement and linear velocity ) using IMU (Like MPU6050)?
I can't comment in this forum yet, so I have to post an answer, but I am looking at the same problem. The MPU9250 DMP output includes a quaternion and a fused quaternion. I can't find an exact ...
- 11
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How to implement a novel control algorithm for a drone
Assuming you know how to model a regular quadrotor as $\dot{x} = Ax + Bu$, the only difference with the addition of the extra propeller will be in your control matrix and control vector (one more ...
- 71
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vote
How many independent control inputs does a hexarotor have?
When assuming that the axles of all the rotors are oriented parallel to each other then the thrust will also only be along the same direction as these axles, so this only adds one degree of freedom. ...
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How to convert raw Pitot tube readings to air speed in m/s?
In a classic pitot tube setup, we make use of a liquid (density $\rho$)in a U tube. One end of the U tube is connected to the dynamic pressure source (front of the pitot) and the other end is ...
- 41
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How to measure pull force on a (kite) rope?
That is a load cell, comprised of four strain gages in a Wheatstone bridge, probably mounted in sheer mode to cancel out bending forces.
1
vote
CC3D PWM control signal characteristic (to be simulated by Raspberry PI)
Ok I actually was able to make it work.
First of all in the beginning of the testing I used my own program which generated PWM signals. I wanted to make them 50Hz with 1.5ms of duty cycle being ...
- 31
1
vote
Accepted
Estimating the displacement of a drone in three dimensions
If the robot's orientation is fixed, then determining its linear displacement is sufficient to determine its location in the world. This is because one unit of "forward" on the robot is equivalent to ...
- 15.9k
1
vote
Possible stabilize Crazyflie 2.0 drone autonomous flight without additional sensors?
You will not be able to achieve stable horizontal flight without external sensors. The reason is that the Crazyflie 2.0 quadcopter does not have sensors to know where it is in the room, it only has ...
1
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Possible stabilize Crazyflie 2.0 drone autonomous flight without additional sensors?
tl;dr - You can't control the aircraft's side-to-side motion because you are only modifying "thrust", which controls the up-and-down motion. If you want to control roll and pitch (side-to-side motion),...
- 15.9k
1
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Utilizing the inertial sensors in an AR Drone
That's because your fixed frame is set to /odom (Essentially, you're setting your global frame to your local frame, so relative to the vehicle itself, the vehicle never moves!). The solution would be ...
- 1,096
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Compatibilty of my setup?
The website that you have used seems to be down, however looking at the specs announced on banggood, it looks compatible.
You would need some 8*4 props and a 3S battery, I'd advise getting a 3000mAh ...
- 53
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vote
Vision-based Position Estimation for a quadrotor
Because a camera is a range-only sensor, you cannot directly estimate the relative position of the object.
Additionally, because you have only one object, there are infinite solutions that are equally ...
- 892
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Vision-based Position Estimation for a quadrotor
It's odd that you're suggesting computing the position of a landmark. Literally, a mark on the land -- a position that you should already know and will use to localize your vehicle. You can give it ...
- 11k
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How to estimate the position of multiple static ground targets captured from a down facing camera?
I see that you updated your question some, but maybe it's your scenario that's not clear. If your targets are all of about the same size, and all on a flat, level plane, then I can see that you could ...
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1
vote
Accepted
CC3D - Replacing RC emitter with an RPi
I could finally control the CC3D from the RPi.
The problem was a bad configuration from a RC input.
I also upgrade the CC3D firmware from the new Groung Control System software developed by ...
- 358
Only top scored, non community-wiki answers of a minimum length are eligible