Questions tagged [quadcopter]
A quadcopter, also known as a quadrotor, is a multirotor helicopter that is lifted and propelled by four rotors.
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Trajectory optimal for quadcopter
I have defined a quadcopter that I control with a PID controller. The dynamics that define it are such.
$T=mg+m\ddot{z}$
$\theta=\frac{\ddot{x}}{-9.82}$
$\phi=\frac{\ddot{y}}{9.82}$
As you can see I ...
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2answers
100 views
How do I find the transfer function for my quadcopter altitude system?
This is not so much of a how but if I am right so far. I am looking at the z-axis now only. The linearized equation of motion for the thrust in the z-direction is:
$$
T=m\cdot \ddot{z}+mg,
$$
where $m$...
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55 views
Air Resistance Drag Force Calculation For Quadcopter
Hello there. Hope you are all doing well.
I have created a dynamic quadcopter model on Simulink and designed a controller for it. So far, everything is going well. However, since I am going to be ...
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1answer
56 views
Mapping Joystick Inputs to Quadcopter
hope you are all doing well.
We are doing a project where a quadcopter is controlled by an ordinary joystick. We have constructed the Control Algorithm and the joystick to move the quadcopter in ...
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1answer
17 views
Why does the quadcopter become unstable after turning?
I'm trying to write a simple test MAVROS node where my quadrotor is expected to go in a straight line and then have 180-degree turn and come back and land on where ...
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1answer
111 views
Can someone explain this yaw angle calculation equation?
Nowdays, I am trying to understand PX4 Autopilot(Drone Flight Control Open Source) attitude control code. But I can’t understand formula below which is in attitude control code description.
Can anyone ...
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1answer
132 views
Drone Development using ROS Noetic on Ubuntu 20.04
I installed ROS Noetic on Ubuntu Mate 20.04 in my Raspberry Pi but couldn't find any specific tutorial to follow along for Noetic. Most are available for Melodic, which doesn't work with the latest ...
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1answer
35 views
What devices can I use as a flight controller in a Quadcopter project? [closed]
I know that the flight controller is the heart of the quadcopter and a device which has to be considered greatly when building a quadcopter project. In regards to this quadcopter project that I'm ...
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1answer
50 views
Drone lost traj recovery
So I am using slam algorithm to localize the drone which is gps denied . The input to the slam algo is imu data and a video .
Now after the first run of the slam algorithm it creates the trajectory ...
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22 views
Quadrotor Smooth Trajectory optimization
I'm currently following a course on coursera on quadrotors, and i'm currently focusing on the trajectory planning mechanism.
In the course, it's said that one of the criterias when planning a ...
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1answer
64 views
Inertial frame's angular velocity expression
I'm following a robotics course on coursera which talks about aerial robotics and more specifically quadrotors.
I'm trying to understand the logic behind the relationship between the angular velocity ...
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1answer
104 views
Inertial frame VS Body-fixed frame momentum correction factor
I've recently enrolled in a Coursera aerial robotics course and i'm trying to understand how the rate of change of the angular momentum is computed from the inertia frame to the body-fixed frame.
...
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2answers
97 views
Quadrotor dynamics: How is torque created
I'm a software engineer and I've recently engaged into Robotics field. I've started by a course on Coursera which talks about Aerial robotics and thus quad-rotors. I'm trying to understand how quad-...
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1answer
42 views
When is the Quadcopter out of the control?
Assuming ideal environment/hardware flying conditions, is it possible that the autopilot loses the control of the quadcopter?
What is the maximum tilt in roll and pitch that is allowed for the ...
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1answer
50 views
Quadcopter descends when rolled or pitched
I'm currently working on a quadcopter using f450 frame and YMF32 code. I was able to successfully build the quadcopter and It flies without having any vibrations or wobbles. Also, I tuned the PID ...
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2answers
75 views
Generate a Trajectory from GPS coordinates
How would I generate a trajectory (e.g. minimum snap/jerk/acceleration) for a quad rotor between GPS coordinates? In all the examples that I have seen, they assume that the x,y positions are in meters ...
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Is Image Based Visual Servoing a non-linear controller?
Is Image Based Visual Servoing a non-linear controller? I think it is as the Image Jacobian has square terms of u & v (image-plane coords).
Where $p_u, p_v$ are the width & height of each ...
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Calculating lift capability and current draw of quadcopter motors
I have seen a lot of posts citing this answer which gives the rough estimate that a quadcopter needs approximately 150 watts of power per kg in order to hover. I am trying to do some theoretical ...
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1answer
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How to make a quadcopter hover when tilted forward or backward?
is making a quadcopter hover forwards or backwards possible ? The only two ways I can think of making this happen is by using motors to move the rotors in such a way that they are always vertical and ...
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3answers
189 views
Quadcopter PID Controller for distance
I am trying to use a PID controller to stop a quadcopter at a specific location while travelling horizontally, however currently it overshoots/undershoots depending on the max velocity. I have tried ...
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1answer
73 views
Imaginary part in result of inverse laplace transform
I am working with a system(closed-loop feedback control) that has a transfer function like this
F = 20*(s+5)/(s^4+13.5s^3+41s^2+80*s+100)
this one is in the s-domain but for the response analysis, I ...
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1answer
86 views
What flight firmware stack is most common in aerial robotics research environments?
I'm considering Aero-Astro grad school and am looking into acquiring a drone hardware platform to implement GNC/ PNT/ autonomy papers like those I might see from, e.g., the Navigation and Autonomous ...
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33 views
Barometer altitude calculation
I want to calculate altitude using a barometer which is mounted in the proximity of a number of components which get quite hot and raise the localised temperature. The barometric pressure equation is ...
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2answers
148 views
Detection of linear acceleration vs rotational velocity/acceleration
I am wondering, how do you differentiate between linear acceleration and rotational velocity and acceleration for IMU? A rotational velocity or acceleration will still appear to the accelerometer as a ...
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1answer
76 views
For a quadcopter do i need to place the gyroscope sensor at the center of mass?
I am trying to build a quadcopter and think it is essential to have its center of mass in the middle. Therefore, I am planning on putting the battery in the center. However, this will cause me to ...
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1answer
34 views
BLDC Stuttering when attached to Arduino Nano
I am working on building a quadcopter with an Arduino nano. I am currently only working with 2 motors. However, I am experiencing an odd issue. When I try to run my motors, one of them runs fine, ...
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68 views
How to calculate the pitch of the quadcopter rotor blade and their efficiency?
I have gone to some of the blade designs and profiles of the blade which suits my requirement. But, once after entering the Theoretical calculation, I was stuck in the determination or the ...
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1answer
37 views
Setting up rewards to account for UAV crashes (Reinforcement Learning)
I am working on a project to implement a collision avoidance algorithm on a real UAV. I'm interested in understanding the process to set up a negative reward to account for scenarios wherein there is ...
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1answer
84 views
Measurements of IMU (accelerometer and gyroscope) are drifted or with too much error
I placed my drone on a table (i.e, at rest) and save (using a ROS topic) the IMU readings:
As you can see, there's a lot of drift or error. I would expect the $x$ and $y$ acceleration to be 0 (I know ...
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1answer
305 views
What is a low level controller for a quadrotor?
I am studying control systems, and I was reading a paper about quadrotors. In the paper it is said that in the platform of the robot it has to be present a low level controller.
But what is a low ...
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1answer
27 views
Numeric integration problem in a quadrotor vertical descend code
I'm trying to implement a drone in vertical descend. As for maximum simplification, I maintain all its angles to 0, and just try to get to the my desired descend. However, when I debug, I see that my ...
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1answer
108 views
Tuning a cascaded attitude and attitude rate PID controller
Assume that I have an object in 3D, and I want to have a controller that stabilizes its orientation (also referred to as "attitude").
To be sure we are clear:
attitude is measured in "degrees" or "...
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41 views
Proper Joystick Inputs for UAV Quadrotor Control
I am working on the adaptive control of quadrotor UAV in MATLAB/Simulink environment. I prepared some trajectories for the UAV to follow in $x$, $y$ and $z$ directions. I would like to implement these ...
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31 views
What happens when I send the land command to my quadcopter?
My first question is: imagine I have a self-made quadcopter and I want it to land. How can I achieve that? Do I have to stop the 4 motors at the same time?
Second question: I use an AR.Drone 2.0. ...
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1answer
473 views
what kind of processing is required on raw IMU data before it is fed into a filter?
Im working on quadcopter. At this stage im coding a reference system for quadcopter using 10DOF board.At this stage im at the point of only getting raw data values from accelerometer, gyroscope, & ...
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1answer
166 views
Solving for rotation matrix: Aligning vector a with vector b and then rotating around vector b
Currently working on a quadcopter simulation. I have a desired thrust vector,
t =sin(30)cos(45)a1+sin(30)sin(45)a2+cos(30)a3
and desired yaw angle,
...
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53 views
Roll, pitch and yaw in a quadcopter
The axis definition affect the roll, pitch and yaw definition in a quadcopter?
Image I have the axis defined this way:
then to roll I have to put a higher velocity in (1) than in (3) (turn around ...
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1answer
48 views
Drone or UAV Platform for deployment of Deep Learning / Reinforcement Learning
Good day,
It has been a while since I last posted. I would just like to ask if anyone part of a lab or company doing research on aerial robotics has any suggestions of a good platform for deploying ...
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1answer
92 views
How to simulate a quadcopter using robotics simulator?
I am building my own autonomous quadcopter. I wish to simulate it using V-REP/Gazebo in order to tune the flight controller. I see that there are inbuilt models but they have properties(physical ...
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1answer
55 views
BLDC Outrunner Direction Change?
I'm designing a Quadcopter for my project. I've seen a lot of guides that the motor rotational direction should be opposite to each other. My doubt is whether the motor have a variety of CW rotation ...
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2answers
296 views
How to calculate the maximum charge of the battery?
How to calculate the maximum charge of the battery that it can give from a fully charged state to a fully discharged one. I have been trying to solve this problem for 2 months. The drone itself is not....
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1answer
56 views
Drone Horizontal Speed Measurement
Assuming no GPS is available, what can be used to measure the horizontal speed of a hypothetical drone? Sensor mass and size don't need to be taken into account. Could small Doppler radars , maybe ...
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How to prevent loss of mavros msg packets?
I am working with Pixhawk 2.1 cube, using telemetry module and mavros to establish communication between vehicle and companion computer. I am using rostopic echo to save /mavros/local_position/pose ...
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1answer
23 views
Can I use 3 blades instead of 2 blades with the same pitch and dia to increase the thrust of my motor?
Can I use 3 blades instead of 2 blades with the same pitch and dia to increase the thrust of my motor? Will it burn my motor? or it will damage my ESC? Some motors are having high torque but low rpm, ...
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1answer
27 views
How should i select motor and blades for my Hexacopter?
I'm designing a fluid sprayer Drone (HEXACOPTER) for Agriculture as my college final year project. The capacity of the fluid spraying unit including fluid & Sprayer around 2kg. I don't know how to ...
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Flysky I6 transmitter not responsive on betaflightl
I am building a fpv quadcopter and I encountered the following problem:
I soldered all points correctly into their allocated pads and ensured there were no shorts. I use a racerstarf4s flight ...
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1answer
49 views
Can I preload a mission into my drone (navio2) so it can execute it without being connected to a ground station by telemetry during flight
The question really speaks for itself. I don't have any way to connect with my navio2, running ardupilot, during flight (except a radio controller if things go wrong). Could I still make my drone ...
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1answer
42 views
DJI on-board SDK vs. mini computer
I am planning to integrate a LIDAR sensor on my DJI Matrice 100 and I will use the data generated to control the height of my UAV. I was wondering if I would need to attach a separate processing unit ...
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1answer
27 views
Quadcopter for modest payloads w/SDK?
I'm interested in attaching custom camera(s) to a quadcopter that can carry a modest (<0.25 kg) payload.
I prefer to write code to fly the quadcopter (e.g. traverse a region and image) rather than ...
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212 views
Why am I unable to tune the PID parameters on my quadcopter?
I am building a nano quadcopter in X-Configuration with coreless DC motors, 65mm 2 blade propellers and a 1S Lipo battery (860mAh, 25C). The weight of the assembly is around 70g in total.
I am ...