Questions tagged [sensors]

A sensor (also called detector) is a converter that measures a physical quantity and converts it into a signal which can be read by an observer or by an (today mostly electronic) instrument.

43 questions with no upvoted or accepted answers
Filter by
Sorted by
Tagged with
510 views

How does one implement a third order complementary filter for estimating altitude using data from an accelerometer and a barometer?

I am working with the CJMCU build of cleanflight on a small drone. As of now, the algorithm for altitude hold uses a first order complementary filter to combine data from the barometer and the ...
194 views

Nonlinear Sensor Fusion with Space-Time Finite Element and Static Condensation?

I have recently implemented an algorithm for the nonlinear fusion of GNSS, barometer, magnetometer, accelerometer and gyroscope data. The algorithm is based on a space-time finite element where the ...
• 31
88 views

How to fuse IMU with encoders in EKF

Background I have a car-like mobile robot (4 wheels, where the forward ones are steering wheels) and I want to estimate its pose and velocity assuming 2D planar motion. I'm trying to solve this ...
430 views

How to estimate yaw angle from magnetometer and gyroscope?

I'm using the MPU9250, it measures acceleration, magnetometer, gyro, etc. Complementary filter tutorial for this is here, however this tutorial does not have a magnetometer and I do, thus I thought I ...
200 views

How to handle sensor data for a sensor-fusion algorithm

I am implementing the explicit complementary filter(see below) with a 9DOF MEMS sensors (accelerometer, magnetometer and gyroscope) for attitude estimation. Currently, the gyro and accel update rates ...
• 21
161 views

Magnetometer Calibration

I'm looking at using a magnetometer in a project and I'm struggling to understand the proper procedure for calibration of the sensor. I understand that magnetometers need to be calibrated to ...
• 21
1 vote
42 views

Using an optical mouse sensor for odometry?

I'm trying to use a mouse sensor for odometry on my robot. Most datasheets I have found use SPI or SDIO interfaces for communicating but my microcontroller would require an I2C interface. Would it be ...
1 vote
77 views

Gazebo Garden plugin and nested models?

I have a problem that I'm not able to solve with Gazebo Garden. I wrote a System plugin that handles a stereo camera, I need a plugin to interface the simulator with our SDK. Differently from Gazebo ...
• 111
1 vote
63 views

how to calculate the accuracy of data received from RTK-GPS?

I have received data from an RTK-GPS, in an environment free from buildings and other GPS obstructions. the covariance of these data is 0.01. now I do not know this is good or not? How can I find out ...
1 vote
15 views

How to set "fast mode" in low cost DRO

I have this cheap DRO from Amazon/China https://www.amazon.com/gp/product/B00E7XFF5Q/ref=ppx_yo_dt_b_asin_title_o07_s00?ie=UTF8&psc=1 I'm able to read the values out of it using a small FPGA. The ...
• 141
1 vote
57 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 ...
• 69
1 vote
61 views

Tracking object in realtime using depth image stream from a RGBD camera

I have an Intel RealSense camera which can stream RGB and depth image. Using those information I want to track an object moving on a table top. More specifically, I want to know position $(x,y)$ and ...
• 111
1 vote
268 views

Detecting and counting the number of junctions

So I am making a robot which is to follow a line. The field has both +(junctions) as well(by the intersection of two lights). I am yet to figure out what exactly is the best way to track the number of ...
• 111
1 vote
148 views

Kalman filter localisation equations

I am doing mobile robot localisation as a project. Now I stuck in obtaining the equations of EKF localisation. My robot moves straight for 10 seconds parallel to x-axis and robot equipped with 2 ...
1 vote
89 views

How can there be a difference in quaternion values of two points taken from sensors where the orientation is exactly same?

I have two situations- A) One, the body with sensor embedded in it kept at rest. B) Second, the body is at rest for 10 secs, then undergoes some movement randomly and comes back to the exact ...
• 11
1 vote
148 views

control a robot with pymorse on MORSE simulator question

I am new to Morse and robotics. This code control the robot by giving the linear and angular velocity. This is the scene description ...
• 19
1 vote
67 views

Can active sensor data be fed into an Autodesk Inventor Simulation?

I'd like to drive the position of various components within a virtual assembly based on sensor data being collected in real time from an external device. Does Inventor support such a setup? The goal ...
• 11
1 vote
83 views

computer aided RC airplane combat

http://www.youtube.com/watch?v=4Vh_R1NlmX0 is from 2011 SWARM and shows RC aircraft or combat wings trying to hit each other in the air. Scoring a hit is pretty rare, and I'd like to increase a ...
• 111
1 vote
660 views

I need to track a point in space. The point is less than 2 m away, it has to be passive, no batteries, and no charging. I don't always have a line of sight. I need to pinpoint it to about a ...
16 views

Do MEMS or optical gyroscope record Earth's rotational and revolutional angular velocities?

I am using a 3 axis gyroscope (Android device) to record angular velocities using a sensor data logger application. When the device is placed stationary, the gyroscope recorded the following values: ...
13 views

Object racking on conveyor belt using low cost Lidar or similar non-camera options

The requirement is that movement of products right from the start to end of the conveyor belt (of length around 2.5 m) need to be tracked. The same can be easily done using any IP Camera and OpenCV ...
• 1
46 views

Rotate sensor frame to body frame

I'm working with a lsm303agr from ST. Here is the frame attached to the chip Here is the body frame So I have some doubts about the rotations, before to fuse data ...
• 163
13 views

How does the lightsensor values work? Lightsensorvalue into Percentage

In Webots: I try to build a Braitenberg vehicle so that when it receives light information through the ligh sensors it drives either away or towards the light. I used an ePuck and tried to just ...
• 25
17 views

Confused in Regards to Sensor Models, Laser Scans and Ray Castings

I have started studying Robotics recently from Probabilistic Robotics by Thrun Burgard and Fox. Our objective in the sensor model is to compute $$P(Z_t|X_t)$$ But for this we need to know $z_{exp}$ (...
• 141
19 views

Are there low cost options for producing high pressure at low flow rates?

I'm looking for a low-cost way for a device to produce up to 4 bar pressure. Flow rate at that pressure almost doesn't matter; 2L per minute would be ample. All the options available seem very over-...
• 101
42 views

PID controller feasibility

I'm trying to control a hybrid inverter to manage a selfconsumption mode bypassing its native mode - meaning to distribute power coming from solar and into/from battery to home consumption and grid. ...
13 views

Nao robot IMU data rates

I'm trying to stream data from the Nao's inertial unit in its trunk. However the update rate is quite slow ~ 1Hz. Is there any way to improve it? For reference, I issued the following command using ...
• 101
57 views

Custom sensors and materials simulation in Gazebo: how to simulate specific sensors behaviors for heterogenous materials / buildings

We are currently working on a simulation for a drone that would evolve in an urban environment. It would flight in front of facades and thus must avoid collision into walls, balconies, windows, etc. ...
150 views

GPS + IMU data and kinematics equations

I have the following data Longitudinal acceleration, $a_x^{IMU}$ Lateral acceleration, $a_y^{IMU}$ Vertical acceleration, $a_z^{IMU}$ Yaw angle, $\psi$ Yaw rate, $\dot{\psi}$ Latitude, \$\rightarrow ...
• 101
72 views

How can I feel feedback with electric power steering (EPS)?

When I am rotating steering wheel and it meets an obstacle, I feel it. I have EPS. How does it work? Is it just explicit sensor and feedback? Can I sniff this feedback on CAN bus?
• 115
10 views

Real-Time, App-Based Tool Tracking and Inventory Management System

For one of my classes, I need to create a sensor system that can connect with an app that will be able to track when specific tools leave a certain area. I do not know which sensor to implement that ...
15 views

What are common method for sensor feedback in teleoperated underwater ROV to close the control loop

I would like to know what are the common method to get sensor sensor feedback in teleoperated underwater ROV to close the control loop. I mean does it use Velocity or Force and what sensor are used. ...
• 167
96 views

How to create pseudo code for Braitenberg vehicle 2b?

I am asked to make Braitenberg vehicle for small robotic exhibition. I am asked to use GL5528 light sensor. My job is to construct and program Braitenberg vehicle 2b, which uses GL5528 light sensors ...
139 views

Simulating sensor readings based on an existing Alan Variance Analysis

My goal is to model an accelerometer and a gyroscope based on real hardware. I understand deterministic errors like bias and scaling but the different types of non-deterministic errors are difficult. ...
• 41
35 views

How to loop various conditions multiple times

I have 2 arrays (s_left and s_right) a length (dis), the arrays in reality are produced from sensor values. The first situation entails looping the condition (s_left < dis) twice and at the same ...
• 113
38 views

How to obtain airspeed data

I want to measure the airspeed on a flying vehicle and get the data with a microcontroller. Note that, there will not be any control mechanism on the flying object, it will be flying mechanicaly/...
• 153
51 views

Can a RPI3B+ handle all this?

I am building a robot that needs to accomplish the following tasks: Keep track of 4 quadrotor encoders, each 979.62 CPR @ ~ 500RPM, so ~ 8163.5 counts per second Read from an RPlidar A1M8, giving out ...
• 135
60 views

Choosing a position sensor (encoder) and obtaining velocity from it

How do I know how many counts per revolution I need for an encoder for my application? I need to be able to accurately capture a 1000 Hz signal on an input side running from 1-133 rev/sec (60-8000 ...
• 31
168 views

GraphSLAM data accumulation problem

I try to implement GraphSLAM from this tutorial, The GraphSLAM Algorithm with Applications to Large-Scale Mapping of Urban Structures. I have some doubt while studying this paper. I hope people who ...
• 419
23 views

How to improve confidence an object is in a particular place

I'm dealing with a problem where sometimes an object I'm looking at using RF signals can appear to be somewhere it's not due to the bouncing of the waves. Currently what I have in place is a circular ...
196 views

Arduino Lightsensor Blocking Code

I have a GY-31 Light sensor and I am trying to make a skittle sorting machine. There is a little wheel skittles can drop into then they are turn to 90 degrees read by the light sensor then dropped out ...
• 101