Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [compass]

A compass is a sensor which detects its orientation with respect to the earth's magnetic field, and displays it or outputs as an electronic signal.

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What are the differences between a gyroscope, accelerometer and magnetometer?

What is the difference between a 3-axis gyroscope, 3-axis accelerometer and 3-axis magnetometer? How do these sensors work? Why are all 3 used in some devices like smartphones, tablets, quadcopters etc.?
Kicsi Mano
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Why do compass chips in cellphones require frequent calibration?

Most cell phones offer digital compass functionality which uses a 3-axis magnetometer chip for data. Phones (some more than others?) frequently require the user to "recalibrate", which involves rotating the phone in a "swirly" or other pattern to…
uhoh
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Digital Compass identifying direction of travel for use with trains

I work in a control center for a train company in the UK. Our trains work in either direction but only one end has first class carriages. Because trains on our network reverse quite a lot it is difficult for us to track and advertise where first…
Daniel Autiero
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Establishing ground truth in a particle filter experiment using compass and gyro

I'm working on coupling gyro and electronic compass for better accuracy of device orientation (using particle filters). I have one basic question, though: how do I establish ground truth in this case? I cannot use the compass readings alone, since…
Imelza
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How is the degaussing feature in the HMC5883L 3-Axis Digital Compass chip correctly used?

edit/tl;dr: The set/reset strap driver is an H-bridge circuit to deliver 10 mA of DC current to a strap which temporarily produces about a 1.1 gauss magnetic field offset. A change in the measurement before and during this field offset can be used…
uhoh
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Determine the angle and speed of a rotating platform

I have a 1 axis (x) spinning platform, that is spinning pretty fast ~300 RPM. I want to be able to detect with a good degree of precision how many degrees it has travailed from its starting position and the speed it is currently trailing at. For…
Steven Smethurst
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Digital Compass: Can it be calibrated/shielded to prevent normal operation in the presence of ferromagnetic materials

I am currently working on a hobby project, for which I would need a reliable compass that should work in as wide a range of environments as possible (i.e.: In a field, in a car, on a train, possibly even on an airplane) I chose the LSM303DLMTR tilt…
Mark Anderson
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Would a digital compass work reliably when installed in a car?

I'm working on a project that needs dead reckoning sensors to combine to GPS readings, and is to be installed under the dashboard of a car. Currently I have an accelerometer and a gyroscope for that. I'm thinking of getting rid of the gyroscope,…
fceconel
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Calculating weights in a particle filter experiment using multiple state variables

I am trying to implement a particle filter for coupling gyro and electronic compass for better measuring device orientation. [related question] I understand my state vector would contain the absolute angle and turn-rate and my observation vector…
Imelza
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SensorTag- Magnetometer to compass

I have a sensor tag from Texas and have been able to communicate with it over BLE and get magnetometer readings using a node.js library. However I am tough time going from the x,y,z mag. axis readings to being able to say NORTH, SOUTH, EAST, WEST.…
Dhruv Kapur
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Can I use tinkerkit hall sensor as compass

I'm using Tinkerkit shield in combination with an Arduino standard board. I need a simple compass sensor in order to determine the direction (I don't need a great precision), unluckily similar sensor that works "out of the box" with Tinkerkit does…
Griffosx
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Measure RPM with a discrete component?

I have a problem that I need to measure an RPM of a rotating axle with a single element (circuit) attached to it - i.e. I can't use a hall effect sensor, because I can't use a separate magnet - I can only use what's mounter on the axle. The axle…
MeLight
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Gyroscope and compass. When its better to use one instead of another?

Why people prefer gyroscope instead of compass? Does gyroscope replace compass? I would like to see the pros and cons of each.
Loclip
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Cheap indoor compass

I am trying to build a simple RC rover (car with only two wheels). On certain commands, I want it to rotate a specific number of degrees into a direction or another (don't want military precision). In other words, to change it's orientation by…
caffeine
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GPS in combination with servo on Arduino

Me and my friends are building a boat which needs to steer towards certain coordinates. We have a GPS and a compass on board. We have written code which calculates the direction that the boat has to steer. When we plug in our GPS together with the…
Just van Til
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