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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Do factory calibrated electronic compasses need to be re-calibrated in the field?
I have been working on an electronic compass. It has become apparent the best way to calibrate the magnetometer is once out in the open with out any large metal object nearby.
Curiously, what I have ...
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Type of sensor used in rear view mirror compass
I've been messing around with hall effect style compass sensors, which need calibrated at their location to work properly. I noticed the rear view mirror in my car has some kind of compass indicator, ...
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Tilt Compass calibration using matrix multiplication: How to derive the soft iron 3 by 3 correction / calibration matrix values?
Magnetometers are useful but normally suffer from offset and magnitude errors. The offset (or hard iron) errors are corrected by adding half of the maximum minus the minimum readings for any given ...
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Difference between compass/magnetic sensor, and orientation sensor?
I want to be able to accurately measure the static 3D orientation of a drone I am building.
I understand one way to do this is to use a gyro sensor with continuous integration.
I want to combine this ...
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Why do magnetometer values change when I move PCB?
I have an MPU9250 on my PCB and I use an AHRS system with a Madgwick filter to get yaw angle. But for some reason - I can't get normal Euler angles (SO question). But I guess, I understood why. When I ...
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Compass-Needle steering PCB
I'm trying to think of the easiest/best way to steer a compass needle using a PCB. Specifically, placing a PCB of some kind under a compass (assume no shielding between the PCB and the compass) and ...
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Can you pair a compass or magnetometer with an induction circuit to create a form of metal detector?
A compass or magnetometer by themselves can only detect/measure magnetic fields, and thus would normally only be able to detect ferrous metals and (possibly) some active electrical circuits in ...
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Motor of what type should I choose?
I want to build something that behaves like a regular magnetic compass, but using this electronic compass and some motor what will rotate the arrow pointing to the north.
So I think the motor must ...
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Maximum rotation rate for digital compass
How well do digital compass ICs (e.g. HMC5843) cope with when rotating rapidly? If I were to rotate one at 1000 RPM, what kind of signal could I expect to get from it?
Would the measured bearing lag ...
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Digital Compass and Magnetic Declination Angle
I have a digital compass of HMC5883L and I want to measure orientation with it. The doubt that arise is about the magnetic declination angle. From the definition of declination angle, it is the the ...
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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 ...
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Information-Freezing values in data registers of compass module?
I am working on a compass module. This module provides the information through 6 registers. In fact, there are 3 pairs of registers.Each register pertaining to one coordinate (...
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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 ...
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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 ...
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Why compass module is affected by its x,y position, if my phone's compass work in the same environment?
I am using hmc5883L on an autonomus robot. It shall remain in a 1 meter squared area. I have recently discovered that its reading changes up to 20 degrees on different positions even when it is facing ...
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Calculating absolute roll/pitch/yaw angle of falling objects [duplicate]
I am wanting to build a device with gyro, accellero, gauss (compass) sensors and barometric sensor.
This device will record all data from the sensors over a period of about 15 minutes where a person ...
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Calculating a compass angle?
I am getting data from compass( hmC5883L) and trying to detect angle.
Well, i dont really care about offsets, i just want to check that if its flat on the table ...
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Why also using magnetometers in IMUs?
Why do we also use magnetometers when building IMUs, that is why don't we simply and only use gyroscopes and accelerometers?
I also would like to know how does a magnetometer work as a 3-axis device? ...
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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 ...
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Electronic compass, RF and batteries
I am currently working with a project where i am creating a small embedded board consisting of a 9DoF IMU which is transmitting its data with RF (BLE or normal RF). Furthermore there will be a battery ...
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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 ...
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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 ...
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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 ...
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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 ...
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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.
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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 ...
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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.
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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 ...
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What is/are the minimum sensor(s) is needed to get inclination/tilt/pitch of project with roll compesation?
I am planning a project that will measure and log the tilt of my push bike while I am riding it. The fastest that I would be recording is every 0.1 seconds, though it will probably be every 1 second. ...
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Electronic compass soft iron distortion
I'm making a small autonomous vehicle, it is about 300x300mm in size.
I need to get a heading for the robot.
I currently have a CMPS03 compass but am finding that it is highly sensitive to soft iron ...
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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 ...
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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 ...
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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? ...
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