urgent plz

Actually i ve bought several ardupilot mega with imu shield, but i ve received all the components without any documents, so actually i cant read the correct angles from the imu, even after i download some codes such as apm_imu_test.zip, i got the same problem.... i read data from the imu but not correct, i mean when i rotate the imu the corresponding values dont match with the rotation angle,..... i hope u can support me with any help, BTW this is the second time i send u questions without any reply.......im really upset from the technical support beside i guess i ll cancel my next orders if i cant resolve this basic problem.......i m asking too, if u r selling only rate gyros they r every where.... i thought u provide imu with calculated and accurate Euler angles............

regards

ahmed,

Egypt

Ahmed,

I am just a guy, like you, who experiments with these tools. I think maybe it is not fully understood that this is a community of people who are not purchasing functioning commercial products but rather raw tools, building blocks, and parts. Then we build what we want, using those tools, and share information so that other people can build similar things. But maybe you understand that. In any case, clearing that up does not help you with your question, so I will try my best (but remember, I am just another guy like you, and there are a lot of people here with a lot more experience than me.)

My understanding of the IMU is that it is essentially a breakout board, with lots of sensors and other useful things for use by two things, the ArduPilotMega hardware, and whatever software you decide to run (or write and then run) on that hardware. For example, if you want to have an AHRS (http://en.wikipedia.org/wiki/Attitude_and_heading_reference_system) then you can have that, but you have to write (or use existing) software. The IMU has gyros, and it has accelerometers, and you can add a GPS, but by itself, without software, it is not providing Euler angles and navigation solutions. If you want to make a weather station from it, you can do that too, add a sensor to detect windspeed and temperature, you already have a barometer, but you will need to have software.

Now, software does exist already for this hardware to calculate Euler angles and to make this an AHRS, and more even than that. The excellent ArduCopter and ArduPilot software are examples which you can use as it is, or that you can use parts of if it does not work how you want it too. In fact, I expect if you just want an AHRS, both of these do a lot more than what you might want. But even if that is the case, I recommend you try them, and this is why I recommend it.

A large number of the people who use the IMU are using it with one of those two versions of software. So you will get the best experience if you also try it. That way, you can ask questions and the other people may have answers.

For example, if you are not confident that the IMU is providing good gyro or acceleration output, here is the best way to test, first load Mission Planner, then load the ArduPilot or ArduCopter firmware. Connect to the APM with Mission Planner, go to Terminal (it will ask you to change to CLI) and type "test" then "imu" or "gyro" and rotate the board. You should see data that you expect. If not, check to see if you know which way is X, Y, and Z. If it is not working how you expect, copy/paste some data or make a video and I think people can help.

If you want AHRS, you will find all the code in ArduPilot or ArduCopter that does all the calculations you want. What is better about a community and projects like this, is for a commercial project, if the AHRS does not work how you want, then it is all you get. But here, you can change things to work how you want, add features you want, and add features that someone else made, but modify it for your needs.

Good luck, I hope that helps at least a little. I hope I understand what you are asking, but I assume that I do not, so be patient with me. We are all just ordinary people like you. Some people have companies, but most are doing this for a hobby, and are enjoying building new things that are different, not assembling the same commercial product as everyone else.

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Moderator

Michael Pursifull September 13, 2011 at 6:05am

Ahmed,

I am just a guy, like you, who experiments with these tools. I think maybe it is not fully understood that this is a community of people who are not purchasing functioning commercial products but rather raw tools, building blocks, and parts. Then we build what we want, using those tools, and share information so that other people can build similar things. But maybe you understand that. In any case, clearing that up does not help you with your question, so I will try my best (but remember, I am just another guy like you, and there are a lot of people here with a lot more experience than me.)

My understanding of the IMU is that it is essentially a breakout board, with lots of sensors and other useful things for use by two things, the ArduPilotMega hardware, and whatever software you decide to run (or write and then run) on that hardware. For example, if you want to have an AHRS (http://en.wikipedia.org/wiki/Attitude_and_heading_reference_system) then you can have that, but you have to write (or use existing) software. The IMU has gyros, and it has accelerometers, and you can add a GPS, but by itself, without software, it is not providing Euler angles and navigation solutions. If you want to make a weather station from it, you can do that too, add a sensor to detect windspeed and temperature, you already have a barometer, but you will need to have software.

Now, software does exist already for this hardware to calculate Euler angles and to make this an AHRS, and more even than that. The excellent ArduCopter and ArduPilot software are examples which you can use as it is, or that you can use parts of if it does not work how you want it too. In fact, I expect if you just want an AHRS, both of these do a lot more than what you might want. But even if that is the case, I recommend you try them, and this is why I recommend it.

A large number of the people who use the IMU are using it with one of those two versions of software. So you will get the best experience if you also try it. That way, you can ask questions and the other people may have answers.

For example, if you are not confident that the IMU is providing good gyro or acceleration output, here is the best way to test, first load Mission Planner, then load the ArduPilot or ArduCopter firmware. Connect to the APM with Mission Planner, go to Terminal (it will ask you to change to CLI) and type "test" then "imu" or "gyro" and rotate the board. You should see data that you expect. If not, check to see if you know which way is X, Y, and Z. If it is not working how you expect, copy/paste some data or make a video and I think people can help.

If you want AHRS, you will find all the code in ArduPilot or ArduCopter that does all the calculations you want. What is better about a community and projects like this, is for a commercial project, if the AHRS does not work how you want, then it is all you get. But here, you can change things to work how you want, add features you want, and add features that someone else made, but modify it for your needs.

Good luck, I hope that helps at least a little. I hope I understand what you are asking, but I assume that I do not, so be patient with me. We are all just ordinary people like you. Some people have companies, but most are doing this for a hobby, and are enjoying building new things that are different, not assembling the same commercial product as everyone else.
3D Robotics

Chris Anderson September 13, 2011 at 4:35am

I'm afraid I don't understand. Are you having trouble with any of the supported software (ArduPlane or ArduCopter)? If so, please give a version number and post a screenshot or error messages.

If you're not getting responses, it may be because nobody can understand your question.

This reply was deleted.

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urgent plz

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