| ??? 07/30/09 01:38 Read: times |
#168019 - Am I thinking in 2 Dimensions and you in 3D ? Responding to: ???'s previous message |
Kai Klaas said:
Well, the whole world once learned from you the "zero", so it might be over-hasty to say anything bad about this notation... Well, they better do. Otherwise, I have to propose this to the world committee of mathematics :-D Kai Klaas said:
Take care with the words "upward acceleration" and "downward acceleration". It's correct, if you mean the additional acceleration vector also acting on the reference mass. But the method to make the reference mass feel this acceleration is quite opposite! To make the reference mass feel a downward acceleration of 2g you must accelerate the rocket upwards by 1g! Yes you are right. I got the concept better now. I had a confusion about this which got solved. Kai Klaas said:
Well, additionally measuring the centrifugal acceleration isn't probably of much interest, so take only one ADXL202, put it at the center of mass, read out the x and y signal and compare with the g vector to find out the roll and pitch tilt angles. The ADXL202 mounted at the center of gravity is immune against centrifugal accelerations anyway. I will try to think about this more. I don't quite understand how with putting one accelerometer at the center of a flying robot (if this was what you meant)it would be possible to neglect the upward/downward acceleration and proceed to getting the angle directly. Maybe I am oonly considering 2 dimensions. Kai Klaas said:
Why the authors have used two ADXL202 they don't even know either probably... Perhaps so, I think I kinda remember other quad rotor projects using more than one accelerometers along Gyros. Have to go through them again more carefully to see the reasons for that. Thanks a lot for your help and time. I will have to think more as I said and come back with possible questions, Farshid |
