Recent content by p1ayaone1

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    Open Call: propose a CubeSat payload

    To the good people of PF, I've been working an a few satellite design projects at school, and we are just getting started on one that might actually be launched (in about two years time). We have lots of ideas, but we're all electrical, mechanical, and computer engineers, and our thinking...
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    Is a Vibrating Structure Gyroscope the Key to Measuring Vehicle Pitch and Roll?

    And accelerometers measure strictly translational motion, not rotational.
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    Is a Vibrating Structure Gyroscope the Key to Measuring Vehicle Pitch and Roll?

    No. Angular rate gyros measure angular acceleration. That is not how fast you are rotating, but how much the rate of rotation changes. If you would like to know the angular position (the inclination) you need to double-integrate. Integrating the acceleration once gives you the angular rate...
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    C/C++ How to calculate rotation, divergence in C/C++

    Unfortunately your program won't be very simple! Unlike a 4-th generation language such as Matlab, C++ does not natively support mathematical objects such as vectors. You'll need at least to write a "Vector" class, and define your operators (div, curl, etc) based on that. You might be...
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    Other Becoming an Engineer: Considerations and Personal Experiences

    You'll do great because: 1. You found this forum 2. You used the following words in your post: "fun", "fascinating", "love", "fulfilling", "progress", "potential" Don't worry about the math. They will drill you over and over on all the little tricks you need to (eventually) solve more...
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    What does it take to use a usb?

    I'm more familiar with Atmel's ARV microcontrollers, so here's my proposal to make an audio-recording device: If you want removable storage, pick up an SD card breakout board. SD is a little easire to connect to an MCU since it doesn't need any drivers or ontrollers, just a handful of pull-up...
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    Inductorless DC-DC converters for space application

    I got that 12 C meant 12 deg Celcius, I meant what body has that temp? The Earth? So what you're saying is that the side of the satellite facing the Earth will have the same temperature as it? If I've understood, then the side of the satellite facing the Sun will have the same temperature as...
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    Inductorless DC-DC converters for space application

    Thank's not to say the temp is 0K, but temperature is a property of matter, of which there is very little floating around at ~800km.
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    Inductorless DC-DC converters for space application

    Sorry, I don't understand. What is 12 C? The actual temp of the satellite will depend on how much solar radiation is absorbed/reflected. There is no ambient temperature in space afaik.
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    Inductorless DC-DC converters for space application

    https://www.physicsforums.com/showthread.php?t=345524&highlight=lithium-ion A quick read over this thread seems to indicate that charging LiIon in extreme cold might be dangerous, but I suppose that's not a problem. I could of course throw the circuit in the freezer, but maybe I'll just wait...
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    Inductorless DC-DC converters for space application

    Your assumption (5 sides x 4 modules) is correct, I will update the schematic to make it more clear. Originally I had a large number of 0.5V cells in series, and I had bypassed those with diodes. I though that non-illuminated PV cells act like open circuits. The design was modified to...
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    Inductorless DC-DC converters for space application

    It does have that nice feature, but it's disabled (the TS (temp-sensing) pin has been set to Vcc/2). The reason is this: Ok, the battery is hot. Now what? Switch it off, and the whole satellite dies. Leave it on, and the battery burns out, and the whole satellite dies. There is also a...
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    Why do we have to learn that?

    Maybe, but someone still needs to build the expert system
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    Extracting yaw, pitch, roll from transformation matrix

    Craig's book on robotics (the title is either "Introduction to..." or "Fundamentals of...") has a nice treatment of moving back and forth between transformation matrices and poses (x, y, z, rx, ry, rz), as well as a detailed explanation of the 12 sequences. It was a good starting point for me...
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    Why do we have to learn that?

    If we stopped teaching calculus today, who would write the new versions of Maple tomorrow?
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