Recent content by AppleBite

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    How materials breaks

    What you are describing is an entire academic field called Fracture Mechanics, covered by many engineering courses. The field is vast, and the process of fracture will depend on the material, loading and test conditions, etc. Start with this link, and there are also numerous books and papers on...
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    Engineering Competitions like DARPA?

    There are also a number of Micromouse competitions worldwide, which cover a broad range of engineering disciplines.
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    Converting uniformly distributed load applied to a surface on an angle to point loads

    Have you tried calculating the resultant force of the distributed force (which by the looks of your drawing will be at the middle joint, in the -y direction) and then calculated the forces in each truss due to the resultant force? Remember, the moment caused by a distributed force can be...
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    Need help with arduino sampling voltage and current

    No worries! Well, what serial functions are you using at the moment? An easy, but slow, method that I sometimes use when I need to graph data is to use the Serial.println( ); function, and then simply graph the data I get versus time in some other software (Excel)
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    How a vacuum works

    This should also be helpful:
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    Inflate aluminium tube to increase it’s strength?

    Also, it will depend on the loading on the beam. Pressurizing the thin walled tube induces axial and hoop stresses. Thus you increase it's compression strength in the axial direction, but be very careful that the hoop stresses are not increased so much that you exceed the yield strength causing...
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    Need help with arduino sampling voltage and current

    Sounds like you want to do some analog input sampling. Remember the Ardunio can only measure inputs between 0-5V, so you want to design a circuit with a voltage divider and some diodes to ensure that the input to the Arduino never exceeds the value it can take (trust me, you'll fry the thing if...
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    I want to do an egg drop by submerging the egg in fluid. Which fluid is best?

    Also, you'll want to ensure a high enough viscosity of the liquid to ensure that the egg does not hit the bottom of your container at a high speed. Thus I would test a high viscosity liquid with significant buoyancy. Hence, basically your egg would only be submerged on impact, but not so much...
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    Rate of energy release by Polonium-210

    "Activity" (in Bq) is the number of nuclei that decay per second. "Energy" is defined as the energy per nucleus released. As defined in the answer here, the units after the conversion will be in joules (MeV * 1.6 × 10-19 = Joules). Hence, (number of nuclei / second)*(joules / number of...
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    C/++/# C++ Problem with accessing elements of a character

    Thanks guys. Indeed, I was quite confused about characters and character arrays, but I think I've sort of got the hang of it now. Also: This solved my issues with reading the correct data, as without the 'NULL' the software just kept on storing garbage into my fx, fy and fz arrays.
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    C/++/# C++ Problem with accessing elements of a character

    I'm still having a few problems though. The output to "buff" is: <error>,xxxxxx,xxxxxx,xxxxxx,xxxxxx,xxxxxx,xxxxxx<cr><lf> Now, what I'm trying to do is the store each of the "chunks" of data between the commas into separate chars. However, using the code above, buff[i+2]; does not seem to...
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    C/++/# C++ Problem with accessing elements of a character

    Hey guys, I'm having trouble with sampling data from a force/torque sensor. I'm using Serial Com to receive the readings from the sensor, which is stored in a character of with 45 individual elements. What I'm trying to do is to pick out pieces of these data and store them separately. I'm...
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    Space in plastic to fit a ball bearing?

    It all depends on the type of fit you are looking for, and the available tolerance for the drilling of the hole. If you are going for an interference fit, it's probably safe to assume that the plastic will be compliant enough for a less than 10mm hole (again, this all depends on the tolerance of...
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    How can we combine metal and fiber together?

    Are you talking about a sheet of metal (steel or aluminium?) and a sheet of CFC? In that case some form of epoxy should work. Best results would obviously be achieved if you use the epoxy on overlapping faces of the sheets, i.e. not end to end. This wille depend on the expected loading...