# Tag Info

## New answers tagged sensor

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You are looking for an analogue to analogue signal conditioner. For industrial applications these are usually DIN rail mounted, 24 V power and feature opto or transformer isolation between the input, output and, in most cases, the power supply is isolated from both input and output. Most are configurable for 0 - 20 mA, 4 - 20 mA, 0 - 5 V and 0 - 10 V on ...

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Ok, your ring detector senses an AC signal on the 2.5mm jack. You need to make the infrared beam detector produce an an AC signal when the infrared beam is blocked so you need a circuit to drive the beam sender and a circuit that monitors the beam receiver and makes an AC signal (eg a noise-making circuit) when the beam receiver sees nothing.

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This is a dead end. It's easier to design a beam sensor-triggered flasher (DC, relatively reliable currents) from scratch than it would be to convert a piezo signal (very low currents, AC) sensing circuit. So use your break-beam sensors to trigger a flasher. There's a lot of "flasher circuits" out there, and it's also not hard to figure out how to amplify ...

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If you could answer why pulse induction does not discriminate (from technical perspective) that would basically be answer to my question. A pulse induction metal detector uses a single coil and a transmit/receive switch to connect said coil to either a transmit pulse or a receive amplifier. In some respects it’s like radar. What you get coming back from ...

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My guess is that by taking a big number of readings of the measured parameter will cancel out the sensor inaccuracy to some extent. Or am I wrong ? The law of large numbers (LLN) says that when averaging a large number of random variable realizations (here: measurements), the result will converge to the expectation of the underlying random distribution. You ...

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You always have two kinds or errors: Random error and systematic error Systematic errors are there always with the same amplitude, they don't change (over long periods of time and extanded temperature range they do have drift as well, this will be defined e.g. in ppm /°C or ppm /y). This means these errors won't cancel out with averaging, because all ...

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The easy way is averaging a large amount of samples. The better way is to evaluate the normal distribution and set a confidence interval say 95% .. Then discard the samples that aren't within that confidence interval of the normal distribution. I guess it is also worth taking the precision into account. Say if the accelerometer at rest measures 0.9g you ...

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Raspberry Pi GPIO should register 3.3V for a logic 1. Assuming the impedence looking into Pin22 GPIO 25 is infinite, Pin 12's voltage is a voltage divider. 1/11 or 1K/(1K+10K) of 5V = 5/11 = 0.45V << 3.3V (yikes!). Choose R2 (pull down resistor) that provides 3.3 volts and not 5/11 = 0.45V Seek: R1/(R1+R2) = 2/3 If we keep R2 = 10K, then change ...

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You have to constrain the output of TIP31 to be higher than 0V by (at least) a few mV, otherwise this analog computer can find the wrong solution. BTDTGTTS.

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The LM35 datasheet says absolute maximum rating for supply voltage is -0.2V. It means that connecting it the wrong way to a power supply can damage it, and it does not have to work any more as the absolute maximum ratings have been exceeded. Also the minimum recommended supply voltage is 4V, so check that your supply voltage is also 4.0V or more. It may ...

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You can calibrate the sensors with a measurement at x=170 using a power exponent to the interpolate the curve. Other errors may be due to hysteresis, loose connections or noise. I plotted the average to be $y(x)=-0.0000656*x^{2.573}, R^2=0.995$ But better results can be obtained curve-fitting with 2 or more measurements.

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Is there any reason one might want to measure both the primary and secondary coils on an LVDT? To get better accuracy is the usual reason. The amplitude is somewhat subject to noise perturbations so, if you also measure the phase angle between primary and secondaries you get a more reliable result. To do that you need to know what the primary wave form is....

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First of all, sensor TX pin is transmit output so it must be connected to RasPi RX pin which is a receive input - Connecting TX to TX is usually wrong. But in this case is not that simple, so don't do that just yet. The sensor TX output voltage levels are same as it's supply voltage, so it uses 5V logic levels. RasPi RX pin does not tolerate 5V logic levels,...

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It looks like the impedance is about 1K-2K through your band of interest. I don't know what you mean by "much more," but 20K input impedance for your preamp should probably be easily achievable, and 200K wouldn't be much of a challenge. Note that your internal resistance is significantly lower--almost negligible--but the impedance will still affect both ...

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All lasers put out a fairly wide "cone" of light. If you want a narrow beam, you have to put a lens on the end of your laser. Usually the manufacturers provide this automatically. If you want the natural beam, you have to ask for a laser which doesn't have any built-in lens. (Laser light is monochromatic point-source light. It need not be collimated/...

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The sensor has a programmable region of interest (ROI) that can be used to set the direction of the beam to some degree. I don't know if it works. I have only used the sensor for normal distance measurements. The readings you get from the sensor is quite accurate if configured correctly. It becomes even better if you add a special cover glass. You don't ...

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One solution is to use an industrial position sensor. Sick, for example, make a range of magnetic cylinder sensors up to 500 mm long and these sense the position of a small cylindrical magnet on the object being monitored. As is normal with industrial applications these will probably require a 24 V supply (I didn't check) and the analog output will be either ...

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Any ideas? Maybe (just maybe) you could engineer the equivalent to a linear voltage displacement transducer (LVDT). It uses three coils and a linear moving target to estimate position: - Conceptually it is the same as a food-industry three coil metal detector: - The thing about the metal detector is that the aperture design (the hole in which the product ...

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The bridge should be about 10% of the emitter voltage pulled up by your operating offset. This ought to be within the Vcm input range for desired output. But you can check that. As far as phase margin and reactive compensation , we'll leave that for another question.

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The solution is very simple, I was hinted at in the ST forum. It lacks ADC calibration. After adding the missing code, the reading is 30C, which means it's the expected one.

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I am afraid no one will be able to give you an ultimate answer, since your question has uncertainties regarding the accuracy you need and the time and cost budget for the project, but I can give some direction. Note, that impedance and capacitance measurement is not the same, and that you can't measure the capacitance with a DC voltage. For impedance ...

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