Society of Robots - Robot Forum
Electronics => Electronics => Topic started by: epicjr77 on April 16, 2008, 09:40:52 PM
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Has any one used this out doors? I am looking to put one on a 130lb bot and wondering how it would do.
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as long as there's no bats flying around, it should perform as specified.
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You should give it a try. You wouldn't be disappointed.
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yea the PING sensor will work outdoors
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Yea defiantly use the PING))). I went to a college last week and they had been working on a robot car. Low and hold when i got a closer look they had PING))) sensors on the side of it!
Bane
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The PING))) can be used outdoors noting the following:
it is not a water-proof device... do not expose to water.
Sound travels faster in warmer air than in cooler air, so depending on the outside temperature, you accuracy may be off a bit.
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I learn in physics that sound travels faster when cold because the molecules are closer together, i think. Just wonding
Bane
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Physics Lesson: Temperature and the Speed of Sound
Temperature is also a condition that affects the speed of sound. Heat, like sound, is a form of kinetic energy. Molecules at higher temperatures have more energy, thus they can vibrate faster. Since the molecules vibrate faster, sound waves can travel more quickly. The speed of sound in room temperature air is 346 meters per second. This is faster than 331 meters per second, which is the speed of sound in air at freezing temperatures.
The formula to find the speed of sound in air is as follows:
v = 331m/s + 0.6m/s/C * T
v is the speed of sound and T is the temperature of the air. One thing to keep in mind is that this formula finds the average speed of sound for any given temperature. The speed of sound is also affected by other factors such as humidity and air pressure.
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The speed of sound is also affected by other factors such as humidity and air pressure.
So can I read that to say altitude?
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I would think "yes" as altitude can result in a double whammy... less pressure and colder temperatures!
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it is not a water-proof device... do not expose to water.
lol
a bit obvious
also, I heard you can waterproof it using plastic spray (forgot what its called, something urethane)
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There is a guy in France who made a "Nautile" 1/8 scale driven by a picbasic2000.
He made a water proof sonar using MA40E7R as Rx and MA40E7S as Tx, from MURATA.
The circuit can be found here: http://arn.gui.free.fr/sonar.htm
The trials were done in a swimming pool .
If in need of some translation I can help
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So the sensor will work . . .
but suppose your robot drives up to a hill - your bot can simply drive up it, but it will appear as an obstacle in the way instead. Same for going down-hill, a change in slope could appear as an object in the way.
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Will need some kind of 3D radar, and a good interpretation of the "picture" to figure out if it's an obstacle or a slope ?
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it is not a water-proof device... do not expose to water.
lol
a bit obvious
also, I heard you can waterproof it using plastic spray (forgot what its called, something urethane)
poly-urethane? amyway, in science, we learnt that submarines use PING sonar and they go underwater so why not water-proof?
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amyway, in science, we learnt that submarines use PING sonar and they go underwater so why not water-proof?
Electronics and water don't mix. PING))) is the name of an ultrasonic sensor http://www.parallax.com/Store/Sensors/ObjectDetection/tabid/176/ProductID/92/List/1/Default.aspx?SortField=ProductName,ProductName
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i know that but ping is also the term for the frequency "ping" that ultrasonic devices send out and receive back. submarines have the emitters on the inside of the submarine so how does the sound get into the ocean without hitting the sides of the submarine and bouncing straight back?
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My guess would be that the sonar transducer is mechanically impedance-matched to the hull, so little reflection occurs. The hull wouldn't have to be pressure resistant where the sonar transducer is located. The transducer could be at ocean pressure. So you could have an impedance match between transducer, hull and water.
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it is not a water-proof device... do not expose to water.
lol
a bit obvious
also, I heard you can waterproof it using plastic spray (forgot what its called, something urethane)
it Tis a form of poly urethane, carfull to follow all saftey precations when using, very hasardouse to lungs if atomized or burnt but should work for this aplication. dont know for sure but it has no adverse affects with rf sigs (no i can not spell)