Automatic Wipers are magic

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bernie
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Automatic Wipers are magic

Post by bernie »

Had a trip to Chippenham today, bloody raining all the journey[:(][:(][}:)][}:)], but those auto wipers on my Xant are just bloody marvellous.[:)][:)][:)]
Any idea of the technology behind them, rain sensor etc?
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tonyb1
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Post by tonyb1 »

But doesn't it spoil the excitement of seeing how far you can go before having to turn them on...lol. 'This system uses a sensor that basically consists of two sets of contacts separated by an insulator. When water falls on the sensor, the water conducts a signal that alerts the system to water on the sensor'. Copied from a site I was looking at, hope it helps.
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Post by jeremy »

One of the rain sensors works by an infra red? emitter surrounded by sensors. This is attached to the windscreen and in the dry the output form the source is reflected back by the outer glass layer and received by the sensors. A drop of rain prevents the internal reflection, one sensor ceases to conduct and the wiper operates. Nice!
I must have a go at making one!
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nick
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Post by nick »

Some of them seem to use an optical system now, certainly the Pug 206 I had as a courtesy car a while back did. If you looked from outside with it switched on you could see an infrared bulb flashing faintly in a box above the mirror.
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Post by bernie »

<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by nick</i>

If you looked from outside with it switched on you could see an infrared bulb flashing faintly in a box above the mirror.
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Blimey, Amsterdam on wheels[:D][:D]
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Post by andycarter »

Never had a car with auto wipers; so here's the dumb question to start with..
a) what stops them coming on when you're driving through a car wash?
b) assuming the answer to (a) is 'a switch' then they're only semi-automatic[:p]
c) why not do away with optical sensors and just measure the power draw of the motor - dry windscreen draws more power than a wet windscreen.
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AndersDK
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Post by AndersDK »

Ever noticed the large pile of ripped wipers at car washes ? [:p]
Naa - as I understand it the auto wipe is "armed" like a timer wipe setting on the wiper switch - Bernie ?
Once the area with the sensor is wiped (by the wipers [;)]) - the sensor will set the wipers off. Not that complicated to build for the hobby electronics enthusiast.
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Post by bencowell »

<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by andycarter</i>


c) why not do away with optical sensors and just measure the power draw of the motor - dry windscreen draws more power than a wet windscreen.
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When the screen is dry, how would it know when to start unless the motor is always trying to "pull". Would the motor burn out quicker?
You would need some calibration for different wipers or screen washes.
You have to look through the glass, why not let a machine look for you?
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Oystercatcher
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Post by Oystercatcher »

<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by andycarter</i>


a) what stops them coming on when you're driving through a car wash?
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On the Xant, the 'auto' setting is position 1 on the stalk, ie where the intermittent setting would be on an ordinary setup. In a car-wash you just switch them off [:)]
<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote">
b) assuming the answer to (a) is 'a switch' then they're only semi-automatic[:p]
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True. Also, you need to 'arm' them. When you first switch on, they give one wipe.
Bloody handy, though mine occasionally play up. If they go into continuous mode, they sometimes don't revert to intermittent when the rain eases off. Cleaning the oily cr*p off the screen helps, as did cleaning the haze off the inside under the sensor.
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Post by mpr1956 »

Hi bernie, I live in Chippenham, and I think I needed Hydroplanes today for the standing water!! Hope you enjoyed your visit, now that those works on the rail bridge have finished and the traffic is moving again.
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Post by jeremy »

here's a description of how one works:
http://www.raintracker.com/how_RT_works.htm
and its available for £118 + VAT http://www.accessiblevans.co.uk/rain.htm - + fitting.
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bernie
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Post by bernie »

<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by mpr1956</i>

Hi bernie, I live in Chippenham, and I think I needed Hydroplanes today for the standing water!! Hope you enjoyed your visit, now that those works on the rail bridge have finished and the traffic is moving again.
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I went up, from Southampton, via Salisbury and Divizes caught behind countless dustcarts and lorries washing me with spray. Awful journey.
On the way back I went via the M4 and Newbury, another mistake.
M4 J17 to J16 one lane closed both ways because of an accident.
Not a pleasant days motoring[:(]
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Post by bernie »

<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by AndersDK</i>


Naa - as I understand it the auto wipe is "armed" like a timer wipe setting on the wiper switch - Bernie ?
<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">
Yes position 1 for auto wipers.
The thing that make them brilliant is that you can leave them on.
With light dizzle they flick every 30seconds or so, light rain every 1 to 15 seconds but if you overtake a lorry with clouds of spray they go into super fast mode until the screen is clear.
When it stops raining they stop.
All this without touching the wiper on/off control.
As i said bloody marvellous[:)]
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Post by bernie »

Was it bin emptying day yesterday in Chippenham mpr1956?
Lots of dustcarts.
mpr1956
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Post by mpr1956 »

Hi again Bernie... They were either probably catching up after Easter, or they knew you were coming!, as friday is normally (wheelie) bin day. The traffic generally was exceptionally bad I agree . I am very impressed that the automatic wipers work as they should... Sometimes advanced technology really is the answer!!.
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