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Tesla has applied for a patent for a new electromagnetic windshield-wiper system

caranddriver.com

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Re: Tesla has applied for a patent for a new electromagnetic windshield-wiper system

#111

Post by simias »

userbinator wrote: post #29

Tesla mentions that the mechanical components of the traditional wiper blade create a lot of friction, which requires more power to the motor that moves the arm back and forth. I thought it was the friction of the wipers themselves on the glass that takes the most power... In any case, some research reveals that typical wiper motors are <50W, which even if that was reduced to 0, would be an insignificant fraction of…

I think it's fairly obviously mainly a marketing move. These wipers (judging by the drawings) look cool and futuristic. If they ever implement them I'm sure that's going to be the main motivation.

I can be very critical of Tesla but if there's one thing they achieved it's making electric vehicles that look cool. I don't think many teenagers saw a Prius as an aspirational vehicle but I'm pretty sure you could find Tesla posters in many a bedroom.

Re: Tesla has applied for a patent for a new electromagnetic windshield-wiper system

#112

Post by phkahler »

userbinator wrote: post #29

Tesla mentions that the mechanical components of the traditional wiper blade create a lot of friction, which requires more power to the motor that moves the arm back and forth. I thought it was the friction of the wipers themselves on the glass that takes the most power... In any case, some research reveals that typical wiper motors are <50W, which even if that was reduced to 0, would be an insignificant fraction of…

The maximum power of the car is not relevant to range. A Tesla uses between 200 and 300 Watt-hours per mile if I recall correctly. A Watt-hour (Whr) is a one watt load used for an hour. If it takes you 5 hours to deplete your battery, a 50W load for 5 hours will use 250 Whr. You will lose 1 mile of range because of it.

When doing motor control work and dyno testing, one of the challenges is measurement of mechanical power (and even electrical) because you need to measure up to -200kW but you care about differences of 10s of Watts.

Re: Tesla has applied for a patent for a new electromagnetic windshield-wiper system

#113

Post by jondumbau »

matt-attack wrote: post #100
Brakenshire wrote: post #86

Earlier quoted context omitted.

Hm, even LED TVs use something like 30W, don’t think you’d get much out of dimming a tablet sized screen. 50W for 5 hours is 250Wh, which is a mile extra range. That’s worth having.

What’s funny is all of these trade offs have always applied to ICE cars as well, but for some reason no one cares. Blasting your radio shortens your range even in a gas vehicle. Running your wipers shortens your range even in a gas car.

I'm not much for electronics. Can you explain how playing the stereo affects mileage?

Re: Tesla has applied for a patent for a new electromagnetic windshield-wiper system

#114

Post by fooker »

mkl wrote: post #94
NullPrefix wrote: post #77

Earlier quoted context omitted.

Are you implying that horses are not a viable form of transportation?

In modern cities, and for the large majority of car uses, horses are not a viable form of transportation.

Cars are not particularly suited to modern cities either.

Re: Tesla has applied for a patent for a new electromagnetic windshield-wiper system

#115

Post by wffurr »

jondumbau wrote: post #113
matt-attack wrote: post #100

Earlier quoted context omitted.

What’s funny is all of these trade offs have always applied to ICE cars as well, but for some reason no one cares. Blasting your radio shortens your range even in a gas vehicle. Running your wipers shortens your range even in a gas car.

I'm not much for electronics. Can you explain how playing the stereo affects mileage?

Additional power draw on the accessory circuit places increased load on the alternator which in turn causes the engine to run a little harder than it otherwise would. Thus burning a little extra fuel.

Re: Tesla has applied for a patent for a new electromagnetic windshield-wiper system

#116

Post by mikro2nd »

Scoundreller wrote: post #84
hadlock wrote: post #67

Earlier quoted context omitted.

Silicone wipers naturally leave behind a thin silicone film on the glass. Once this film is in place, the water serves as a pretty decent lubricant so long as it's raining.

I’ve found that a windshield at a shallow angle and RainX can negate the need for wipers at high speeds.

Much more significant to me is the clear vision it affords when you come up behind a large truck/semi in wet weather. Makes passing at least possible, as opposed to being stuck, unable to pass, in a cloud of dirty water for long stretches of time.

Re: Tesla has applied for a patent for a new electromagnetic windshield-wiper system

#117

Post by jondumbau »

wffurr wrote: post #115
jondumbau wrote: post #113

Earlier quoted context omitted.

I'm not much for electronics. Can you explain how playing the stereo affects mileage?

Additional power draw on the accessory circuit places increased load on the alternator which in turn causes the engine to run a little harder than it otherwise would. Thus burning a little extra fuel.

Cheers, alternators are essentially magic to me. Id have presumed they were generating 'enough' power at all times the engine was running.

Re: Tesla has applied for a patent for a new electromagnetic windshield-wiper system

#118

Post by Udik »

simias wrote: post #111
userbinator wrote: post #29

Tesla mentions that the mechanical components of the traditional wiper blade create a lot of friction, which requires more power to the motor that moves the arm back and forth. I thought it was the friction of the wipers themselves on the glass that takes the most power... In any case, some research reveals that typical wiper motors are <50W, which even if that was reduced to 0, would be an insignificant fraction of…

I think it's fairly obviously mainly a marketing move. These wipers (judging by the drawings) look cool and futuristic. If they ever implement them I'm sure that's going to be the main motivation. I can be very critical of Tesla but if there's one thing they achieved it's making electric vehicles that look cool. I don't think many teenagers saw a Prius as an aspirational vehicle but I'm pretty sure you could find Tes…

The only possible thing I see of practical value in this solution is that it might (might, not sure I understood well) reduce the amount of moving parts and gears. Essentially the entire motion would be controller electronically, no gears or motors.

Re: Tesla has applied for a patent for a new electromagnetic windshield-wiper system

#119

Post by NeedMoreTea »

jondumbau wrote: post #113
matt-attack wrote: post #100

Earlier quoted context omitted.

What’s funny is all of these trade offs have always applied to ICE cars as well, but for some reason no one cares. Blasting your radio shortens your range even in a gas vehicle. Running your wipers shortens your range even in a gas car.

I'm not much for electronics. Can you explain how playing the stereo affects mileage?

In the old days of lower power alternators (or really old days of generators), and lower power engines, the revs would drop noticeably, and the note change, when you turned dip lights on, aircon or even occasionally - in smaller cars - the heated rear demister! Made it very obvious the engine was working harder.

Now that tickover and fuel injection is computer controlled or we have EVs, and there's a far heavier electrical load in all cars all the time, you never notice any more. They all take power, and decrease fuel efficiency.

Re: Tesla has applied for a patent for a new electromagnetic windshield-wiper system

#120

Post by balfirevic »

Udik wrote: post #118
simias wrote: post #111

Earlier quoted context omitted.

I think it's fairly obviously mainly a marketing move. These wipers (judging by the drawings) look cool and futuristic. If they ever implement them I'm sure that's going to be the main motivation. I can be very critical of Tesla but if there's one thing they achieved it's making electric vehicles that look cool. I don't think many teenagers saw a Prius as an aspirational vehicle but I'm pretty sure you could find Tes…

The only possible thing I see of practical value in this solution is that it might (might, not sure I understood well) reduce the amount of moving parts and gears. Essentially the entire motion would be controller electronically, no gears or motors.

Electronically controlled motion by means of magnetic fields is a motor.
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