This idea is based on ericscottf's "Real Shift Indicator" and supercat's annotation to it.
For manual transmission cars, a touch sensor detects when your hand is on the gear stick. A tone based on the speed of the gearbox side of the clutch is then played through your stereo. When the two sides of the clutch are in sync, you will hear one note. When they're out of sync, you will hear a (probably displeasing) harmony between that note and the engine.
Hopefully in this way you will gradually learn the correct engine speed when shifting into a new gear, without taking your eyes off the road. When you've learned to shift perfectly, you can switch it off.
Since modern cars are quite good at isolating the engine noise from the cabin, you might need to amplify that as well when your hand is on the gearstick.-- Srimech, Feb 14 2008 Original idea Real Shift Indicator [Srimech, Feb 14 2008] Or could be a volume indicators that shows a need to increase or decrease RPM. When they're lined up properly the sound should become pleasant.-- normzone, Feb 14 2008 Too complicated, but [+], because "take out all that underfelt" could hardly be called an idea.-- Ned_Ludd, Feb 14 2008 Put an expereinced driver in the rear seat behind the driver. Equip same with a rubber mallet. Everytime the gears get crashed, the driver gets bashed on the bonce.
Cheap and effective.-- 8th of 7, Feb 14 2008 The use of the term harmony is correct. Mono works fine and they aren’t displeasing harmonies at all. You hear this harmony when you match engine speeds with an adjacent motor vehicle. I use it to tune twin engines on aircraft. Although we don’t actually hear it, we also use it to tune our TVs and radios (called heterodyning).
The solution can be found using trigonometry. The mixing of two frequencies creates a phenomenon called beat frequencies (Sum Rule). The Beat Frequency equals the absolute value of the difference between each frequency (F =|f1 –f2|).
Similar to your clutch problem, pilots of twin engine aircraft (or boats, two cars, etc) can match the engine speeds by listening to their resulting beat frequency. Radically different frequencies produce higher tones (frequencies), but as the frequencies begin to match or equal (f1 = f2), their beat frequency reduces to zero. When approaching a match, the additional extra frequency begins makes a undulating hum or slow drone.
It’s guaranteed to lull one to sleep. Keep the switch on the gearstick!-- CwP, Feb 14 2008 I'm being a snarky jerk, but:
What tone represents the clutch when the car is at rest?
In my experience, people's greatest difficulty learning to drive a stick is getting the car going; synching speed with a tranny that's already moving isn't too hard since it it the clutch's job to absorb small disparities.-- elhigh, Feb 15 2008 To teach someone how to start a car in first gear from zero mph: Sit them in the driver's seat and tell them they have to get off the clutch without using the gas at all. This teaches them about the engagement points (Sometimes referred to as "friction zone") and how once you're moving a little, that doesn't mean "get off the clutch fast now". Teaching someone how to shift properly without a large disparity between ideal RPM and current RPM is something that needs to be done, as it is possible to learn that wrong and keep doing it wrong.-- ericscottf, Feb 15 2008 "What's this damn irritating sound that keeps interrupting my stereo?-- RayfordSteele, Feb 15 2008 Wouldn't a noisemaker on the clutchplate that scrapes against the flywheel do exactly the same thing? Silent when the clutch is engauged and when you are rev matched and producing two distinct tones for the direction of the rotation. Possibly a custom item for driving schools. It would need to be loud.-- WcW, Feb 16 2008 Using a sound would allow the instuctor to point out exacly when the error occured. By functioning only on the clutch level it would help with starting from stopped. It would not teach double clutching. (that's ok)-- WcW, Feb 16 2008 random, halfbakery