Extra Accelerator and Brake pedals installed in the back seat of a cab.
Two types. Working and Not Working
Every time you step on the nonworking brake pedal because your scared something special should happen inside the cab just not sure what exactly. Maybe you get a discount ?
These non working pedals will record passenger useage so that a profile can be constructed and measurement can be made of the drivers consistent performance.
Depending on the over time results the pedals are either removed or made to function.
Every time you step on the fully functional accelerator or brake pedal the result is acceleration or deceleration. The working pedals override the drivers use of the corresponding devices.-- vfrackis, Jul 10 2013 This seems like a rational, well thought out proposal with no obvious problems.-- MaxwellBuchanan, Jul 10 2013 Every so often, a (typically elderly) person driving a car will smash it through a shop window due to accelerator/brake confusion. They are subsequently encouraged to consider taking cabs.
This would bring the joy and excitement of accelerator/brake confusions back into their lives.
And the gibbering terror of the passenger override proelling them into oncoming traffic into the lives of cabdrivers. They do go on, but it seems a bit much, doesn't it?-- gisho, Jul 10 2013 I don't see much chaos being generated by those pedals. Perhaps one could be connected to a computer that randomly activates various devices in the cab. The lights. Or maybe a sproinging boxing glove, directed at the passenger. Or ...-- Vernon, Jul 11 2013 [+] Good idea. The fake brake could cause the seat belt to tighten a little bit and the accelerator could make it a little bit looser. Rear speakers could emit tire screeching noises activated by the pedals.-- cudgel, Jul 11 2013 The brake pedal could signal the cabbie you want to go slower therefore his meter could run longer. The gas pedal could make the meter go faster thereby charging you more money, but not getting there any quicker.-- xandram, Jul 12 2013 random, halfbakery