<<  <  Page 2/7  >  >>
Charles Murray
User Rank
Re: NHTSA to brake unintended acceleration
Charles Murray   5/11/2012 6:29:49 PM
Regarding the effect of BTO on race driving, Toyota has sent us this: "If the brake is pressed first, followed by the accel pedal, BTO does not engage. This allows for hill starts...Also, for those double-footed drivers, BTO won't engage because the system can differentiate between intentional accel pedal input and a stuck pedal. If the APPS detects accel pedal movement, it assumes the pedal is not stuck and the driver is intentionally pressing both pedals."

Bud B
User Rank
NHTSA to brake unintended acceleration
Bud B   5/11/2012 3:56:54 PM
This device could be hazardous for high performance track driving.  It is standard practice to blip the throttle under braking to accomplish downshifting a couple of seconds before corner entry.  A decisive turn in under braking rotates the car to quickly line up to the corner apex.  Brake release and throttle application transfer weight to the rear wheels and stop the rotation.  Without throttle response, a spinout is probable.

Hopefully, if this device is imposed upon us, it will be user selectable, like the ESP (electronic stability program) in my Audis.  The ESP inhibits my inputs when going quickly; thankfully it can be turned off for track driving.

User Rank
A better idiot...
kf2qd   5/11/2012 9:55:34 AM
Reminds me of the old saying - Find a way to idiot proof it and all they will do is invent a better idiot...

Cars, and a lot of other stuff in life, are a potentially dangerous object that we have gotten used to and complacent with. And we live in a society where everything is someone elses fault. How long until one of these "throttle cutoff" devices fails on someone traveling on the expressway in high speed rush hour traffic and causes a multicar pile-up? All of these proposals need to be examened with a large dose of pessimism before they are foisted off as the next quick fix.

I still think the problem is there are too many loose nuts behind the wheel.

User Rank
Re: Unexpected interactions, accelerations.
Droid   5/11/2012 8:56:33 AM
Most industrial machines I've seen have a large and conspicuous red e-stop (emergency-stop) button.   Why not put on on a car.

User Rank
Re: Unexpected interactions, accelerations.
curious_device   5/11/2012 1:43:28 AM
The NHTSA doesn't appear, to me, to be an unbiased organization.  They did a sloppy job of investigating the possible electronic and firmware related fault conditions.

Even though further examination did find tin whiskers in some of the Toyota sub assemblies, the NHTSA is continuing to turn a blind eye.


Other automobile safety organizations agree that this is unsafe.


I agree completely with William K.  A start/stop button that flips a bit in a controller is NOT adequate to ensure operator control.

Automotive designers should be forced to study the THERAC case history and then defend why their operating environment is free from such safety concerns.

William K.
User Rank
Unexpected interactions, accelerations.
William K.   5/10/2012 11:45:58 PM
The very first thing that the NHTSA should do is forbid the sale of any car that does not have a positive means of shutting off the engine. That very specificly would not involve any computer in the shutoff process. I am talking about switching off the ignition power and probably the injector power as well. 

The very stupidest thing ever done in a car was to have one button for both start and shutoff. IT may be OK for a light, but it is a very poor choice for a vehicle. I have had instances of throttle sticking wide open, and switching off the ignition saved my hide every time. But in a car where the only option was to task the computer to switch off the engine, and the computer deciding thatit had to keep the engine running because you were in motion, would be a disaster in progress.

So I must conclude that either the NHTSA is not thinking very well, or else they have been paid to ignore the situation. Either way, the lack of a positive engine shutoff means is an inherently unsafe condition.

User Rank
Re: second thoughts
MYRONB   5/10/2012 7:33:46 PM
For guys engaged in a stop light "grand prix," a brake-throttle interlock would prevent the ability to rev the engine up in its torque band while taking slack out of the drive train before launching.  Yeah, I can already hear the comments of wasting gas, tires, stressing the car, etc., etc., but hey, it's fun and besides, I like to check my reflexes when the stop light changes.  But, all kidding aside, all these fixes are crutches for incompetent drivers, and are subject to failures that may leave the hapless driver and car exposed to injury and damage because the expected safety feature (crutch) didn't function.  As the old saying goes, you can make anything fool-proof, but not damnfool-proof.


Myron (Curmudgeon) Boyajian

Charles Murray
User Rank
Re: second thoughts
Charles Murray   5/10/2012 6:44:03 PM
I agree that the real usefulness of this systems is pretty negligible, ChasChas. I think the automakers like the idea because it gives them a legal leg to stand on in these cases. Unfortunately, the situation you describe -- wherein the driver stands on the accelerator while assuming he/she is on the brake pedal -- won't be remedied by this. The electronic control system can tell if you're pushing on the brake, but it has no way of knowing if you're just confused.

User Rank
Re: This would essentially ban heel/toeing
cwins   5/10/2012 5:58:26 PM
Kind of 37 seconds ago.  Enthusiast cars are already chipped and or driven with the laptop hooked up to the car's computer. The rest drive Camry's and step on the gas when they need to employ the BRAKE. OBTW saw the Google autonomous Prius driving itself on public roads with humans on board, now that's cool. 

User Rank
second thoughts
ChasChas   5/10/2012 4:57:06 PM

The unintended acceleration accidents around here happened when the accelerator was depressed while thinking they were pressing the brake - a panic situation.

I remember watching a guy come shooting through a car wash door and down a ravine - wasn't hurt. He thought he was cramming the brake down - hard!

One snowmobile driver broke a throttle cable and temporarily hooked the brake cable to the throttle to get home (the cables were alike on these older machines). He didn't get out of the parking lot and he smashed into a car - he said it was impossible to prevent no matter how he tried to tell his brain to think differently - wasn't hurt.

So when your brain has it's mind made up, sometime you just have to ride it out.

I don't think this "safety feature" has merit.

<<  <  Page 2/7  >  >>

Partner Zone
Latest Analysis
When you think of the DARPA Robotics Challenge, you may imagine complex humanoid contraptions made of metal and wires that move like a Terminator Series T-90. But what actually happened at the much-vaunted event was something just a bit different.
The machine is claimed to be the largest and most powerful electric pipe-bender on the market, exerting nearly 500,000 lb-ft of torque.
Traditional dev kits are based on a manufacturer’s microcontroller, radio module, or sensor device. The idea is to aid the design engineer in developing his or her own IoT prototype as quickly as possible. A not-so-traditional IoT development kit released by Bosch aims to simplify IoT prototyping even further.
This consulting firm has put together a report detailing the growing biomimicry design field in the US and around the world, from naturally bacteria-repelling surfaces to keratin-inspired polymers.
Here's a list of engineering and tech jobs ranked by outlook, work environment, stress, and income.
Design News Webinar Series
1/28/2016 11:00 a.m. California / 2:00 p.m. New York
12/8/2015 11:00 a.m. California / 2:00 p.m. New York
2/18/2016 11:00 AM PT | 2:00 PM ET
2/24/2016 11:00 AM PT | 2:00 PM ET
Quick Poll
The Continuing Education Center offers engineers an entirely new way to get the education they need to formulate next-generation solutions.
Jan 11 - 15, Designing ARM Devices Using Segger Tools
SEMESTERS: 1  |  2  |  3  |  4  |  5  |  6 |  7 | 8 | 9

Focus on Fundamentals consists of 45-minute on-line classes that cover a host of technologies. You learn without leaving the comfort of your desk. All classes are taught by subject-matter experts and all are archived. So if you can't attend live, attend at your convenience.
Learn More   |   Login   |   Archived Classes
Twitter Feed
Design News Twitter Feed
Like Us on Facebook

Sponsored Content

Technology Marketplace

Copyright © 2016 UBM Canon, A UBM company, All rights reserved. Privacy Policy | Terms of Service