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Ford Engineers Test 'Predictive Logic' To Improve Cruise Control
cartechboy writes "Sometimes what we think of as 'car tech' is colored by sensational coverage of things like autonomous cars. But real engineers are working behind the scenes every day to make existing auto technologies more efficient. Take cruise control: Today, even adaptive cruise systems just throttle up when the car's speed drops and ease off when speed rises or a car gets too close. Today's cruise-control systems aren't predictive--meaning they don't plan ahead. At all. Now, engineers at Ford are adding predictive algorithms and more sophisticated powertain mapping to reduce the built-in overcompensation that ends up wasting fuel. Ford has mapped each vehicle's powertrain in much greater detail, and their prototype control systems look at grade steepness, load on the engine, and other variables every few seconds to predict what's likely coming up. Will the hill level off soon? Will the driver ask for more gas, or let up on the accelerator? Down the road, connected-vehicle and cloud-based data will build on these predictive developments--as will those autonomous vehicles you hear so much about. Think of this as a building block to the future."
Its not the cars who drive that way, its the Drivers. (And to an extent, under powered trucks who decide to occupy all lanes passing each other in precisely those locations where they obstruct everyone).
Basic Cruise Control from the 60s and 70's could handle that situation. The problem is there are too many people who won't use cruise control, and too many entry level vehicles that don't have cruise control (it cost a couple hundred bucks for after market kits, and less if you buy it included in a new car).
Modern Adaptive Cruise control will keep pace with a preceding vehicle (up to you set speed), and detect potential rear-end collisions long before the driver might.
Usually that costs much more because you need optics or radar (25ghz) to detect distance of the car in front. But it saves gas, collisions, and aggravation.
(I'll never own another car without adaptive cruise control).
Sig Battery depleted. Reverting to safe mode.
It's even more complicated than that. Cruise control is all too often a safety hazard on the interstate. Safety requires space, the more the better, between vehicles. All to often cruise control is the reason cars remain in close proximity, mile after mile. Sometimes a cruise control cretin will bogart the passing lane simply because his cruise control is oh so slowly allowing his vehicle to pass an only very slightly slower one. Safe driving requires constant adjustment of velocity in order to maximize space between vehicles. Driving safely is space and energy management.
The USA is only 4X older than me...perspective
"Honestly, officer, the car thinks I'm my wife going to a salon appointment, and the cruise control was trying to get me there on time!"
"The car sped up just as some blonde bimbo passed me in a Corvette convertible. I have no idea why..."
Seems like we all use the same roads... if we just log with altitude and accelerometer readings, we can make a 3d model of all the road surfaces, and layer this into the road database. Problem solved.
Slashdot's rate-of-post filter: Preventing you from posting too many great ideas at once.
Cruise control is all too often a safety hazard on the interstate. Safety requires space, the more the better, between vehicles. All to often cruise control is the reason cars remain in close proximity, mile after mile.
Oddly enough, there are virtually no traffic statistics that back up your claim.
There is some speculation that cruse control would lull drivers to sleep, but in fact this happens no more with CC than withoug.
As for slow passing, that's mostly a fallacy, because every cruise control allows driver over-ride, and passing a slower vehicle at one mph difference in
speed is not some how more dangerous than passing at 5 or 10 mph. The same driver that will allow the CC to take them slowly around another car would pass slowly if managing their speed manually.
Constant adjustment is part of the problem. People yoyo-ing up and down the highway are the real risk inducers.
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After reading this article (yes, I actually read the article and the deposition) I think automobile software should be reviewed by anybody that wants to review it. Let's face it, the software may be somewhat sophisticated, but it shouldn't be rocket science. Certain algorithms could even be patented for all I care, but the code quality must be reviewed. For those of you that haven't read the deposition from the link above, the upshot is that the expert witness saw horrible software practices being performed in a vacuum - as it were - he couldn't even take a pen and notepad in the room where he could view the software. He had to exit the room, make notes, then come back in after a security screening. This is the worst kind of software, and people are driving with it every day. Until software that has my life in its hands is peer/public reviewed, I'm going to buy only older cars for as long as I can. I sold my Prius after reading the above article.
On my recent model F150 there's a very handy feature: "Tow/Haul" mode. It changes the transmission shift behavior so that touching the brakes makes it downshift and STAY downshifted (and doing it again downshifts another step on the many-gear-ratios transmission), while touching the accelerator lets it shift back up. This is GREAT for long downgrades in mountains, even if you're NOT towing.
But it doesn't interact well with the cruise control. The speed control raises the throttle setting to keep you from going under the setpoint. But when you're over it just goes down to idle and lets your speed runaway. Touch the brakes to enable engine braking and the cruise control disengages. No automatic speed control for YOU on the downgrade. When the grade starts to level out the speed drops, and even before that you're back to watching the speedometer and doing manual adjustments,
Result: On mountain roads you're constantly disengaging and re-engaging the speed control.
They should integrate the two: When tow/haul mode is engaged, the speed control should send downshift signals to the transmission to control too-fast as well as too-slow conditions.
When tow-haul is on the speed control should signal the transmission to downshift when necessary, to keep the speed from running away and requiring the driver to brake. (The speed control's acceleration when too-slow will handle the upshift correctly.)
You'll still have to touch the brakes or tap-down the speed setting for curves and other locally slow zones. But then you'd just hit "resume" or tap-up the setting. Meanwhile the automation would handle the non-exceptional condition of preventing overspeed and runaway on downgrades.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
I just want a cruise control that doesn't go to 100% throttle when I want to resume 70MPH after slowing down.
Since I gave up hope, I feel much better.
As for slow passing, that's mostly a fallacy, because every cruise control allows driver over-ride, and passing a slower vehicle at one mph difference in speed is not some how more dangerous than passing at 5 or 10 mph.
Actually, it probably is a little more dangerous. People in too big a hurry* do get mad about this, and some of those people are mad enough/have poor enough impulse control that they'll take out their anger in unsafe manuevers (starting with tailgating and unreasonably close passing once it is clear, all the way up to actually attempting to run the slow-passer off the road).
The same driver that will allow the CC to take them slowly around another car would pass slowly if managing their speed manually.
That's mostly true -- while I imagine some drivers would pass faster if they were already controlling speed, but just don't care enough to move their foot back to the gas pedal if they're already on cruise, this is probably a far smaller effect than the one where many drivers would have their speed varying widely as they go up and down hills, also angering people and potentially endangering you by way of their response, so I think it does refute GP's argument that cruise control causes slow passing and thus is unsafe.
*If you're in a big enough hurry that waiting an additional 30 seconds to pass a vehicle is really enough problem to get mad about, you're in a big enough hurry to say "damn the law" and pass on the shoulder instead of sitting there stewing. Almost all the time, though, application of a little perspective will reveal you're not in that big a hurry.
Traffic would be less of a problem if more people learned how to use cruise control. It's an easy way to maintain a constant speed and increase fuel efficiency.
Or, you know, you could actually drive your car. I bet you have an automatic transmission, too.
Basic Cruise Control from the 60s and 70's could handle that situation. The problem is there are too many people who won't use cruise control
So true.
I have basic, stupid cruise control on my car and it rarely varies more than 5mph (+/- 2.5mph) on a grade when set at 65. But it seems like any time I drive for more than 30 minutes on an uncongested freeway it is inevitable that I'll run into at least one numbnut who isn't using cruise control and lets their speed vary by 10-15mph. They'll catch up to me, sit in my blind-spot until I put on the brakes and force them to pass. Once they are well ahead, I turn the cruise-control back on at my original speed and then I catch up to them, at which point they speed-match me again. If I gun it and get past them, as soon as I settle back at the set speed they start to catch up again. I can not figure out what the fuck is going through their heads, but it is super aggravating and it happens all the fucking time. Vast open stretches of freeway and these guys must be lonely because they won't leave me the fuck alone.
Nothing is going through their mind. Most of them haven't a clue about what is going on around them, they are probably yakking, and singing along to the radio, etc.
They recognize two situations, too far, and too close and that's about all. Their speed doesn’t even enter into their mind.
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In 1988 I knew an engineering student who swore that there were "advanced control algorithms" at work in the Dodge Caravan's cruise control - I told him he'd be lucky if there was anything more than a first order feedback loop: ( setpoint - speed ) * K = delta throttle, with maybe some limit stops.
As long as $0.89 analog computers could do the job, 1980s auto manufacturers had no inclination to turn anything over to microprocessor control. I think even after most of the engine fell under advanced microprocessor control, they still kept the KISS cruise control.
I think what is happening is that people can be paced easily. I see it when traffic starts to roll at a traffic light -- people will match the car beside them often.
>bad for fuel economy to let the cruise control slam on the gas to keep the speed up
that is/was true for cars with carburetors, fuel injected gasoline engines are going to be most efficient with least intake restriction at near peak torque engine speeds. (throttle pedal just varies intake restriction, less throttle more restriction, the ECU then determines fuel from the resulting air flow.) Automatic transmissions will get less efficient the higher the engine speed, and higher the torque, that could make it slightly worse efficiency to slam on the gas for a short period of time, instead of increased throttle for longer durations, but doubtful, or slightly. Of course at the same speed you will burn more fuel at more throttle, but if you were to go from 10% throttle to 80% throttle for 10 seconds to maintain your speed up the hill, then back to 10% versus going to 20% throttle for 30 seconds It will likely save total fuel to gas it for the shorter duration (definitely true in a manual transmission car.)
Much more dangerous is, by slow overtaking you're prolonging the time spent in the blind spot of the overtaken car, which is why for instance German law forbids overtaking with less than 20 km/h difference in velocity.
There is no such law.
The wording in the law (article 5 StVO) translates as "considerably faster". No numbers.
Maybe you should try a Dodge truck. My Charger downshifts without me doing anything if idle throttle results in not enough braking force down a grade. It always holds the speed to +/- 1mph. It also has adaptive cruise - the one option I appreciate the most, times 10. It really shines on a rainy night, when the guy in front hits his brakes enough to light the brake lights but not enough to slow his speed. It doesn't slow down unless he really does slow down, and without it I'd be tapping my brakes whenever I see his light up. And it's collision warning has saved me once from a fender bender, or maybe worse. I can't say enough about the software in my Charger; everything it does is just what I'd want it to do.
If I didn't have absolutely NOTHING to do, I wouldn't be here.