I use to own a 86 Jeep Cherokee with a hitch on the back. Standard height, wasn't jacked up or anything, but this guy wasn't paying attention to what he was doing and rear-ended me in his little nissan pickup. Did a job to his front end, but left me pristine. Moral? Get a hitch. ;-) llile@SALTONUSA.COM wrote: > Byron, > > I have fantasized about the car train idea myself. It is an obvious > extension of what we do now. > > I would hate to get hit by a train of 100 cars, though - a lot of kinetic > energy there! I would hate to be the lead car, too! I think there are > some serious barriers to such an idea. Assuming they were mechanically > linked, they would smack into something liek a semi! > > But if they were virtually linked - each car has a distance sensor and > maintains a constant distance to the next car, and a data link to the lead > car. If the lead car slams on the brakes or stops, each car can eat up > some stopping distance before whacking into the next domino. Presumably > there would also be increased energy absorbing capability in the cars > (5mph bumpers are a joke) > > The back of my truck is a good argument against 5mph bumpers. I've been > rear-ended several times. The bumper is welded up out of an 8" diameter > schedule 40 pipe, with a hitch welded up out of 3/4" steel plates. It is > rude, and crude. Makes kind of a big dent in the front of a car. Those > other kamakazes were sorry they had hit me, sorry indeed. My truck never > suffered at all. I need a bumper sticker that says "Warning: Stay back > 100 feet. I eat 5mph bumpers for Breakfast!" > > The real barrier to the car-train is not technological, but legal. If > anything ever went wrong, and 100 cars full of people died in a pile-up, > think of the liability! No company in their right mind would sell such a > product, even with many safety controls. > > Isn't there an AMTRACK line that you can load your personal car onto a > flatcar and ride in the passenger car? Not so sexy, but very practical. > > > -- Lawrence Lile > > > > > > Byron A Jeff > Sent by: pic microcontroller discussion list > 06/16/2004 10:10 AM > Please respond to pic microcontroller discussion list > > > To: PICLIST@MITVMA.MIT.EDU > cc: > Subject: Re: [OT]: Seatbelts - was: detecting emergency vehicles. Radar fools & Red > light cams > > > On Wed, Jun 16, 2004 at 06:49:13AM -0400, rixy04 wrote: > >>Reducing the maximum speed limit to 30 mph on all highways and 15 mph on > > all > >>side roads. This will reduce the auto deaths by 96%. ;-) > > > Imbalance the safety/security vs. convenience equation. > > >>>One thing I haven't seen covered in this discussion is the slippery > > slope > >>>argument. First it was airbags. Now it's seatbelts. Next? > > > Isn't next obvious? There is an easy and now technologically feasible was > to virtually eliminate auto accidents: don't let people drive. > > One concept, and there are folks out there working on it (no reference > handy > unfortunately) is building transit systems by linking cabs into long > trains. > The cabs drive themselves by whatever means (magalev, rail, etc) and the > linked > train can fly down the track at over 100 MPH. When you get towards the > destination, the train breaks down into its individual components (or > subtrains) that take you to your destination. > > BTW I came across this when reading up on Russell's Twike post. > > The effect is that a system that can regulate overall traffic flow can > function > far more effectively than a system consisting of "atoms" that act > independantly > of each other. Huge traffic flows can be generated without creating the > typical stalls that happen now. Consider this though experiment: heavy > traffic > is flowing smoothly down a single lane road at 40 MPH. One car slows by > hitting brakes because the driver needs to tell his children in the back > seat > to buckle up and play nicely together (an almost daily tast between me and > my > 6 YO). Now what happens? Every car in back of that car hits brakes in a > rolling wave. The virtual train slow tremondously, possibly even coming to > a > dead stop further back down the road. Now the original driver is finished > hiw slowing task and had clear road ahead and speeds back up to 40 MPH. > But > the damage is done, a traffic stall has been created that depending on the > heaviness of the flow, may never in fact dissapate. The transient stall > will > simply keep rolling backward towards the incoming traffic. Gosh Darn I > wish > those kids would have behaved! ;-) > > I'm fresh out of references this morning. I read that analysis on a > extremely > well put together website on one driver's observations of traffic flow. A > 2 minute search on Google didn't turn it up. > > Now back to the point. The failure point of the stall above is the fact > that > there is only tacit communication between cars. There's no signal from the > front car of the stall all the way to the back one that says "All Clear. > We're all going to accelerate to 40 MPH on my mark... 3, 2, 1 , MARK!". No > driver in his right mind is going to trust that Grandma or the teenager in > front of him is going to follow the directive to the letter. > Miscommunication > and failure to meet expectations of others are why we have accidents. > > So the the linked cab concept can have those communications mechanisms and > since the system is driving all of the cabs, there is a reasonable > expectation > that a "Accelerate to 150 MPH on my mark..." will be followed to the > letter. > > Just think about a freight train on the tracks. Now imagine that same > train > with each car with its own engine and driver and they were not coupled > together. Would you want to be hurtling down the track at 80-90 MPH in > such a > situation? That's the typical expressway. It's really amazing that we > don't > have more accidents and deaths out there than we do. > > BTW most of these site are touting the concept on the impersonal car. But > in fact a mix of both personal and impersonal cars could work. A scenario > such as a long trip or commuting the work would occur in your personal > cab with your stuff in it. However a quick bite, or a crosstown meeting > you can afford to just hop the first available. There may even be a system > where you can lock up your stuff in your cab an rent it out to others > during the day when you're not using it (with appropriate video and ID > monitoring of course). > > the 30 MPH on the highway doesn't work not because of the safety issue but > due to the inconvenience. I've often thought on long car trips "Why in the > hell do I have to drive!" thinking all along about a multimodal > infrastructure > that have the car drive itself: optical, map, GPS, radio beacon, obsticle > avoidance. > > Just some thoughts. > > BAJ > > -- > http://www.piclist.com hint: The list server can filter out subtopics > (like ads or off topics) for you. See http://www.piclist.com/#topics > > > > -- > http://www.piclist.com hint: The list server can filter out subtopics > (like ads or off topics) for you. See http://www.piclist.com/#topics -- http://www.piclist.com hint: The list server can filter out subtopics (like ads or off topics) for you. See http://www.piclist.com/#topics