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What reason did the Uber car have for going 38 in a 35 zone?
Surely the speed limit was lowered from 45 to 35 for a reason, probably for safety reasons.
Can the car not read road signs? It doesn't have the excuse of "I was watching the road, not my speedo" for a minor speeding offence. Did Uber fail to update the map data when the speed limits changed?

The risk of death being hit by a car below 30mph is relatively low. It increases rapidly as speed increases.
9% chance of death at 30mph.
50% chance of death at 40mph.
Starts reaching 100% fatal over 50mph.

There's a reasonable chance the woman, who may well have been in the wrong, would still be alive if the car was traveling at or below the 35mph limit.

source: https://nacto.org/docs/usdg/re...

There's another study that showed a reduction in speed by 5km/h would result in 30% fewer deaths. That happens to be how much the Uber car was over the limit.
http://humantransport.org/side...

Does it result in fewer accidents? If drivers are slowing down because they sense that the conditions are less safe, then the absence of lines is just delaying people for no benefit.

Except of course for the benefit of increasing the survivability of collisions.

At 20 MPH, 5% of pedestrians involved in a car-pedestrian collision will die.

At 30 MPH, it is 37-45%.

At 40 MPH it is 83-85%.

If you are thinking of traffic as simple car vs car, then speed limit should be one thing--probably a lot higher than they are now. Because people in cars are pretty impervious to injury.

But as soon as you realize that **this street is going through a neighborhood** everything changes. Honestly we should not allow cars (or anything else) to go faster than 15-20 MPH in neighborhoods and places where there are many people.

Fast driving drives away people and endangers them. That is the opposite of what we want in our communities.

The most effective strategy for eliminating traffic fatalities has relied heavily on this approach--reduce speed, and fatalities reduce at least proportionately.

Sources:

http://www.visionzeroinitiativ...

http://humantransport.org/side...

1/3 of drivers speed by over 10 MPH:

  http://well.blogs.nytimes.com/...

Risk of death DOUBLES for that increase between 30-40 MPH, and goes up by a factor of 9 from 20-30 MPH:

http://humantransport.org/side...

It's not just technically correct, it's actually correct. You're basically blaming murder victims for getting murdered here - "shouldn't be out at night" type of bullshit. No. It's the driver's fault almost all the time and it's the attitudes of drivers that must be changed.

It's this kind of idiotic mindset which causes so many accidents each year. Residential roads are 30 for a reason; http://humantransport.org/sidewalks/SpeedKills.htm

And people who don't want to kill pedestrians or cyclists. If you hit a pedestrian at 5 mph, there is a 5% chance of death. If you hit a pedestrian at 40 mph, there is an 85% chance of death.

Considering that cities are trying to become more cyclist friendly, perhaps we need to think about trying not to kill them. You may feel like a big man driving 35 mph in a 25 mph zone, but if you only have a split second to slow down 5 mph in each case, the death rate is ten times higher than driving the speed limit.

You do understand that in a pedestrian zone speeding "just a little" is a huge increase in risk. It's a completely different animal from speeding on a highway. The source Google just found for me quotes two studies, and the lower estimate is 5% fatality rate at 20mph, 37% fatality rate at 30mph. If it were linear in speed, 22mph would have a fatality rate of 11.4% -- over double. There's a quadratic component -- 40mph rate is 83% -- but it's not that large, and estimating double risk at 22mph is reasonable. So in a place where pedestrians might be, especially low-mass pedestrians, it's appropriate to declare that the speed limit is 20mph, period.

And how many miles of school zone do you drive through per day? 15mph, vs 20mph, is a minute per mile. I just eyeballed some of the local elementary school zones on Google Maps, and none of them is more than 1000 feet long. That's 12 seconds.

If you can invent a detector that works for both cars and bikes, yet still has the lifespan and approximate cost of the current detectors, go suggest it to the appropriate folks.

I managed to get one misbehaving intersection's sensitivity increased by calling 311 and reporting it. But the crack at the other, at the intersection of a low-traffic street and a major traffic artery, appears to be too long for such a quick fix. The long-term solution is to replace ring-shaped detectors with quadrupole detectors. This figure 8 shape concentrates the sensitivity in the middle of the lane, allowing traffic engineers to crank up the detector's sensitivity while still rejecting spurious signals from large vehicles in adjacent lanes. The only drawback in retrofitting existing intersections to use is that recutting the asphalt costs more than zero. I just wish I knew more about the economics traffic engineering and how to organize other area cyclists so that I could submit a proposal to the city.

Either petition to change the laws

Any such petition would get buried by the incumbent media, as the Eric Eldred Public Domain Enhancement Act petition from the early days of Creative Commons did.

or live with them and go make more noise with your free fictional entertainment.

Once I've created a work, how do I check it before I publish it to make sure I haven't accidentally plagiarized something non-free? And in the case of a medium with gatekeeper companies with imprimatur power (e.g. video games, which are controlled by Sony, Microsoft, and Nintendo), how do I get a work past these gatekeepers?

You're right to ask, because in a purely mathematical sense it is limited. A vehicle on pedestrian accident at 100mph will cause 100% fatalities. AT 200 mph it's still 100%.

But at lower, more common speeds, you'll see it's exponential, not linear or flat.

http://humantransport.org/sidewalks/SpeedKills.htm

There's a web page that explains it in gory, but still somewhat EE-oriented, detail: http://humantransport.org/bicycledriving/library/signals/detection.htm

What you need to imagine is that there is a big stream of something flowing out of the top of the loop, around, and back in the bottom. Position your bicycle so that you put a closed conducting arc around the largest possible amount of that flow. For example, position a wheel on a wire, in the plane of the wire or tilted inwards towards the middle of the loop. That puts your wheel perpendicular to the "flow", and thus you cut a large part of the flow, and the detector will sense you.

Note that if you position your bike perfectly vertically in the dead center of the detector, you will intersect little or none of this "flow", and hence you will not be detected. If you lay your bike down flat on the pavement, you will detect a lot.

Some detectors have a figure eight configuration (two side-by-side rectangles, usually) and for those, the flow is directed from one rectangle into the other (over the line separating them). So for those, it is GOOD to be dead center and perfectly vertical, you will intersect a lot of the flow.

And electrically speaking, that "flow" is the alternating magnetic field caused by a current in the detector. Anything conducting that intersects the field, forms a transformer, and that is electrically different from not-a-transformer, and that is what the detector actually detects. It has to be a changing field; a constant, DC field (like a magnet) has no effect. If you knew the frequency of the detector (10-200 KHz, says the article) and moved the magnet back and forth across that wire that fast (10,000x per second) then the magnet would work.

See also: http://www.coolmagnetman.com/magpipes.htm -- a falling magnet is also a changing magnetic field.

Segway stopping distances are comparable to a bicycle.

just because something doesn't go 100 mph, doesn't mean it should not be allowed on -public- roads, freeways are obviously different, NEVs are not meant for those, read what NEV stands for.

http://www.humantransport.org/universalaccess/page 2.html Principles of Universal Access

1. Universal Access to Destinations
All destinations served by the public road system shall be accessible by pedestrians and by drivers of all vehicles (including bicycles), except that vehicle operation may be restricted for reasons of excessive weight, noise or size, or extraordinary potential for damage to the property or person of others.

2. Equal Rights of Use
People's right to use that portion of a street designed for travel is not diminished by less weight, less size, or less average speed associated with their travel mode. The adequate accommodation of heavier, larger, faster travel modes by a road's design must not imply its inadequacy for or unintended use by smaller, lighter, or slower modes. Demand-actuated traffic signals must detect and serve a diversity of users including bicycle operators in the roadway and pedestrians using crosswalks.

3. Integration of Modes
Travel by different modes shall not be segregated by law or facility design without compelling, objective, scientifically valid evidence of operational advantages of segregation that outweigh the disadvantages. Segregation of pedestrian from vehicle traffic may be warranted on busy roads due to the different maneuverability and nighttime visibility characteristics of pedestrians and vehicles. Segregation of different vehicle types is undesirable, as this segregation almost always creates increased conflicts at junctions, forces users of some vehicle types to use inferior facilities, or stigmatizes users who violate the segregation policy for safety reasons.

4. Uniformity and Simplicity
Transportation systems should be simple and intuitive. Designs and regulations should be uniform across facilities. Similar traffic situations should be treated in a similar manner, enabling more rapid and reliable user behavior. Vehicle-type-specific exceptions to the Rules of the Road are undesirable because such exceptions make traffic movements less predictable and traffic negotiation less reliable.

5. Accessible Surfaces
To the extent practicable, travel surfaces should accommodate travel on foot with minimal trip hazards and via common assistive devices such as wheelchairs. Roadway surfaces should be as clear as possible of hazards for narrow tires such as bicycle wheels.

6. Crossable Roadways
Crossing distances at non-signalized access locations must not exceed the distance that can be covered at walking speed before traffic may arrive from beyond sight distance, or during reasonable gaps in roadway traffic. Refuges provided to reduce crossing distances should be large enough to store assistive devices such as wheelchairs and strollers. Traffic signal timing should provide adequate clearance intervals for safe crossing by pedestrians and slow vehicles.

7. Appropriate Space for Use
Adequate space for maneuvering and recovery should be incorporated for all vehicle operators and for pedestrians including wheelchair users. If it is desirable to accommodate faster speeds for some modes while slower modes are present on the same road, the road may be designed to facilitate easier overtaking between modes. Overtaking activities should take place at distances appropriate for the difference in speed, maneuverability of modes, and vulnerability of users.