Kinematics of Reverse Angle Parking
observablehq.com
observablehq.com
It's used in areas where you might have roadside parking along a road, either parallel or angled. It has higher linear density than parallel and is easier/faster. Compared to forward angled parking it removes the "backing out into traffic you can't see because your rear pillars and the hausfrauenpanzer next to you have completely blocked view of the oncoming traffic" (so you go slow and figure any drivers coming down the road don't want to die today either). You safe the road by stopping to park, and have road visibility as you back in. Coming out you get better visibility because your upstream neighbors corner is further from the traffic and your eyeballs are also closer. An added bonus is that bicyclists have very little reason to ride in the zone of opening doors, compared to parallel parking.
Some places it is popular. Changing to it from forward angled makes people crabby.
At first I wondered if the road can be slightly narrower while still allowing one to get into the parking space, but if you look in the OP article at how the orange envelope is shaped by the way the front end swings around, I don't really think that's the case.
In general, I'm confused about why angle parking is picked over perpendicular parking. It's significantly less linear density (reduced by the factor cos(theta)), but the square shape of cars means the road width occupied by the parking is hardly less. (The wasted space is the triangular patches between the parked cars and the road/sidewalk.) Parallel parking has even lower linear density, of course, but takes half the road width.
Upvoted just for this one word!
Just like Hausfrauenpanzer, with bonus alliteration!
OK - well, this is of course not quite true, because the car is moving, and so it's not quite rotating around a fixed point. But it's close enough that you can pretty much start your reverse parking manoeuvre by putting one wheel in the right place, so its contact point is lined up with wherever it ultimately needs to be - but it doesn't really matter which angle, provided it's within 45° or so. Then turn full lock in that direction (left for left wheel, right for right wheel), on the spot, and slowly reverse until the other wheel is lined up too.
Now you're done. Straighten the front wheels and go in backwards.
It's handy to bear in mind the swept volume, as there will be some overhang, but when going in backwards with this technique you don't typically have to worry about it too much.
(Making the wheels turn on the spot is not the best thing, but you can fix this once you're confident with the basic manouevre.)
Contrast this with drivers I've seen who will haul ass into a parking space at 15 MPH and then brake immediately.
EDIT: To be clear, I'm describing a perpendicular-parking scenario, where people usually make a right angle turn going forward to occupy the space.
The problem in my case is that the road is so narrow that it's very easy to hit the barrier on the right when reversing while turning to the left — that was what prompted me to make the visualiation.
I park in a standard parking garage, with forward angle parking and one way traffic flow. I occasionally encounter vehicles reverse parked, which confuses me, but whatever, but then also encounter vehicles driving backwards (well, forward facing, going against the posted signage) through the parking garage. This is always a big headache, because again, this is a one way parking garage, and for some reason THEY never seem to think they should back up or get out of the way of the person driving the correct way through the garage, so I always have to do some extra maneuvering and wait for them to pass, and I usually only have a small margin before the train arrives, and--
Assuming they are not simply idiots who can't follow the signs, my next assumption would be that these are the people who are reverse-parking, looking for a spot to back into.
Anyway, if you have difficulty making the turning radius to pull straight into a forward angle parking spot, there is a very simple trick: make a three point turn, attempting to pull into the spot to the right of the empty spot, then when you are almost to the bumper of the parked car, back up and straighten out, which puts you at the perfect angle to drive straight into the angled spot now in front of you.
It beats the pants out of getting halfway into the spot before realizing you're about to hit the car on one side or the other and trying to straighten out after the fact.
It bothers me when people decide to ignore the marked direction of traffic flow in a garage or parking structure to facilitate their preferred parking style; if there were a reverse-angle parking garage I used where people went backwards through but to forward park I'd be just as annoyed.
I drive a large Ram pickup truck and backing in is pretty much the only way that I can park it accurately.
Also, as a beginner, it's very hard to "feel" how much you're supposed to turn with variable rate — I guess this only comes with a ton of practice. In the driving school, the way we were taught all the parking maneuvers is to reverse straight until you catch some reference point, then immediately turn to the max for the sharpest turn.
This may or may not be a legal traffic maneuver where you live and obviously can only be performed with both lanes clear.
Also, for OP: You'll often find that getting into a spot is difficult, but getting out again is trivial. Obviously you could try to just reverse the "leaving movement" as part of your parking maneuver. This can help with finding the perfect spot for starting the parking maneuver.
Having said that, it would be nice to see this adapted to parallel parking since that is a much more common parking scenario.
I made the viz for my real-world situation — reverse angle parking is quite common where I live (Ukraine), and it's the type where we got our parking spot (took a long time since all the spots around my apartment complex are sold out). https://en.wikipedia.org/wiki/Back-in_angle_parking
But it was concerning trucks and how adding additional axes and especially adding even one trailer joint (but especially two) made solving this conventionally impossible.
With some funky transformations into other number-spaces there were some analytic solutions for it though.
[1] https://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=7463491
[2] http://www.tsi.lv/sites/default/files/editor/science/Researc...
Presumably there's a spot like this on every car; you just have to figure out where it is.
The rear seats themselves are mostly decorative unless you have very short friends/family. It's not a good car for four people. But for one or two, it's amazing.
Driving exams involve performing a 2-point reverse turn with the rear inside wheel not going further away than 1 meter from the kerb, no more than two stops (except for traffic/safety related reasons), no more than one engine stall, no forward movement and no contact with the kerb itself.
Which curb? I'm mostly parking in lots with perpendicular parking on both sides of the lane. The only curb involved is the one at the back of the space I'm backing into (unless there's a pull-through from the other side, then not even that).
https://www.google.com/maps/@37.4110349,-122.1605769,294m/da...
I assume you mean gap, but when you start reversing and are not aligned with your parking spot yet, the thing you'll soon see in the rear mirror is the car parked in the next slot. No gap.
Idk about other people but I feel like I've got very bad depth vision in general, and telling how far my car's rear is from a wall or another car when looking through the mirror is very difficult.
Regarding how far back to go, I find that it's the same problem as parking forward. You just need to figure out how to judge some reference point on your car with whatever is around you. I agree that's one of the trickier things to figure out.
Forward parking sure has the same issue but for me at least it's much easier to assess depth right in front of me than 2-3 meters behind, through a little mirror. And I mean I can park in front of a wall and leave a 15-20 cm gap between the bumper and wall without much trouble, but it is seriously difficult for me to say whether there's half a meter or one and a half between my rear and the next object. I guess they invented reverse cameras for a reason, I just haven't bought one.