[thirdmainroad]

When two cars are parked in my house, I have to open the gates out to get the smaller car in.

Now I can reverse into the spot quite easily, but for the life of me, cannot go in nose first.

Are there situations where this is possible or are my driving skills not as good as everyone tells me they are? My reasoning is if I can reverse in, I should be able nose dive in!

[Rehaan]

Ever wonder why parallel parking is always done by reversing into the spot?

Ever seen how much more maneuverable a shopping cart is if you're pulling it towards you, rather than pushing it foward?

Ever wonder why fork-lifts maneuvering tight spaces in warehouses and picking up palettes with precision are rear-wheel steered (ie. effectively "driving in reverse)?


Simply put, the way the steering geometry works front-turning wheels offer way less maneuverability than rear-steering.


So then why aren't all cars rear-wheel-steering instead?

Because the trade off is stability and handling behaviour at higher speeds.

[thirdmainroad]

Originally Posted by Rehaan

Ever wonder why parallel parking is always done by reversing into the spot

Dang you’ve got it spot on. Thanks for the explanation! I sure can be dumb at times!!

[PreludeSH]

I think with reverse turning, the angular movement increases with the front pushed away around the rear wheels acting as pivot. Longer the distance between the rear and front wheels, the angular movement will be higher.

[androdev]

Car steering is based on Ackermann Steering geometry which allows different turning radii for different wheels thus avoids tire sliding.



The turning centre lies along the real axle which results in different types of swing/sweep when you steer forward vs steer reverse. Having a good understanding of the differences between fwd and reverse parallel parking will help you figure out other scenarios.



Say you are in Lane-1 and want to park the car in Lane-2. As you can see, steering in forward direction swings your front-right wheel all the way till the red line, it also requires the entire space in front of you to be free without any other cars and you will end up parking away from the kerb. During this manoeuvre, the car pivots around point C and then E. That's why you can do forward parallel parking only if you have acres of free space in the front.

On the other hand, steering it in reverse direction limits the swing of your front-right wheel till the purple line only, the space on the right can be occupied by another car (which can actually serve as a guide), and more importantly you are perfectly close to the kerb after the manoeuvre. During this manoeuvre, the car pivots around point C and then D.

In general, during forward steering, the front wheels move very far from the vehicle centre line while rear wheel barely move. This makes it manoeuvring in tight spaces very difficult with forward steering.

PS: Parking will become far more easy if you can make those gates swing all the way (180deg) to be flush with compound wall (shift the hinges to the outside). You can certainly do that for one shutter without interfering with your. neighbour.

Here is a cool info graphic (from ZF website) to extend our understanding to cars with rear wheel steering that is becoming common in high end cars:

[shankar.balan]

Originally Posted by androdev

Car steering is based on Ackermann Steering geometry which allows different turning radii for different wheels thus avoids tire sliding.D.

Originally Posted by PreludeSH

I think with reverse turning, the angular movement increases with the front pushed away around the rear wheels acting as pivot.

Originally Posted by Rehaan

Ever wonder why parallel parking is always done by reversing into the spot?

Simply put, the way the steering geometry works front-turning wheels offer way less maneuverability than rear-steering.

So then why aren't all cars rear-wheel-steering instead?

Because the trade off is stability and handling behaviour at higher speeds.

Fantastic series of explanations. Thanks very much indeed for the learning. It always has been instinctive and seemed logical to reverse into tight spots without analysing exactly why. These explanations and illustrations are superb, to help put things into scientific perspective.

[itwasntme]

Originally Posted by androdev

Car steering is based on Ackermann Steering geometry which allows different turning radii for different wheels thus avoids tire sliding.

PS: Parking will become far more easy if you can make those gates swing all the way (180deg) to be flush with compound wall (shift the hinges to the outside). You can certainly do that for one shutter without interfering with your. neighbour.

Excellent technical reply, thank you . Additionally, you can modify the existing gate itself into a folding one (with a strong set of hinges) so that the outer portion folds flush to the wall.

[venkyhere]

Even if not technically inclined, even if you don't "think" about this, instinctively, what strikes you easily - one end of my car has more freedom to move laterally than the other. So when moving into tight spaces, let me not restrict/trap the 'freedom end' into a tighter space than what the other end is enjoying. Because if I do that, I am not 'fully utilizing' the maneuverability possible outside the tight spot.

[MT_Hyderabad]

I can park nose first easily in this one. Come closer and parallel to the wall. Turn your steering fully. Move a little forward. Reverse a little with your steering straight. Turn your steering again and enter.

I do it daily in my parking.

[keroo1099]

180 deg hinges as Androdev has suggested or you can look at a sliding gate, ideally on the inside of your compound wall.

[aadya]

Simple reason is the fixed end of the car(nose) above the front wheels turn with a angular lag in relation to the turning wheel, whose movement is beyond our assessment. But the tail or rear end of the car turns with the same degree as the rear wheel(fixed), so it is easier the assess and guide the movement of the rear while parking.

[Revvman]

Originally Posted by Rehaan

Simply put, the way the steering geometry works front-turning wheels offer way less maneuverability than rear-steering.


So then why aren't all cars rear-wheel-steering instead?

Because the trade off is stability and handling behaviour at higher speeds.

Awesomely explained, Rehaan Nailed it!

Originally Posted by thirdmainroad

When two cars are parked in my house, I have to open the gates out to get the smaller car in.

While your main query is addressed, just noticed that in case you change your gates to be sliding ones instead of them opening out, you can get some more space for manoueverabilty and avoid any scratches on the cars on those off days or in case a less expert driver is behind the wheels.

[samyakmodi]

In a tight fit like this I wonder why would you want to park your car nose in ?

It is always better to park the car with the front forward because of a simple logic - when you are coming back home, you are not coming in for an emergency. But chances of you stepping out for an emergency are much higher - so the cars should always be parked facing outside.

either way - sliding doors in your use case scenario would always be much better and convenient. do consider.

[Guna]

Originally Posted by Rehaan

So then why aren't all cars rear-wheel-steering instead?

Because the trade off is stability and handling behaviour at higher speeds.

There is another issue with rear-wheel-steering. With the rear wheels steering, every time you want to tun left, the rear of the cars swings to the right, going out of the lane. This happens with our cars while reversing (nose going to the other side) and we tend to keep an eye of the front nose as well.

[Siddj38]

I always park with the nose in. Reason - People won't be able to 'sit' on the bonnet and cause a dent in.