# The ability to push cars

Buddy ran out of gas while driving a basic car, he was headed to another car to siphon it only 10 blocks away. No gas can so he couldn’t siphon some and then bring it the few steps back. So I suggested he try and push it, told him to grab the car and push, no luck he didn’t have enough strength.

But we have all been in this situation before and unless you have to push up hill or you have a large vehicle, one guy can usually push a car.

Yeah that system is weird.

Probably just a problem with the math. I’m guessing it doesn’t take into account that a heavy item on wheels doesn’t act like it has the weight it does.

The math is weird. Cars do take wheels into account.

To balance it, I’d need someone to list a bunch of cars that should be pushable and some limits - cars that shouldn’t be pushable.

Suv’s and bigger need more than one person to push. Pickup trucks, cars, beetles, sports cars, solar car, electric car and similar are all light weight vehicles that some one should be able to push with average strength. I can’t remember all the cars in game but I think that accounts for most.

http://www.plantengineering.com/single-article/calculating-proper-rolling-resistance-a-safer-move-for-material-handling/82fa156f91ea516c6b08be3bc595db65.html

has a great calculation system for determining what it would take to move an object based on weight of object, wheel type, and wheel size.

In any case it shouldn’t be a simple ‘yes’ / ‘no’ on if you should push something. I know that with enough strength you were able to drag vehicles, the issue is in balancing what an average person -could- move and dialing down the values based on that. If you’re Magnus ver Magnusson no reason you can’t haul a city bus a couple of blocks.

If the vehicle is in NEUTRAL (controls not broken, have the keys or have it hotwired), the tires and such are all in very good shape, and the road is very smooth and flat, an average man could move a bus. The problem is that, in a post-apocalype like we’re talking about, and in a simulation that assumes all ground is “flat enough”, some of those kinds of things are going to have to be arbitrarily decided. Even a slight upward incline radically alters how much weight can be moved.

anyway,. after looking at the data, if you want to have the least variables possible you would need to consider all proper cars as being at least 1/3rd the weight since the coefficient of friction of ordinary tires on SAND is 0.3 (the number gets better with better road material, but lets just go with worst case). next you take an average of the radius of the all the tires and divide the weight again by that number. so if it has 4 20-inch wheels, that is 10 inch radius meaning divide the weight by 10. for a 3000lbs car step one 1/3rd it = 1000, step 2, 20 inch wheels = 1/10th = 100 lbs. and then x2 for “getting it moving” = 200lbs. so if you can push 200 lbs you can move a 3000 lbs car.

on the high end a regular tire on a proper surface like concrete gives us a coefficient of 0.01, which would result in something being considered only 1/100th the weight for the purposes of pushing it, before accounting for wheel size. which can let a regular person push something like 10000 lbs easily.

The game doesnt assume everything is completely flat though. Ive lost vehicles because it was over shallow water and i couldnt push it, but if i debugged it out of water, i could push it just fine.

what about pulling car or trailer by wire steel ropes?
after that can be car what can pull the trailer… Jeeses how i wish to drive a haul pulling trailer - it’s will be lot of fun.

[quote=“vivat, post:11, topic:14078”]what about pulling car or trailer by wire steel ropes?
after that can be car what can pull the trailer… Jeeses how i wish to drive a haul pulling trailer - it’s will be lot of fun.[/quote]
Also useful for pulling annoying cars out of the way on bridges.

hell, yes!