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Ayneh
11-15-2009, 05:30 PM
Have you ever had a vehicle or another object that you wanted to travel at a certain speed but didn't know how to work it out? Maybe this thread can help!

This first thing we need to figure out is how tall Sackboy is. How tall Sackboy is will affect all our other calculations.

The smaller you decide Sackboy is the faster Sackboy will need to travel, because an object viewed from a smaller scale will need to traverse more space in order to match the speed of a object viewed at a larger scale.

Let's make Sackboy 150cm tall, so Sackboy matches real-world proportions and we have an easy number to work with. This means that when Sackboy is driving a car at 100mph, it'll look like 100mph as we recognise it.

To work out the speed of an object you'll need to make a track of a certain length, place your object at one end of it and then time how long it takes for your object to make it to the other end. You can use a stopwatch or the in-game race gates to time how long it takes.

If Sackboy is 150cm tall then a level is around 600m (1/3 of a mile) across.

A track 500m long will fit nicely in a level. To make a track this length first make a 4x4 block in small grid mode, make 10 of these and glue them together. You should now have a long rectangular object made of 10 blocks. This object is 15m long (1.5m x 10 = 15m).

You will need to repeat this 15m long object 33 times (15m x 33 = 495m), it might be easier to copy your 15m object 11 times and then copy that twice more to get to 33.

To make up the extra 5m missing from your 495m track make 3 more 4x4 blocks (1.5m x 3 = 4.5m), this will make an object approximately 5m long.

Now that you have a track that is 500m long all you need to do now is place your object at one end and time how long it takes to make it to the other.


35 sec = 50km/h = 30mph
18 sec = 100km/h = 60mph
11 sec = 160km/h = 100mph
1.5 sec = 1200km/h = 750mph (approx. speed of sound)

Using the above table if your object takes 35 seconds to make it to the end of the track then it was travelling at 50 kilometres per hour/30 miles per hour.

Rewind, adjust and repeat as many times as necessary until you get the time/speed you want.

The objects you make for Sackboy to travel in need to be to scale for the sensation of speed to be correct. All numbers in this post are rounded up or down to make them easier to work with.

ladylyn1
11-15-2009, 06:10 PM
Smart measurements, but I don't really think all that is necessary... Sackboy runs at "12" speed when you tweak a wheel to 12. On tanks for instance, if the wheel was going at 15 it might actually be going at ten. You could just race it and see how fats it's really going.


You can't race wheels without given dimensions.

The greater the radius the wheel has, the faster linear velocity it will gain for a given angular velocity (the speed number for a motor bolt).

Incinerator22
11-15-2009, 11:21 PM
Hmmm... I think you're right. I played a level called sack facts and it had a car chasing you that was exactly your speed and said that the maximum sackboy's running speed is 12.

thefrozenpenquin
11-21-2009, 07:16 AM
I just stumbled upon this, and had to hit some conversions.




Let's make Sackboy 4.921 ft tall, so Sackboy matches real-world proportions and we have an easy number to work with. Wait, I'm 6 ft tall (1.829m) no way would someone under 5 ft tall would drive 100mph, they couldn't see past the dashboard. Okay, sorry, back on the subject.

This means that when Sackboy is driving a car at 100mph, it'll look like 100mph as we recognise it.

To work out the speed of an object you'll need to make a track of a certain length, place your object at one end of it and then time how long it takes for your object to make it to the other end. You can use a stopwatch or the in-game race gates to time how long it takes.

If Sackboy is 4.921 ft tall then a level is around 0.3728 miles (1969 ft) across.

A track 1,640 ft long will fit nicely in a level. To make a track this length first make a 4x4 block in small grid mode, make 10 of these and glue them together. You should now have a long rectangular object made of 10 blocks. This object is 49.21 ft long (4.921 ft x 10 = 49.21 ft).

You will need to repeat this 49.21 ft long object 33 times (49.21 ft x 33 = 1623.93 ft), it might be easier to copy your 49.21 ft object 11 times and then copy that twice more to get to 33.

To make up the extra 16.4 ft missing from your 1623.93 ft track make 3 more 4x4 blocks (4.921 ft x 3 = 14.763 ft), this will make an object that is 16.4 ft long.

Now that you have a track that is 1638.693 ft long all you need to do now is place your object at one end and time how long it takes to make it to the other.


35 sec = 50km/h = roughly 31mph
18 sec = 100km/h = roughly 62mph
11 sec = 160km/h = roughly 99.5mph
1.5 sec = 1200km/h = 745.6mph (approx. speed of sound)

Using the above table if your object takes 35 seconds to make it to the end of the track then it was travelling at 50 kilometres per hour/30 miles per hour.

Rewind, adjust and repeat as many times as necessary until you get the time/speed you want.

The objects you make for Sackboy to travel in need to be to scale for the sensation of speed to be correct.

I messed that all up didn't I? I converted all the numbers and worked the math that didn't hurt my head. If anyone wants to know how fast they are going by the second then they can work it out.


Sackboy runs about:

14.1628 mph
22.7928 kmh
6.3313 meters/sec
1246.3290 feet/minute

srgt_poptart
12-08-2009, 03:57 AM
Sackboy runs at "12" speed when you tweak a wheel to 12.

Is that on a wheel of sackboys height? Cause speed changes due to size. It's why bikes with bigger wheels go faster. I made this one wheel that was ginourmous, and it was going more than twice sackboys speed set to only .4 speed.