Small object physics
by BigPapa · in Torque Game Engine · 04/05/2005 (8:49 pm) · 8 replies
Hello Gang,
I had posted this in the mathematics forum but got nothing so I deleted it and reposted here.
I've been scouring the forums for resources about physics for small objects. My main question is how to make objects behave like small objects.
For example, if you want the Orc model to behave like a toy soldier, and have it fall, bounce off a wall or floor and react like a small object instead of a human size object, how do you accomplish this?
Do you change the physics of the world so that objects in the world behave like small objects or do you change the physics of the object to accomplish the same?
The way I see it, it would be better to change the world physics so that all objects in the world are affected as opposed to having to change physics on all objects individually.
Please let me know if I'm on the right track.
Thx!
I had posted this in the mathematics forum but got nothing so I deleted it and reposted here.
I've been scouring the forums for resources about physics for small objects. My main question is how to make objects behave like small objects.
For example, if you want the Orc model to behave like a toy soldier, and have it fall, bounce off a wall or floor and react like a small object instead of a human size object, how do you accomplish this?
Do you change the physics of the world so that objects in the world behave like small objects or do you change the physics of the object to accomplish the same?
The way I see it, it would be better to change the world physics so that all objects in the world are affected as opposed to having to change physics on all objects individually.
Please let me know if I'm on the right track.
Thx!
#2
I scaled down the mass of the vehicle but forgot the scale down the spring force. That sent the car flying as soon as it hit the ground. Then scaled down the spring but then the springs where too weak and they could not hold the car so the bottom sit on the ground.
I've also experimented with the other parametes like drag, friction, restitution, etc. So far i have had mixed results.
I believe the main question i have is about the units of measure. I believe the mass is measured in kilograms. Is the force in newtons, kelvins, or what?
Perhaps if someone has more information about this or has already made a car behave like a toy car, i would apreciate some help. Thx
04/06/2005 (12:52 pm)
I tried it with the racing demo to make the car behave like a little toy car.I scaled down the mass of the vehicle but forgot the scale down the spring force. That sent the car flying as soon as it hit the ground. Then scaled down the spring but then the springs where too weak and they could not hold the car so the bottom sit on the ground.
I've also experimented with the other parametes like drag, friction, restitution, etc. So far i have had mixed results.
I believe the main question i have is about the units of measure. I believe the mass is measured in kilograms. Is the force in newtons, kelvins, or what?
Perhaps if someone has more information about this or has already made a car behave like a toy car, i would apreciate some help. Thx
#3
As far as units go, assume they're metric.
04/06/2005 (7:26 pm)
There was an RC racing game done in Torque that had pretty toylike physics.As far as units go, assume they're metric.
#4
This is the assumption I've been going on (Please correct me =)
04/07/2005 (6:53 pm)
I think the force is measured in Newtons, but I may be wrong.This is the assumption I've been going on (Please correct me =)
#5
04/08/2005 (3:39 am)
Pretty much everything is only "dimensionfull" insofar as it must have proper scale relative to the other units. We sort of loosely assume metric system in our coding but as long as the units work out in the end it really doesn't matter.
#6
I've been reading a lot of physics documents available on the net but i get lost after the three Newton laws of physics. I know that the answer is there somewhere among all the formulas but I just can't quite wrap my brain around it to the apply it in the game engine.
If someone out there can point me in the right direction I would really appreciate it. I don't expect nor do I want to be told exactly what to do. I want and need to learn.
Thx!
05/24/2005 (6:43 pm)
I'm really getting frustrated not being able to figure out the correct combination of vehicle parameters to get the behavior I'm looking for. I have pretty much experimented with increasing, decreasing values for the vehicle, wheel and springs.I've been reading a lot of physics documents available on the net but i get lost after the three Newton laws of physics. I know that the answer is there somewhere among all the formulas but I just can't quite wrap my brain around it to the apply it in the game engine.
If someone out there can point me in the right direction I would really appreciate it. I don't expect nor do I want to be told exactly what to do. I want and need to learn.
Thx!
#7
05/25/2005 (4:21 pm)
Can you describe in words (probably better to be descriptive as you can) the types of behaviour you want to see? Since there are so many parameters, it would be easier to answer something that was detailed then something less so, and someone that is pretty tight with the vehicle physics may be able to help you isolate what you need!
#8
06/13/2005 (5:24 am)
Just a quick update. I managed to get closer to the kind of behavior I'm looking for by changing the F32 sWheeledVehi9cleGravity from -20 to -45 in the wheeledvehicle.cc module. Now the vehicle bounces quicker that the one in the sample. Thanks for sticking with me guys. I know it won't be the last time :) 
Associate Kyle Carter