Physics is different here!
SL Physics is neither the Galilean/Newtonian “idealized” Physics nor a real world Physics virtualization and can be called hyper-real.
It allows surreal Physics simulations, in good accordance with Papert’s never-implemented proposal.
My questions, findings and conclusions will be posted here.
In a preceding post,
I showed a few examples a few examples of creating different types of objects each
one following different physical laws with TATI - The Amiable Textual
Interface for Second Life and its TATILogo programming language.
It must be noticed, however, that SL is a 3D environment where rotations around all axes are allowed. Therefore, besides LEFT and RIGHT rotations Logo commands, the analogous commands for the other axes, such as UP, DOWN, CLOCK, and ACLOCK were included in TATILogo.
In this example, I show these 3D rotation features. In the final part of the video, a sequence of commands allows for a simulation of a plane takeoff.
The commands were:
/33 create b1 geoobject plane orange
/33 forward b1 2
/33 right b1 90
/33 left b1 180
/33 right b1 90
/33 up b1 45
/33 down b1 90
/33 up b1 45
/33 clock b1 45
/33 aclock b1 90
/33 clock b1 45
/33 repeat 12 ( forward b1 1 ; up b1 5 ; forward b1 1 ; clock b1 5 ; right b1 5 ; forward b1 2 )
In the preceding post,
I showed a few examples of realization of circular trajectories with different kinds of objects each
one following different physical laws with TATI - The Amiable Textual
Interface for Second Life and its TATILogo programming language.
Example 1 - Newton's falling apple
In this example, I bring a Second Life version of Newton's falling apple.
The commands were:
/33 create m1 phyobject apple
/33 setpos m1 aboveme
Note: No, I didn't got inspiration for any new physical theory whatsoever.
Example 2 - 3D collision simulation
In this example, I show how TATI can be use to setup a simple virtual immersive 3D collision simulation in Second Life.
I simply had to type a few simple TATILogo commands in the chat window. TATI translates these TATILogo commands in Linden Scripting Language commands that will make Second Life rezz the two colliding bodies, position them, set the impulses that will put them in motion and invoke its Hawok physics engine to take care of all Physics involved.
Finally, I say 'go' and watch the simulation running.
TATI (The Amiable Textual Interface for Second Life) is able to
translate simple TATILogo instructions into Second Life commands that
will rezz different kinds of objects each one following different
physical laws.
The motivation is to help teachers interested in building simple
simulations for Physics teaching but would not go up the high learning
curve for Linden Scripting Language. TATI is able to translate simple
Logo-like TATILogo commands into different kinds of objects each one
following different physical laws.
In the preceding post, I showed a few examples of generating different kinds of objects each one following different physical laws with TATI - The Amiable Textual Interface for Second Life and its TATILogo programming language.
Here, inspired by the classic Logo example (Papert, 1980, p.58) of drawing a circumference
TO CIRCLE
REPEAT [FORWARD 1 RIGHT 1]
I show the realization of trajectories in the form of a circle with other TATI object types.
Example 1 - GEOOBJECT
In this first example, I ordered a GEOOBJECT object type, which is similar to a Papert's 'Geometry Turtle', with the shape of a plane.
Then I used the command REPEAT and geometric commands to make it do little steps forward and little turns to make a trajectory in the form of a circumference.
The commands were:
/33 create b4 geoobject plane
/33 repeat 36 ( forward b4 0.5 ; left b4 10 )
Example 2 - VELOBJECT
In this second example, I ordered a VELOBJECT object type, which is
similar to a Papert's 'Velocity Turtle', with the shape of a plane.
Then I used the command REPEAT and dynamical commands to make it to make a trajectory in the form of a square. Geometrical commands such as FORWARD and RIGHT are ineffective here. I had to use the 'velocity' commands SPEEDUP, SLOWDOWN, SPINUP, etc.
In this fourth example, I ordered a NEWOBJECT object type, which is
similar to a Papert's 'Newtonian Turtle', with the shape of a plane.
Then I used the command REPEAT and dynamical commands to make it to make a trajectory in the form of a square. Both geometrical commands and 'velocity' commands are ineffective here. I
had to use the APPIMPULSE command, to make it go forward
as well as to stop it and APPROTIMPULSE to make it turn and stop turning.
As Abelson explains,
“A dynamic turtle or dynaturtle behaves as though it were a rocket ship in outer space. To make it move you have to give it a kick by 'firing a rocket'. It then keeps moving in the same direction until you give it another kick. When you change its direction, it does not move in the new direction until you give it a new kick. Its new motion is a combination of the old motion and the motion caused by the new kick. (Abelson, 1982), p. 121).”
TATI (The Amiable Textual Interface for Second Life) is able to
translate simple TATILogo instructions into Second Life commands that
will rezz different kinds of objects each one following different
physical laws.
As I said before, the motivation is to help teachers interested in building
simple simulations for Physics teaching but would not go up the high
learning curve for Linden Scripting Language.
TATI is able to translate simple Logo-like TATILogo commands into
different kinds of objects each one following different physical laws.
References
Abelson, H., & DiSessa, A. A. (1981). Turtle Geometry: Computations as a Medium for Exploring Mathematics. Cambridge, MA: MIT Press.
