Hello!

Chain Links.skp

I've created a model with three examples, every link is created with many sub-groups to get the "hole" that you find in chains.
It's probably easier to download the model and look inside each link and see what I mean.

/hpisse

I think its better for the Physics Simulation to make the model bigger.
Cause one "hinge" joint is about 8,28" or 21,04cm in diameter, so its fairly small from the beginning.
And its easier to do the model bigger from beginning than scale down all joints.
That is what I think.
/hpnisse

Does it help to reinstall SketchyPhysics?
http://sketchyphysics2.googlecode.com/files/SetupSketchyPhysics3x-Jun27.exe: download-link.

Or just replace the ClassExtentions.rb file:
ClassExtensions.rb

in the folder: C:\Program Files\Google\Google SketchUp 7\Plugins\SketchyPhysics3 (I have Win7).

Hope you get it to work!

Hello!

I think I figured out the problems with your model.

Its hard to explain so just download the file, and so by yourself.

folding shutter.skp

The one to left is open by pressing the "W" key.
And the one to right is open by the hand tool in the Simulation.

/hpnisse

Hello!
There is two ways to get it work with keyboard.

Simple:
When you start the simulation there popup a window "SkechyPhysics Control Panel".
Click on that so its active, then the keys will work.

Less simple:
Change the shortcuts to the tools.
Click on: "Window" - "Preferences" - then "Shortcuts".
Then change the shortcuts to whatever you want (or just delete them), tip!, add "ctrl" or/and "shift" key to the letter, then there is the same letter but you need to press "Ctrl" or "Shift" down at the same time.

Just type in the tool-name ;that you want to change shortcut to; in the "Filter" box.
Ex. of standard shortcuts:
Q - Rotate
E - Erase
R - Rectangle
A - Arc
S - Scale
L - Line
C - Circle

Hope this work (I know it do )
And have fun with SP.
/hpnisse

It should be in ruby I think.
http://sketchyphysics.wikia.com/wiki/Ruby
It says that Ruby is used to control SketchupPhysics so I think SP would be written in that script.

Good that your happy.
Have a nice summer!

You use servo as motor, I changed it so all servo is the "motor" joint insted. and it work perfect.
Then I use my script and changed some stuffs so it would be easy to change the speed.
Samochód.skp

To change the speed of the wheels then change the number "3" in the "Speed" box.

if frame==1
setVar("speed",3)
end

then it will work fine.

/hpnisse

I've got both work correct both forward and backwards.

Download and look this model.
hpnisse vs hobbnob.skp

I don't know what you did but here I got both working with the up/down arrowkeys at same time.

Hope this helps understanding!
/hpnisse

Somewhere in the model, just create a static box or something and put this (and the steering script) in the "ontick" field!

Then it will work

Hello!

if key("Up")==1
  setVar("drive",1)
elsif key("Down")==1
  setVar("drive",-1)
else
  setVar("drive",0)
end

Put this code somewhere in the model, and on the motors (that will let the car go forward/backwards), put this in controller field:

getVar("drive")

This should let you control the car with up/down arrows. (when you don't push either up/down the motors will stops)
And if you want to steer your car you can use the same code with some changes.

if key("Left")==1
  setVar("steer",1)
elsif key("Right")==1
  setVar("steer",-1)
else
  setVar("steer",0)
end

And in the servo joints, there shall be only one of the field "Max"/"Min" with numbers (degree of rotation of the wheels), and the other of these two fields will be empty (set to zero "0").
And the controller field in the servo will have

getVar("steer")

hope this helps!

/hpnisse

There is a link on this page that says "SP for Mac".
http://sketchyphysics.wikia.com/wiki/SketchyPhysicsWiki

Direct link!
http://sketchyphysics2.googlecode.com/files/SketchyPhysics3RC1-MacAndWin-Fixed.zip

It´s a .zip file and probably to extract the file in the Plugin folder that previous Reply says by "dale".

In this page you find a link and very much help about SketchyPhysics!
http://sketchyphysics.wikia.com/wiki/SketchyPhysicsWiki

This is direct link to download the SP3RC1 in Windows .exe file. (link to Mac is on the other link above.
http://sketchyphysics2.googlecode.com/files/SketchyPhysics3RC1-WinInstaller.exe

Do the motors have controlleble functions.
When you open the UI and select a jonit (motor), it should be in the controller field: slider('NAME'). (left picture)
!AND the joint need too be connected to something to show the slider.!

Then there will pop-up a "slider" in the blue controllpanel when you start simulation. (right picture)

/hpnisse

Put

if key("W")==1; oscillator(50);else;0;end

in the controller box.

Change the key and oscillator speed by change the "W" to something else ("Space","Shift" etc) and (50) to whatever you want.

/hpnisse

edit:

if you put

if key("W")==1;oscillator((slider("Oscillator")+1)*20);else;0;end

in controller box you will get a slider to adjust the speed of the oscillator when you have press the key.

/edit

It would be helpfull with a upload of your model.
It´s very easy, just post a new reply and click on "upload attachment" below the writing window.

Then it would be very easy to understand your problem.

/hpnisse