help.doc

一个由c转成java的3D robot 仿真平台

INFORMATIONS TO ROBOSIM

This program has been generated for a software practical course by Johannes 
Sch黷zner,under the direction of Dr.Thomas Br鋟nl, University of Stuttgart, 
in 1996. It is based on the 'Studienarbeit' by Rainer Pollak, made in 1992 
and programmed in C. 

->Introduction 

RoboSim is a program which simulates a six-link robot. You can control the 
robot in several ways and manipulate it, for example giving the links new 
lengths or changing the weights belonging to the indicated angles. It's also 
possible to make the robot save pre-allocated positions and to teach the robot
a sequence of movements.Also, this software can be used to control a real 
robot. This robot is a Lynxmotion manipulator, available from Joker Robotics. 
In the following passage the possible commands are explained in more detail. 


->Useful Advice

This Java applet needs a reserved place of 920x670 pixels. Otherwise parts of 
the drawing are hidden by the panel on the right side. If you can't see a ro-
bot between the control panels, it's useful to click several times between the
panels. If the robot seems to stop while doing a move and the scrollbar labels
disappear, it might be helpful to move the mouse across the robot. 



->Restrictions 

Since there exist a lot of security restrictions, the loading and producing of
control programs can only be done with the Java interpreter. Unfortunately, 
applets started with Netscape are not allowed to do this. 
The real robot can only be controlled by a special RoboSim version, because 
its control needs C-code which has to be integrated into this Java program. 
This integration would make it impossible for this program to run on every
computer system. So the integration has been realized only on a limited 
version. 



->The Commands 

Forward Kinematics: 
This command is used to control the robot and its rotation links direct-
ly by modifying the angles corresponding to these links. The angles' values 
are restricted to sensible ranges which are shown above the scollbars. They 
are as follows: 
              Angle 1: 180.0 degree to -180.0 degree 
              Angle 2: 30.0 degree to -210.0 degree 
              Angle 3: 30.0 degree to -210.0 degree 
              Angle 4: 180.0 degree to -180.0 degree 
              Angle 5: 90.0 degree to -90.0 degree 
              Angle 6: 180.0 degree to -180.0 degree 
The real robot has not got the facilities of angles 4 and 6, so these angles 
are not available to the user. 

Inverse Kinematics: 
You can control the robot by giving it a target position (x-, y-, and z-value)
with this command. The movement is executed after a click on the execute, bu-
tton just below the scrollbars of the inverse kinematics. If a target point is un-
reachable, the robot stops. By pushing on the other button in the auto control 
area, you can select, whether the robot should move in a straight line or on an 
arbitrary trajectory.

Determination of the arm lengths: 
This command allows you to vary the length of the arms of the robot. Also 
there exists a test for collision. If a collision is detected, the change of the 
arm lengths is not executed. The execution is only performed, if the corresponding
execute button is pushed. The possible new lengths are limited to sensible ranges 
shown above each scrollbar. They are as follows: 
              Arm 1: 15.0 to 4.5 
              Arm 2: 15.0 to 2.5 
              Arm 3: 15.0 to 2.5 
If the real robot is controlled, this command can't be selected, because the 
real robot has fixed arm lengths. 

Angle weights: 
Again, the values given to the text fields are only accepted after pushing 
the execute button. Then you have new angle weights. They are needed to obtain the
best solution of the inverse kinematics. The values have to be positve integers. 

Point of view: 
You can change the point of view by dragging the robot with the mouse in any 
direction. By using the zoom scrollbar, you are able to increase and decrease the 
size of the robot. 

Speed: 
You can select your required speed with the corresponding scrollbar. By 
switching off the double buffering mode, the robot motion is much faster. 

Define/Go to positions: 
Three positions can be defined simply by pushing the define pos button of your
choice. By doing this, the six actual angles of the robot and the actual open/
close state of the hand are saved. This position can be restored by pushing the 
equivalent go to button. The first button (Go to Init ) holds the angles of the 
robot at the beginning. If you want to see an example movement, push the example 
button. 

Virtual/Real robot: 
You can choose between the virtual robot as shown in the middle of your screen
and a real robot (Lynxmotion manipulator). Selecting the real robot, the arm 
lengths and the angles four and six can't be changed, since the real one consists 
of only four links. 

Open File: 
By selecting this button, you can load a file which either has been written 
"by hand" or has been produced with the Teach button. How to write executable 
files and use the Teach button, see the following links. 

Teach: 
After having activated this button, a file dialog window appears in which you 
can choose the name and the directory of the file which will be produced and 
written automatically. By doing this, the Teach button will be replaced by the
Enter button and the Stop button will be enabled. Now you can control the ro-
bot as usual, but every time you push the Enter button, the actual robot 
angles and the actual open/close state of the hand are written into the indicated file. 
This mode is only stopped, if the Stop button is pushed. At the beginning of 
this mode, the actual linklengths, 
speed, and zooming factor are stored. 

Writing own control programs: 
You can write control programs such like these ones being produced by the Teach
button, but you have got more command power. Every command starts with a com-
mand character and is completed by the arguments needed for this command. 
Every input, e.g. command character and arguments, must be in a seperate line.
Otherwise the required motion of RoboSim cannot be guaranteed. The possible 
commands are: 
"f" This character stands for forward kinematics. It has to be followed by six 
numbers in double format representing the new angles. Remember that every command 
and every number has to be in a row of its own. 
"i" indicates inverse kinematics. In the next three lines there must be the three 
coordinates of the target point. 
"l" By choosing this character, which represents linklengths, you can deter-
mine new lengths for the links. These lengths has to be in the allowed ranges. 
"w" is the abbreviated form for angle weights . The arguments of this command 
are the six new angle weightswich are integers. 
"s" represents speed. It has only one argument - the new speed. The range of 
possible values starts at 1 (slow) and goes up to 82 (fast). 
"h" signifies that the content of the following line should be regarded as the
open/close state of the robot's hand. 0.0 means a fully open hand and 1.0 a 
totally closed one. 
"z" indicates the zooming factor. The zooming factor range is between 0.1 
(very tiny) and 3.5 (large). 
"e" must be the last command of every control program and means end.
"#" Comments start with # and last till the end of line. 
The system is not case sensitive. 

Example:
# Automatic generated file (Mon Jul 08 12:43:30 MET DST 1996)
l
13.5
10
10
s
25
z
1.5
f
0
0
0
0
0
0
f
0
-33.1397
23.7784
0
9.36132
0
f
-43.0761
-26.211
-1.94342
0
28.1545
-43.0761
f
-51.3402
-18.5244
-22.2129
0
40.7374
-51.3402
f
0
0
0
0
0
0
e