Arexx MRAI-999HB User manual

MRAI-999HB
©2003 AREXX - HOLLAND
EDUCATIONAL ROBOT HARDWARE & SOFTWARE
MANUAL

2
Movit and Elekit are registered trade marks of EK Japan Co., Ltd.
AREXX is a registered trade marks of AREXX Engineering, Zwolle, Holland
© English translation (October 2004): AREXX Engineering (NL).
This description is protected by the laws of copyright. Any partial or total reproduction of the contents is
prohibited without prior written authorisation of the manufacturer:
AREXX Engineering - Zwolle (NL).
The manufacturer and distributor cannot be held responsible for any damages occurred by mishandling,
mounting mistakes or misuse due to a non-respect of the instructions contained in this manual.
Technical assistance during the
construction of the robot:
www.arexx.com
© 2002 AREXX - The Netherlands
1. Product Description 3
2. MRAI-999 Installation 4
3. The electronic circuit 5
4. Software installation 6
4.1 Software Installation and configuration 6
4.2 General purpose program for SAM 7
5. MRAI Hobby setup 8
6. MOVIT or OWI Robot arm software 9
6.1. Software 10
7. Interactivity 18
Contents

3
1. PRODUCT DESCRIPTION
Warning
•No return is possible after having opened the bags of components and pieces
• Prior to the assembly read the manual thoroughly.
• Be careful when using tools.
• Keep away from young children They might get hurt by the tools or swallow small
components.
• Observe the correct polarity of the power supply.
The MRAI is a serial port Input/Output controller, it can be controlled with the
supplied Windows robot arm software or a terminal emulator (like. Windows
Hyper Terminal or LINUX Minicom) and a Personal Computer. MRAI has 20
switch transistors to control the MOVIT or OWI robot arm motors. There is
1 optocoupler input so the robot arm can react on signals from the outside
world.
The MRAI controller is commanded with very simple instructions. With the
Robot Arm software application you can control the MOVIT or OWI Robot
Arm directly or you can make your own program in a Basic computer
language. In this Basic program language you can use the IF/THEN and
GOTO statements. Of course, the optical inputs can also be used. A few
example programs and an educational mode will help you to learn the Basic
programming step by step.
Specifikation:
Power : 3 pcs AA batteries
Voltage : 4,5 Volt
Current : About. 100 mA
Height : 40 mm
Lenght : 100 mm
Width : 70 mm
To control the MOVIT-OWI robot arm

4
Feet Distance holder
Nut
1.
Assemble the 4 distance holders with 4 nuts to the MRAI PCB,
Then screw the 4 feet with a screw to the distanceholders.
2.
Connect the 25-pin RS-232 cable with your PC and with the
MRAI.
3.
Connect the atcable with the MOVIT or OWI robot arm and with
the MRAI.
4.
Insert the 3 pcs AA batteries.
5.
Start software installation
Screw
2. Installation of the MRAI

5
The concept of this kit is simple and straight forward. The core of the
system is the IC U1, a 16F628 PIC microcontroller.
We have selected this processor because of the available in- and
outputs. The number of in- and outputs is convenient for our purpose
and, in addition, it features a serial interface.
We have pre-programmed the IC in such a way that it can process all
commands we send through the serial interface. Moreover, the proces-
sor can drive the Transistor switches and monitor the optocoupler input.
When a robot arm motor is activated by a transistor a red or green LED
will light up.
IC U1 (MAX232) handles the level change of the TTL and RS232
signals. The optocoupler IC U2 is required for galvanic seperation of
the sensitive circuitry from the inputs.
You can also completely reset the system at any time via the reset
switch.
When the kit receives data from the PC, the “Data” LED light up.
3. THE ELECTRONIC CIRCUIT
Please NOTICE:
There is a new Software VERSION available at:
WWW.AREXX.COM --> Robotics -->
Movit robot arm --> Downloads

6
4.1 Software installation and conguration
It is recommended to close all other running applications before starting the
Installation!
When you insert the Software CD, your standard Web Browser will appear,
showing a CD-Menu (This happens only if you have activated the CD-Autorun
function of Windows). If this does not happen, you can start the CD-Menu
manually with the Windows Explorer, too. (<CD-ROM> - “start.htm“)
You may start the Software Installation with the CD-Menu or directly from the
Explorer. (Directory <CD-ROM> - “software\control\“, maybe you will have to
copy all the installation les to a directory onto your hard drive rst.)
The installation of the software will be automatically done by clicking on install.
It is also possible to start the software installation with windows explorer, just
click on SETUP.exe to start the installation.
The Interface program can be found in the START menu under PROGRAMS–
INTERFACE.
Double click on the interface icon to start the program.
A popup screen will appear when the hardware is not connected.
Click [OK]
Now the Mainmenu will
appear (see g.4.1.).
Fig. 4.1.Main menu
4. Software installation

7
Only when the hardware is detected, you will see the hardware status
in the title bar of the main menu, for example: “COM X – SAM”. The
X shows the COM port on which SAM is detected. When you connect
the hardware later.
(ATTENTION: ALWAYS SWITCH SAM or MRAI OFF BEFORE
ATTACHING/DISCONNECTING IT TO/FROM A PC! OTHERWISE
SAM or MRAI AND THE PC MAY BE DAMAGED!
Usually this does not cause any damage, but it is saver to handle
it as described!), it is possible to detect it with a simple command.
There is no need to restart the software for hardware detection, just
click on the RED spot at the right side of the main menu bottom.
In the main menu the software language can also be selected.
4.2 General purpose controlling program for SAM
The function of the SAM controller software is to switch the relay contacts
after an event (status change).
Fig. 4.2. Controlling program

8
5. MRAI HOBBY SETUP
Instead of the SAM-01 controller you can also use the MRAI Hobby controller
to operate the Robot Arm. This is a low cost controller which works with the
SAME SOFTWARE.
The Movit Robot Arm Interface HOBBY is already assembled.
This stand alone controller fully operates on batteries. The robot arm is also
battery operated. An external power supply is not possible. The MRAI Hobby
is connected between the Robot Arm and a computer (instead of the standard
switchbox).
The MRAI HOBBY operates with the standard interface Robot Arm
software. See chapter 7.
MRAI
Flat cable
RS232 cable

9
9
6. MOVIT or OWI Robot Arm software
MODE
The program distinguishes between two operating modes:
A button mode where you can control the robot directly with the operation
buttons and the programming mode (simple or advanced), where you can
enter commands as text lines with buttons or the keyboard.
Please start the Interface Program (link in the start menu)
and choose your desired language!
After that, start the Robot Arm program module (click on the button).
The MOVIT Robot Arm software works with the following hardware;
- SAM-01 Controller in combination with the interface IK108
- MRAI Hobby controller
- NONE (DEMO MODE)
Please NOTICE:
There is a new Software VERSION available at:
WWW.AREXX.COM --> Robotics -->
Movit robot arm --> Downloads

10
BUTTON MODE
In this mode, you can control the Robot Arm through the buttons:
* BASE
* SHOULDER
* ELBOW
* WRIST
* CLAMP
Start position
At the program start, all counters are set to zero.
The starting position of the robot is now:
• Base in the center position
• Shoulder in the highest position
• Elbow in the highest position
• Wrist in the center position
• Clamps closed
If needed, you might have to bring the robot manually into
the start position.
With this method, you can easily test the way how the robot works and
try out more complex movements before you actually program the com-
mands.
The operating buttons clearly display which movement you are con-
trolling.You control the Robot Arm with the left and right mouse but-
ton. Please note that the arm moves in direction of the arrow that is
displayed when the key is activated. If the arm moves in the opposite
direction, the voltage polarity is wrong. In this case you have to reverse
the positive and negative connections of the motor driving voltage.

11
PROGRAMMING MODE
The programming mode is divided into 2 modes:
* SIMPLE MODE
* ADVANCED MODE
SIMPLE
This mode is a convenient method for beginners who do not have real
programming experience. In this mode, you learn the basic commands.
The program lines are generated according to a set pattern allowing
you an error-free programming.
ADVANCED
In this mode you edit the pro-
gram lines directly. You write the
text file in an external editor and
copy it via the key board into the
programming field.
Start position
The counter displays the time in seconds.
(Note: The counter does not count in seconds).
At the counter stand of zero, the arm is in its start position. You can set
the robot to another start position by proceeding as follows:
• Bring the robot arm in the required start position by the operating
buttons.
• Click on the OFFSET button
• After a movement of the Robot Arm you can
bring it back into the start position by clicking
on the RETURN button.
1 ACTION, BS(RGT=5), EL(UP=2)
2 ACTION, BS(LFT=5), EL(DN=2)
3 ACTION, SCH(UP=5), WR(LFT=2)
4 ACTION, CL(OPEN=9)

7.2 PROGRAMMING:
12
At first, we will describe the most important commands:
LINE NUMBER
All commands start with a line number. The numbers are
increased by 1 at every new line. It is possible to insert lines
afterwards.
ACTION
This command indicates the start of a task.
It is followed by a command or the element to be moved.
)
The round bracket closes the task while ( opens the task. In other
words: Tasks are put between round brackets (...).
IF
An IF command is always followed by a THEN command.
These commands use sensor signals. A program line is built up
as follows:
IF Sensor 1-4 is on or off THEN .....
After the IF-THEN command, you can continue with an ELSE
command. This means that your program will continue with the
ELSE task if the IF condition has not been fulfilled.

13
FILE
Store the program on the hard disk
Import the program from the hard disk
Finish the program
Example:
1 IF SSR1=OFF THEN 2 ELSE 3
This condition is fulfilled if SSR1 (sensor 1) is not active. In this
case, the program will go to line 2 or else line 3.
If you drop out the ELSE task and the condition is not fulfilled, the
program will remain on this line until this condition is fulfilled.
GOTO
This command brings you to the beginning of a program line.
Example: GOTO 1 (Go to line 1).
NEW LINE
To write a program line
ERASE LINE
To remove a program line
ADD LINE
To add a program line
START
Start the program

SIMPLE MODE:
This chapter explains how you can write simple programs in
the simple mode.
14
The programming in the simple mode always starts with NEW
LINE. After having pushed this button, you
can choose between the following commands:
ACTION, IF and GOTO.
Now we can choose which part should move, in which direction
and how long this movement should last. You can give the dura-
tion in 1/10th second behind the dot e.g. 3.2 secondes. Close the
command line by a ). Then you can add the line by ADD LINE.
If we choose ACTION, the following screen is displayed:
EXAMPLE Programming in the simple mode:
NEW LINE ACTION ELBOW DOWN 2 )
ADD LINE
This input sequence generates the following programme line:
1 ACTION, ELL(DN=2)
When executing this programm i.e. START, the elbow will go down for 2
seconds.
A new line adds another command line to the program

15
In addition to the ACTION commands there are also the IF -
THEN and GOTO commands. The IF-THEN command always
processes input signals (of the sensors).
In programming mode you can also process the input signals from the sen-
sors. The input signal can be simulated by the red switches on the upper bar
of the screen. This is very useful to test a program. Thick the small white box
on the top right next to the four red, square fields. Four switches are displayed
allowing to switch the input signals on
and off.
We start a new line but instead of ACTION, we
will choose the IF command:
The screen display changes into the following mode. You will
notice now the new sensor fields 1 to 4. These sensors normally
transmit input signals to the robot system. These input signals
can also be simulated by switches.

16
The advanced mode is the programming method for those who
already have some knowledge about programming. You can write
the program in a text editor and copy it into the program field.
Of course, you can also input the lines directly into the field via
the keyboard.
ADVANCED MODE
The abbreviations for the different language elements are:
A program line always starts with the number of the line.
This is always followed by a command or a decision.
The commands and statements are summed up in the following
table:
Activity Type
ACTION Command
IF THEN/ELSE Decision
GOTO Command
1 IF (SSR1=ON) THEN 2
2 ACTION, BS(RGT=5), SCH(UP=5), EL(UP=5), WR(RGT=5), CL(OPEN=4)
3 IF (SSR1=ON) THEN 4
4 ACTION, BS(LFT=5), SCH(DN=5), EL(DN=5), WR(LFT=5), CL(CLS=4)
5 GOTO 1

The programming possibilities of the ACTION command are:
Activity,(Abbrev.) Element Direction Time *
ACTION, ( ACTION) BASE (BS) LEFT/RIGHT, (CW/CCW) -*.*, *.*
ACTION, ( ACTION) SHOULDER (SH) UP/DOWN, (UP/DN) -*.*, *.*
ACTION, ( ACTION) ELBOW (EL) UP/DOWN, (UP/DN) -*.*, *.*
ACTION, ( ACTION) WRIST (WR) LEFT/RIGHT, (LEFT/RIGHT) -*.*, *.*
ACTION, ( ACTION) GIPPER (GR) OPEN/CLOSE, (OPEN/CLS) -*.*, *.*
17
The programming possibilities of the decision IF-THEN are:
Decision Element (Abbrev.) Statement Line #.* Decision ** Line #.*
IF THEN SENSOR1, (SSR1) TRUE/FALSE **** ELSE ****
SENSOR2, (SSR2) TRUE/FALSE **** ELSE ****
SENSOR3, (SSR3) TRUE/FALSE **** ELSE ****
SENSOR4, (SSR4) TRUE/FALSE **** ELSE ****
The programming possibilities of the command GOTO are:
* The star (*) in this column is a figure 0 .. 9.
** The ELSE (with line number) in the IF THEN-statement
can be dropped
Activity Line #.*
GOTO ****

18
IMPORTANT:
As only 8 relays are available to control the 5 motors of the Robot
Arm via the controller, we used a trick. Normally we would have
planned 5 relays to control the 5 motors and supply 4.5V positive
or negative to the motors (All motors use a common ground).
As a consequence of this trick, the motors cannot turn all at the
same time. Some relays control two motors at the same time and
these motors can only turn in the same direction when they are
addressed at the same time.
The software makes sure that the motors are driven in sequence
during conflicts.
Within one program line you can pull together several actions and
processes (see example)
1 ACTION, BS(CW=5), EL(UP=2)
2 ACTION, BS(CCW=5), EL(DWN=2)
3 ACTION, SH(UP=5), WRST(LEFT=2)
4 ACTION, GR(OPEN=9)

19
Use of the inputs
7. INTERACTIVITY
The software makes sure that the motors are driven in sequence
during conflicts.
By the use of suitable sensors you can control the Robot Arm
interactively in its environment.
The sensors are connected to the input of the controller. The
inputs of the controller contain opto-couples that protect all
following circuit parts.
The opto-couple and therefore also the inputs are only activated
(1) by a certain voltage level of about 2 to 5V. If there is no
voltage or a too low voltage present at the input, this input is not
active (0).
1 IF (SSR1=TRUE) THEN 2
2 ACTION, BS(CW=5), SH(UP=5), EL(UP=5), WRST(RIGHT=5), GR(OPEN=4)
3 IF (SSR1=TRUE) THEN 4
4 ACTION, BS(CCW=5), SH(DWN=5), EL(DWN=5), WRST(LEFT=5), GR(CLS=4)
5 GOTO 1
EXAMPLE:
ROBOT SYSTEM WITH SENSOR INPUT
SENSOR INPUT

20
APENDIX