AREXX Engineering & JM3 Engineering SKY WALKER SW-007 User manual

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SKY WALKER
©2007 AREXX Engineering
Manual: Model SW-007
Educational Robot System SW-007
SKY WALKERSKY WALKER
©©
2007 AREXX Engineering2007 AREXX Engineering
©© 2007 AREXX Engineering©©
Manual: Model SW-007Manual: Model SW-007
Educational Robot System SW-007Educational Robot System SW-007

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Contents
1. Product description Sky Walker 3
2. Soldering 4
2.1 Necessary tools 4
2.2 Soldering techniques 5
2.3 Troubleshoot soldering mistakes 6
3. Electronic components 7
3.1 List of electronic parts 9
3.2 The soldering job 10
3.3 Electronic circuit test 11
3.4 Electronic trouble shooting 12
4. Information electronic parts 13
5. Electronics 17
5.1 Block diagram 17
5.2 Explanation black diagram 17
5.3 Function description of electronic parts 18
6. Mechanics 20
6.1 List of mechanical parts 22
6.2 Instructions mechanical assemby 23
7. Test of the Sky Walker 29
7.1 Mechanical test 29
7.2 Final assembly 30
8. Information about gears 32
A. Appendix A 33
© English translation (July 2007): 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.
The specification, shape and size of the product are subject to change without prior notice.
Technical assistance
during the construction
of the robot:
www.arexx.com
Manufacturer:
Jama Co., Ltd.
Tachung TAIWAN
Importer:
AREXX Engineering
ZWOLLE The Netherlands
© 2007 AREXX Engineering
When you have a pre-soldered
Robot (Model SW-007A), please
start with Chapter 6 on page 20.

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The Sky Walker is a striking robot with two sensors. One sensor watches the light
intensity, the other listens to sounds. When there is a sound or light effect, the Sky
Walker reacts on it by walking for a few seconds and then it automatically stops.
High on his four legs, the Sky Walker walks kind of wobbly. It looks as if he is walking
on clouds. Therefore, his name Sky Walker could not be more appropriate.
With this educational robot project, everybody can learn the basic principles of electro-
nics. Building the robot already brings a lot of fun. You feel great building a real working
electronic system out of all separate parts, which responds to changes in light and
sound.
Specifications:
Power voltage : 1.5 Volt
Power source : 1 Penlite battery (not included)
Power consumption (moving) : About 200 mA
Power consumption (at rest) : About 10 mA
Height : 135 mm
Diameter : 105 mm
Warning
uNo return is possible after having opened the bags with components and pieces
u Prior to the assembly read the manual thoroughly.
uBe careful when using tools.
uKeep this kit away from young children during construction and operation.
(They might get hurt by the tools or swallow small components).
uObserve the correct polarity of the battery.
uKeep the battery dry. When the Sky Walker gets wet remove the battery and let the
Sky Walker dry for some time.
uRemove the battery when you are not using the Sky Walker for a longer period.
u Children below 14 should only assemble this product with the help of adults.
1. PRODUCT DESCRIPTION SKY WALKER

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Before you start soldering we will give you some advise and instructions:Before you start soldering we will give you some advise and instructions:
Please read the complete soldering instructions before you start. Work accurately and follow thePlease read the complete soldering instructions before you start. Work accurately and follow the
instructions in this manual exactly to avoid problems.instructions in this manual exactly to avoid problems.
2.1 Necessary Tools:2.1 Necessary Tools:
Soldering ironSoldering iron
(15 to 30W)(15 to 30W)
2. SOLDERING
The correct tools already
do half of the job!
Soldering standard with a wet
sponge to clean the tip
Electronic SolderElectronic Solder
0,8- bis 1mm0,8- bis 1mm
Use an electronic soldering iron about 20 toUse an electronic soldering iron about 20 to
30 Watt. A soldering iron with more power30 Watt. A soldering iron with more power
can overheat sensitive components and thecan overheat sensitive components and the
PCB traces. When the power is too low, sol-PCB traces. When the power is too low, sol-
dering is hard and the solder will not flow well.dering is hard and the solder will not flow well.
Normally you also should have a solderingNormally you also should have a soldering
standard to store the iron safely and a spongestandard to store the iron safely and a sponge
to clean the tip of the soldering iron.to clean the tip of the soldering iron.
Use thin electronic rosin core solderUse thin electronic rosin core solder
Use thin electronic rosin core solderUse thin electronic rosin core solder
with a diameter of about 1mm. Do notwith a diameter of about 1mm. Do not
with a diameter of about 1mm. Do notwith a diameter of about 1mm. Do not
use liquid flux or an flux solder paste foruse liquid flux or an flux solder paste for
electronic circuits.electronic circuits.
Use a safe and solid standard Use electronic tools (150 mm).
Electronic screwdriver set
Always use the right type and size screw-Always use the right type and size screw-
driver you need the philips type for M2driver you need the philips type for M2
and M3 screws.and M3 screws.
Desoldering wick
To suck solder from a PCB to remove
components for small repairs.
Electronic cutter &Electronic cutter &
flatnose plierflatnose plier

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Only use lead free ROSIN CORE solder!
Never use any liquid or paste flux!
PASTE
Hold the iron like a pencil and
only heat the component wire
for a few seconds. Only add a little solder
each time
1. Preheat the solder area which
must be soldered AND the
component wire with the tip of the
iron. Do NOT overheat it!
2. Add some solder to the
soldering area and
component wire but NOT
TOO MUCH!
3. Remove the solder and let
the hot liquid solder flow.
4. Take away the soldering iron.
DO NOT MOVE the component
or PCB!
5.Cut away the long component
wire just above the soldering spot.
The END RESULT is a nice and
shiny soldering spot which is
attached to the PCB copper and
component wire.
Correct position for professional soldering
Please NOTICE the correct positioning of the components, see the drawings below:
WRONG GOOD
2.2 Soldering techniques:

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Cold PCB Not enough solder
Solder is attached to the
component wire but not to
the PCB copper.
Solder did not flow
Solder is attached to the
PCB Copper but not to the
component wire.
Cold component Bridge of solder
Wire bridge Perfect solder connection
Two separate components are
connected with a wire to each
other making a short cut
Two separate solder spots
are connected to each other
making a short circuit
The soldering surface looks
nice and shiny!
When the trace is broken or the path is damaged,When the trace is broken or the path is damaged,
remove the mask on the copper trace with a screwdriverremove the mask on the copper trace with a screwdriver
or a knife and bend the component wire to the trace.or a knife and bend the component wire to the trace.
Solder a piece of wire from trace to trace or fromSolder a piece of wire from trace to trace or from
component to trace.component to trace.
The PCB is made of a copper trace on a non-conductive substrate which connects
the components, who are soldered to solder paths, electrically with eachother. Copper
surfaces which will not be soldered are often coated with a mask to make it solder
resistant. This mask also protects the copper against oxidating. When we overheat the
copper traces or solder paths, the copper may vaporate or loosen from the substrate.
To repair this we must remove the protective mask carefully with a screwdriver or
small knife. See below how you can repair a damaged PCB.
2.3 Troubleshoot soldering mistakes:

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3. ELECTRONIC COMPONENTS
Variable ResistorVariable Resistor
(Potentiometer)(Potentiometer)
ResistorResistor
Ceramic capacitorCeramic capacitor
Electrolytic
capacitor (ELCO)
Transistor
-
+
B and E are just an
example, position can
change per type
NPN type
PNP type
Component Assembly PCB symbol Circuit symbol
When the component has a marking near the legs the polarity is extreme important !
Assembly with the wrong polarity can dammage the component or the complet circuit!

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PHTR
Lamp
Motor
Terminal pin
+
SwitchSwitch
Microphone
ECM
gnd
sig
sig
gnd
MOTOR (terminal) M1, M2
SW (terminal) S1, S2
Component Assembly PCB symbol Circuit symbol
Transparent
or black
Red
Battery (not included)
No symbol
Gnd is connected
with the metal body
Bottom
view
C
E
C
E

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3.1 List of electronic parts:
Resistors 0,25 Watt; 5% Marking: Quantity:
… 15 Ω R13 (Brown, Green, Black, Gold) 1 pc.
… 1 KΩ R1, R3, R7, R8 (Brown, Black, Red, Gold) 4 pcs.
… 3.9 KΩ R2, R4, R12 (Orange, White, Red, Gold) 3 pcs.
… 27 KΩ R11 (Red, Violet, Orange, Gold) 1 pc.
… 47 KΩ R10 (Yellow, Violet, Orange, Gold) 1 pc.
… 100 KΩ R5, R6 (Brown, Black, Yellow, Gold) 2 pcs.
… 2.2 MΩ R9 (Red, Red, Green, Gold) 1 pc.
Ceramic capacitors Marking: Quantity:
… 22 nF C3, C4 (223) 2 pcs.
… 1 nF C6 * Already soldered to the motor ! *1 pcs. (motor C)
Semi conductors Marking: Quantity:
… A1015 or A733 TR1, TR5 (2SA1015 or 2SA733) 2 pcs.
… C1815 or C945 TR2, TR3, TR4 (2SC1815 or 2SC945) 3 pcs.
… D2001 or D734 TR6 (2SD2001/2SD2120 or 2SD734) 1 pc.
… Phototransistor PHTR (SFH309) 1 pc.
Divers Marking: Quantity:
… PCB AREXX DG-SKY (arexx) 1 pc.
… Microphone EMC (Condensor type for PCB) 1 pc.
… Switch SW (Slide switch with wires) 1 pc.
... Termininal pin S1, S2, M1, M2 (1 mm Typ) 4 pcs.
… Motor M (1,5 Volt DC Motor) 1 pc.
… Motor cable With terminals at each end (Blue, Orange) 2 pcs.
… Battery holder VCC (1 pc. AA type) 1 pc.
... Light bulb Lamp1, Lamp2 (red color lamp) 2 pcs.
... Black wire For lamp assembly (About 8 cm wire) 1 pcs.
ELCO’s Marking: Quantity:
… 3.3 µF C1, C5 (3.3 µF/50V) 2 pcs.
… 100 µF C2 (100 µF/16V) 1 pc.
Wire preparation:Wire preparation:
Wire preparation:Wire preparation:
Pre-solder the copper wire. This step
makes it more easy to solder the wire
later on.
Remove about 5mm of the
plastic wire insulation
Twist the copper wires
when necessary
Put the soldering wickPut the soldering wickPut the soldering wick
on the solder path.on the solder path.on the solder path.
Heat the wick and theHeat the wick and theHeat the wick and the
path with the solderingpath with the solderingpath with the soldering
iron and the copperiron and the copperiron and the copper
braid of the wick willbraid of the wick willbraid of the wick will
suck the solder.suck the solder.suck the solder.
Desoldering
When the wickWhen the wickWhen the wick
removed all theremoved all theremoved all the
solder from thesolder from thesolder from the
path, pull back thepath, pull back thepath, pull back the
wick and thewick and thewick and the
soldering iron simul-soldering iron simul-soldering iron simul-
taneouslytaneouslytaneously
When you made a soldering failure, you can easily remove the mistaken component with wick.
Variable resistors Marking: Quantity:
… 100 KΩ VR1, VR2 (104) 2 pcs.
5mm

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1) Start with the resistors.
2) Then we solder the potentiometers to the PCB.
3) After that, we solder the 4 terminal pins.
4) In this step we solder all ceramic capacitors.
First please check if all parts are complete
with help of the parts list on page 9 and the
circuit on page 18.
The markings on the PCB show exactly at
which location you should solder the parts. If
you need more information, please check the
drawing of the PCB.
We always start to solder the lowest and non
critical parts, these are normally the resistors
and ceramic capacitors, and finish with the
higher critical parts like Elco's and semi-
conductors like transistors and LEDs.
We advise to cut the component wires
directly after soldering, so they will not be in
the way when you start soldering other parts.
In the following steps we will solder the more critical parts. It is important to solder the
correct type and the correct polarity. Take care not to overheat these parts with your
soldering iron.
5) Start with the Elcos and notice the correct polarity with the plus and minus marking.
6) Solder the transistors, be sure you solder the correct types and correct polarity.
7) Solder the microphone and pay attention to the correct polarity!
8) At last you can solder the PHTR. The polarity is very important!
Final PCB soldering are the lamps and the battery holder
The LAMPS must be soldered with 25mm leg length.
3.2 The soldering job:
The last part is the battery holder and also
here the polarity (red + and black wire -)
is realy important.
The battery holder itself is fixed to the PCB
with double sided tape.
THE POSITION AND POLARITY OF THE ICs, ELCOs, DIODES, TRANSISTORS, LEDs AND PHTR ARE MOST IMPORTANT,
OTHERWISE THE ROBOT MAY NOT FUNCTION CORRECTLY OR IN THE WORST CASE, COMPONENTS GET DAMAGED!
are the lamps and the battery holderare the lamps and the battery holder
Bend the lamps 15mm and 10mm length,
same way as shown on the picture.
** IMPORTANT NOTICE FOR THE LAMPS:
Very important is to put a tube (20mm) over each leg of the LAMPS after
you solder it! This tube will protect the LAMPS against a short circuit.
Tube 20mm
The LAMPS must be soldered with 25mm leg length.The LAMPS must be soldered with 25mm leg length.
Lamp preparation:
1) Cut 25 mm wire and remove insulation
5mm (see page 9 wire preparation).
2) Solder the wire to the lamp.
4) Put the tube over the wires so there will
be no shortcut between the wires.
3) cut 2 pcs of
20 mm tube.
Micophone!
Gnd is connected
with the metal body

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First we have to connect the switch to the PCB. Connect the 2 black wires of the switch to the SW
terminals on the PCB.
Now we have to connect the motor to the PCB. Connect the orange and blue wire to the motor terminals and
connect the other end of the wire to the motor terminals on the PCB. The position of the terminals is not so
important.
Insert the battery.
PLEASE NOTE THE POLARITY! (+ and -).
At last: Adjust the variable resistors into the middle position.
3.3 Electronic circuit test
Before you start with the mechanical assembly we do a simple test to check the function of the electronic circuit.
When you adjust the variable
resistors, please use a good fitting
screwdriver. Always rotate it very
slowly without any force.
*)*)
Switch on the robot, lamps will glowSwitch on the robot, lamps will glow
..
1) Clap your hands.1) Clap your hands.
2) The motor2) The motor
should rotate for a few seconds and then automatically stop.should rotate for a few seconds and then automatically stop.
3) Shade the light sensor with your hand.3) Shade the light sensor with your hand.
4) The motor4) The motor
should rotate for a few seconds and then automatically stop.should rotate for a few seconds and then automatically stop.
NOTE!
You can adjust the sound sensor sensitivity with VR1.
You can adjust the light sensor sensitivity with VR2.
PREPARATION
TEST
To improve the sensivity of the light
sensor you must put a small piece
(5mm) of tube over the PHTR sensor.
See drawing above
Please notice!Please notice!
Please notice!Please notice!Please notice!
Please notice!Please notice!Please notice!
We did not draw the lamps on this PCB!We did not draw the lamps on this PCB!
We did not draw the lamps on this PCB!We did not draw the lamps on this PCB!We did not draw the lamps on this PCB!
We did not draw the lamps on this PCB!We did not draw the lamps on this PCB!We did not draw the lamps on this PCB!
But it is realy important that the lamp legs areBut it is realy important that the lamp legs are
But it is realy important that the lamp legs areBut it is realy important that the lamp legs areBut it is realy important that the lamp legs are
But it is realy important that the lamp legs areBut it is realy important that the lamp legs areBut it is realy important that the lamp legs are
covered with a tube so there will be no shortcut!covered with a tube so there will be no shortcut!
covered with a tube so there will be no shortcut!covered with a tube so there will be no shortcut!covered with a tube so there will be no shortcut!
covered with a tube so there will be no shortcut!covered with a tube so there will be no shortcut!covered with a tube so there will be no shortcut!
covered with a tube so there will be no shortcut!covered with a tube so there will be no shortcut!
covered with a tube so there will be no shortcut!covered with a tube so there will be no shortcut!covered with a tube so there will be no shortcut!
covered with a tube so there will be no shortcut!covered with a tube so there will be no shortcut!covered with a tube so there will be no shortcut!

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3.4 Electronic trouble shooting
The lamps do not light.
The lamps do light but the Sky Walker does not react
on noises.
The Lamps do light but the Sky Walker does not react
on differences of light intensity.
Transistors get very warm.
• Check the polarity of the battery.
• Check the battery (is it full).
• Check the polarity of the battery holder.
• Check the sensitivity of the microphone.
• Check the parts and solderings involving the
microphone circuit: ECM, R1, VR1, R8, C4,
TR3, TR4 and TR5, TR6.
• Check the sensitivity of the lightsensor.
• Check the polarity of the PHTR.
• Check C1, R2, VR2, TR1, TR8, R4-R7 and C3
• Check the transistors type, position and polarity.
PROBLEM CHECK
- When there is a problem ALWAYS check the battery first: Is it full?
- Check the wire connections, only in good wire connections the current can flow freely.
- Try to establish if you have a mechanical problem or an electronic problem.
- Use the trouble shoot tables in this manual.
- Check all electronic parts, see if it is the right type on the right position and check polarities too!
- Check all solderings: Do the parts and the PCB traces make good contact?
- When a problem cannot be solved, best way is to disassemble the robot and build it again. Follow the
instructions in the manual very accurately.
Tips and Tricks

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The value of a resistor can be identified by coloured rings. The first and secondThe value of a resistor can be identified by coloured rings. The first and second
ring describe a number and the third ring is a multiplying factor, of which youring describe a number and the third ring is a multiplying factor, of which you
should multiply the previous number. The fourth ring shows the accurancy of theshould multiply the previous number. The fourth ring shows the accurancy of the
resistor value, which means the possible deviation of the value in %.resistor value, which means the possible deviation of the value in %.
The relation between them is called "OHMs LAW" :
VOLTAGE = CURRENT TIMES RESISTOR.
Current calculation; I = U : R
Resistor calculation; R = U : I
Voltage calculation; U = I x R
POWER = Voltage times Current
Resistor
The resistor restricts the current in an electronic circuit. When you use Ohm's law, you
also can see that they can reduce the voltage in a circuit. When you imagine the current
as a water flow in a garden hose, the resistor creates the same effect as pressing in the
middle of the water hose. The water does not spray out of the hose so hard anymore.
1 2 3 4
Example: A resistor with colored rings Brown (1), Black (0), Orange (thousand) and Gold has a value of
10000 Ohm (10KΩ) and 5 % accurancy.
TIP:
A trick to remember the the resistor colorcode is;
Buy Better Resistance Or Your Grid Bias May Go Wrong (The first letter mentions the color letter)
4. Information electronic parts
Quantity: Symbol: Value (SI unit) :
Current I Ampere (A)
Voltage V Volt (V)
Resistor R Ohm (Ω)
Power P Watt (W)
Lamp
A very common part which you can find in each household. Because of the low voltage
we are using an incandescent light bulb. This type transfers electricity in light and heat.
The efficiency is poor, because the heat is a waste of power which we do not want.
Therefore we use more and more LEDs as a lamp. They have a much better efficiency.
Color Value Multiplication
Black 0 1
Brown 1 10
Red 2 100
Orange 3 1000
Yellow 4 10000
Green 5 100000
Blue 6 1 Million
Violet 7 10 Million
Grey 8 100 Million
White 9 1000 Million
Gold x 0,1 of 5 % accurate
Silver x 0,01 of 10 % accurate
Some basic
principals and
important
formula's used
in electronics

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Variable resistor
Besides the normal resistors we also have the variable resistor which is also called
potentiometer (potmeter).
The variable resistor is available in many types and shapes. One of the most familiar
variable resistors is the volume regulator in a radio. The type which is used in our robot
is directly placed on the PCB. The maximum value of a potmeter is always given. The
potmeter in our robot is used to change the amplification of the sound and light sensor.
Capacitor
Capacitors can store electronic energy and when you require it they can offer it back
without great lost. An other characteristic is that they can block a DC current and let an
AC current pass. They will have a certain resistance for AC currents. The symbol for
a capacitor is C. The value of a capacitor is named capacitance and the unit is Farad
(F). Normally the value of a capacitor is very small and is expressed in Nano-, Micro- or
Picofarad:
Abreviation Meaning Value
1µf 1 micro Farad 0,000001 Farad
1nf 1 nano Farad 0,000000001 Farad
1pf 1 pico Farad 0,000000000001 Farad
There are many coding systems for capacitors. Ceramic and mylar capacitors which we
normally use, have value numbers printed on it.
Electrolytic capacytor (ELCO)
The Elco is a polarized (meaning; direction-depending) capacitor. The manufacturers
put several markings on this capacitor to recognize the Plus and Minus pin of this
capacitor. Normally one pin is longer (plus) than the other. The minus pin shows a
white marking on it.
Diode
The diode allows the current to flow only in one way (from Anode to Cathode). When
the current wants to flow in the other direction, it will be blocked.

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We already mentioned the battery on page 13. The one we are using in the Sky Walker
has a voltage (V) of 1.5 Volts. Voltage means the difference of the electrical potential
between the PLUS and MINUS pole of a battery. When you see electricity in
analogy with water, you can imagine that voltage is almost the same as pressure.
When the battery is in a closed circuit, the electrons will flow from - to + and generate a
current (I) which will flow in the circuit. The current value is measured in Ampere.
The Power consumption (P, in Watts) in a circuit is Voltage x Current: P=UxI
When the Sky Walker is moving, it will use a current of 200 mA (0.2A). The battery
voltage is 1.5 Volt.
P = U x I P = 1.5V x 0.2A
So the Sky Walker's power consumption is 0.3 Watt = 300 mW
The transistor is a semiconductor which can be used as a switch and for amplification.
The transistor has three terminals: Basis, Emitter and Collector. These three terminals
are normally marked with the first letter; B, E, and C. The transistor is supplied in many
types and shapes. There are 2 important main types: the PNP- and NPN-Transistors.
The flow in the NPN-Transistors is different than it is in the PNP-Transistors.
You can also imagine the transistor as a water tap
(Basis) in a waterstream, which flows between
A (Collector) and C (Emitter). The water flows;
• from Collector to Emitter in a NPN-Transistor
• from Emitter to Collector in a PNP-Transistor
With the tap regulator which you can imagine as the Basis,
we can regulate the Flow between A and C.
It is even possible to switch the flow on and off.


When you imagine above waterflow, you can understand that with a small current on
the Basis, we can regulate the flow of a big current between Emitter and Collector.
Now you can also imagine that we can switch off the flow between Emitter and
Collector completely so it will act like a switch.
Transistor
Aand Ccan be the Transistors
E (Emitter) or C (collector),
depending on the NPN or PNP
type.
Battery See also Appendix A
for more information.

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"Integrated Circuit" means a complete electronic circuit on a silicon chip. With the name
IC we describe a complete circuit which normally contains several transistors and other
electronic parts like resistors and capacitors in one building block. There are many dif-
ferent types and shapes of ICs. A few ICs together often build a complete product. For
example only one small receiver IC and a small amplifier IC can make a very small but
complete radio.
This electronic part is so important in modern electronics that we have to mention it
even though we do not use it in the Sky Walker robot.
Microphone
Motor
A motor transforms electrical energy into mechanical
energy. A well-known technical frase for mechanical
energy is kinetic energy. Kinetic comes from Greek
(kinesis) and means motion.
IC = Integrated Circuit
The microphone is maybe the most familiar part in the Sky Walker. Almost everybody
knows what a microphone is. We see it often on TV and all radio makers and pop-
stars have to use it. But do you also know how it works? The microphone changes
soundwaves into electronic signals. These electronic signals can be used in electronic
circuits for example in an amplifier. In the Sky Walker, the microphone detects sounds
and when the Sky Walker detects a sound, the electronic circuit will be activated.
Phototransistor (PHTR)
The PHTR is a light sensitive device. It works a bit like a transistor but instead of a
basis which controls the flow with a current it has a light sensitive basis. With a PHTR,
the current flow between Emitter and Collector is controlled by the intensity of light.
E
C
LED = Light Emitting Diode
The name LED already says it all, "Light Emitting Diode" which means a diode who
produces light. This diode has the same features as a normal diode but it will light when
a current flows from Anode to Cathode. There are many different colored LEDs and
there are all so many different shapes, sizes and brightnesses. LEDs are often used in
control panels but also in traffic lights because their power consumption is very low.
A
C
AC

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5. ELECTRONICS
5.1 Blockdiagram
Big electronic schematic diagrams can be very complicated. To simplify such a complex diagram we often use
a blockdiagram. In a blockdiagram we imagine several electronic circuits as a block with their own function. So
with the above blockdiagram we can see the function of the Sky Walker electronics. We will explain each block
more detailed now.
Motor
section
Power supply &
Lamps section
Filter
section
Timer
section
Microphone
sensor section
Lightsensor
section
Power supply and Lamp section
Provides all electronic circuits with power. The Lamps are an ON/OFF indicator
Light sensor section
Detects a difference in light intensity
Sound sensor section
Detects sounds
Timer section
An RC network, regulates the walking time
Filter section
Filters the disturbing power supply signals from the motor
Motor section
Switches the Motor ON and OFF
5.2 Explanation blockdiagram

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5.3 Function description of electronic parts:
Above you can see the complete circuit diagram of the Sky Walker. As you can see it is
much more complex than the blockdiagram we discussed on the previous page.
Microphone section
The microphone section consists of an electronic condensor
microphone ECM which detects the soundwaves. The electronic
signal goes through a volume regulator VR1. The capacitor C4
has 2 functions. First it blocks the DC voltage from the power
supply. Second and together with resistor R8 it is a filter so the
sound of a handclap can be detected better. A condensor micro-
phone can only work with a power supply. This power is supplied
by R1.
Power & lamps section
This is the most simple, but also the most important section. In
the blockdiagram you can see that the power section is connec-
ted with all other sections. The reason is simple, all electronic
circuits need power to work. The power of the Sky Walker comes
from a 1.5 Volt battery and can be switched on and off with SW.
The 1.5 Voltage is too low to use LEDs, so instead we have used
2 small light bulbs. So the only function of the lamps is to see if
the Sky Walker is switched ON or OFF. So, here the lamps are
used as an indicator light.

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The phototransistor can see the difference between light and dark. When it is light,
there is a small current flow through the PHTR and the Collector to Emitter is almost
fully open. When it is dark, there is a very small current flow, and C/E is almost closed.
The current (and the sensitivity of this circuit) can be adjusted with VR2. The elco C1
takes care that it will not react on very little and short light changes. Because the
current flow difference between light and dark in the phototransistor is so small, we
have to amplify this signal in two transistor stages, TR1 and TR2. The capacitor C3
and Resistor R7 both have the same function as C4 and R1 in the microphone sensor
circuit.
Power voltage
Signal
Lightsensor section
Timer section
The signals from the sound and light sensor will activate
the timer circuit. If there is no sound and not a big light
difference detected, the input signal on the base of TR3
is low. This means that the signal on the collector of TR4
is high. Because of a positive feedback from C5, the TR3
base will stay low for a while and the collector output of
TR4 stays high. The duration of this positive feedback is
called RC time. The RC time can be calculated R9xC5 =
time; so 2200000 x 0,0000033 = 7.26 seconds
Input
Motor section
In the explanation of the timer section we just calculated that
there will be a low signal for about 7 seconds. This low signal
will activate TR5. This is an amplifier because the current
of the timer section is too small to drive the transistor TR6
directly. TR6 will function like a switch and the motor will start
to rotate for these 7 seconds.
Filter section
This important section takes care that no disturbing signals
from the motor will enter the other sensitive electronic circuits.
Often there are disturbing signals with RC networks and small
capacitors. We can filter the power supply lines from distur-
bing signals.

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6. MECHANICS
IMPORTANT: First read all the instructions about the mechanics !
Follow the step-by-step instructions for the mechanical assembly as shown in this
manual. Read and work very accurately. This is the best way to avoid assembly
failures. When you follow these instructions and study the drawings and comments
carefully, you have a big chance the robot will work directly and without any problems.
Also a great help is the picture on the package. You can see very clearly how the robot
should look like. Best is that you only take out the parts from the packages and frames
when you need them! Sometimes parts or bags are numbered. All parts fit perfectly so
you do not need to use force to assemble this robot! Do not hurry and once more, best
is to read all instructions first before you actually start to assemble.
Possible extra tools which can be handy:
Hobby knife Tweezer Small plastic hammer
How to cut the plastic parts
To take out the plastic parts from a
frame, use a sharp hobby knife or a
cutting plier. Cut carefully and take
of the bosses with a knife to make it
smooth.
Do not cut parts from a frame
when you do not need them
directly!
Assembly of a gear to an ax
When you install a gear or a pinion to an ax or shaft, like
the pinion to the motor shaft, you must be very careful. Be
100% sure you put the right gear onto the right ax. Best way
is always to press the gear on the shaft with your hands.
When you cannot manage it this way, use a very small plas-
tic hammer. When you use a hammer, you can protect the
gear or the shaft by putting a piece of wood or carton
between the hammer and the part you will hit on.