Educational Robot System SW-007 SKY WALKER Manual: Model SW-007 © 2007 AREXX Engineering -1-
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.
1. PRODUCT DESCRIPTION SKY WALKER 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.
2. SOLDERING 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 the instructions in this manual exactly to avoid problems. The correct tools already do half of the job! 2.1 Necessary Tools: Soldering iron (15 to 30W) Electronic Solder 0,8- bis 1mm Use an electronic soldering iron about 20 to 30 Watt. A soldering iron with more power can overheat sensitive components and the PCB traces.
2.2 Soldering techniques: Only use lead free ROSIN CORE solder! Never use any liquid or paste flux! PASTE Correct position for professional soldering Hold the iron like a pencil and only heat the component wire for a few seconds. 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! 4. Take away the soldering iron. DO NOT MOVE the component or PCB! 5.
2.3 Troubleshoot soldering mistakes: Cold PCB Not enough solder Solder is attached to the component wire but not to the PCB copper. Solder did not flow Cold component Bridge of solder Solder is attached to the PCB Copper but not to the component wire.
3.
Component Assembly PCB symbol Circuit symbol PHTR E C E Transparent or black C Switch Bottom view gnd sig gn d sig Microphone ECM Gnd is connected with the metal body Lamp Red Terminal pin MOTOR (terminal) M1, M2 SW (terminal) S1, S2 Motor + Battery (not included) -8- No symbol
3.1 List of electronic parts: Resistors 0,25 Watt; 5% Marking: Quantity: … 15 Ω … 1 KΩ … 3.9 KΩ … 27 KΩ … 47 KΩ … 100 KΩ … 2.2 MΩ R13 R1, R3, R7, R8 R2, R4, R12 R11 R10 R5, R6 R9 (Brown, Green, Black, Gold) (Brown, Black, Red, Gold) (Orange, White, Red, Gold) (Red, Violet, Orange, Gold) (Yellow, Violet, Orange, Gold) (Brown, Black, Yellow, Gold) (Red, Red, Green, Gold) 1 pc. 4 pcs. 3 pcs. 1 pc. 1 pc. 2 pcs. 1 pc.
3.2 The soldering job: 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 semiconductors like transistors and LEDs.
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. Please notice! We did not draw the lamps on this PCB! But it is realy important that the lamp legs are covered with a tube so there will be no shortcut! PREPARATION 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.
3.4 Electronic trouble shooting PROBLEM CHECK The lamps do not light. • Check the polarity of the battery. • Check the battery (is it full). • Check the polarity of the battery holder. The lamps do light but the Sky Walker does not react on noises. • 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.
4. Information electronic parts 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.
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.
Transistor 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.
IC = Integrated Circuit "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 different 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.
5. ELECTRONICS 5.1 Blockdiagram Power supply & Lamps section Lightsensor section Motor section Filter section Timer section Microphone sensor section 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. 5.
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.
Lightsensor section Power voltage Signal 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.
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.
Self-tapping screws (Parker) A self-tapping screw looks similar to a wood screw. When you screw it in a hole, it can cut the threads at the same time. Never try to screw it down all the way for a first time, because it may easily become stuck or you will damage its head. Tapping screws always have a sharp point, sometimes with a small carve. They look almost the same as screws which we use for wood, only the thread is more fine. The best way is to screw it in and out a bit. 1. Screw in 2.
6.1 List of mechanical parts: Please check all parts before you start assembly! Screw long Screw short M3x30 4 Pcs. M3x20 2 Pc. Nut M3 M3x12 6 Pcs. Rubber Washer Washer M3 18 Pcs. 4 Pcs. Spring washer 8 Pcs. M3 Screw M2 Pipe spacer Joint strip Metal Washer M3 2 Pcs. Nut M2 Crank 2 Pcs. M3 L Bracket 1 Pc. Crown gear 2 Pcs. Flat spur gear big 1 Pc. Assembled PCB 1 Pc. ø3x5 10 Pcs. Motor Leg set Flat spur gear small 1 Pc.
6.2 Instructions mechanical assembly For the assembly of the motor you need; First always collect all the parts, as mentioned in the "parts you need list", before you start the assembly! Install the motorbase and switch 1 pc. Motor 1 pc. Pinion gear (for motor) 1 pc. Switch 1 pc. Chassis panel 1 pcs. Motorbase 1 pc. Self-Tapping screw M2.3x5 6 pcs. Screw M2x5 4 pcs. Nut M2 4 pcs.
Assembly of the left and right sidepanel: To assemble the sidepanels you need; Assemble in numerical order: Sidepanel Left 2 Pcs. Sidepanel L & R 4 Pcs. L Bracket 4 Pcs. M2x5 screws Sidepanel Right Important! Axes on this side! NOTICE! The L Brackets should be assembled very straight to the side panels. Install gear shaft and crank: For this assembly you need; Cranck 1 Pc. Sidepanel Left 1 Pc. Pipe spacer Ø 3x5 1 Pc. Gear shaft 1 Pc.
Assembly of the sidepanels: 1 Pc. Sidepanel left 1 Pc. Sidepanel right 1 Pc. Pipe spacer Ø 3x5 1 Pc. Crank For the assembly of the sidepanels you need; Push the right sidepanel, pipe spacer and crank on the gearshaft. Hit slightly with the hammer, do not hit the terminals! OR BETTER, Push the gear on the shaft with your hands. See drawing. Ø 3x5 Cranck WARNING! Make sure that the cranks are 100% parallel.
Install the back legs to the sidepanels: M3 nut To install the back legs you need; M3 spring washer ! Top Notice the correct position in the crank! 1 Pc. Assembled side panels 2 Pcs. Assembled back legs 2 Pcs. Spring washer M3 2 Pcs. M3 nut ! Below Right back Left back WARNING! Make sure that the rear legs are installed into the cranks 180º apart (see drawing). Top Below Install front legs to the side panels: To install the front legs you need; M3 springwasher 1 Pc.
Install the joint strip of the front legs: To install the joint strip you need; 1 Pc. Assembled side panels 2 Pcs. M3x12 screw 2 Pcs. Spring washer M3 2 Pcs. M3 nut 2 Pcs. Ø 3x5 pipe spacer M3x12 Ø 3x5 Ø 3x5 Assemble the joint strip as shown on the drawing. Left back M3x12 Final assembly rear legs: For the final assembly you need; 1 pc. Assembled side panels 2 Pcs. M3 x 30 screw 2 Pcs. M3 nut 2 Pcs.
Installing the gears: To install the gears you need; Crown gear 1 Pc. Assembled side panels 1 Pc. Chassis panel 1 Pc. Crown gear with pinion 1 Pc. Flat spur gear with pinion BIG 1 Pc. Flat spur gear with pinion small 4 pcs. M2x5 screw Install the gears in numerical order 1-2-3. Flat spur gear BIG Flat spur gear small To make this assembly step more clear we have omitted the right side panel from this drawing.
7. TEST OF THE SKY WALKER 7.1 Mechanical test: This is a very simple test to see if the legs are moving. Connect the battery directly to the blue and orange motor wire, as shown on the drawing. In this step the POLARITY is not really important! When the legs are not moving correctly, please use the table below to find the problem. PROBLEM The motor shaft rotates but the gears are not rotating. CHECK The gears are possibly not correctly assembled. SOLUTION Install all gears again.
7.2 Final assembly: For the final assembly you need; 1 pc. Assembled Chassis 1 pc. Assembled PCB 3 pcs. M2,6x6 selftapping screw Insert the four wires to the hole in the PCB and install the PCB with the 3 selftapping screws to the chassis.
FINAL TEST AND ADJUSTMENT OF THE SKY WALKER; *) Switch on the robot, the lights start glowing. 1) Clap in your hands. 2) The Sky Walker should walk forwards for a few seconds and then stop automatically. 3) Shade the light sensor with your hand 4) The Sky Walker should walk forwards for a few seconds and then stop automatically. You can adjust the sound sensor sensitivity with VR1. You can adjust the light sensor sensitivity with VR2.
8. INFORMATION ABOUT GEARS The mechanics of the SKY WALKER ROBOT consists of two parts. The first part is the gear box, which takes care that the power from the motor shaft is converted to the crank. The second part is to convert the rotation of the crank into a movement of the feet. The transmission of power Gears, transmission belts, shaft, crank, chains: They all can transmit power. In the Sky Walker, four gears transfer the motor power into the crank. Such a transmission is called a gear box.
Appendix A AC AND DC POWER SOURCES 1.5 Volt battery Type AA or AAA On page 15 we already gave some information about the battery power source, but... there is more to explain about this item. The voltage of a battery is a quite low DC voltage. It is not dangerous when you touch it. The mains power voltage on a wall socket in our homes however is a VERY DANGEROUS AC voltage of 120 or 230 Volts (depending on the country you live in).
PERSONALIZE THE SKY WALKER If you like, you can personalize the Sky Walker. You can cut symbols and characters from paper (or colored tape) and fix it with transparent tape or glues, This way you can simply make a personalized Sky Walker. You can also use a special paint which is suitable for plastics! You will have a lot of fun making your own unique robot! The personalized Sky Walker on this picture was made by Mara from Nijmegen the Netherlands. Visit our Website: www.arexx.
