“JavaBot”  LINE FOLLOWER ROBOT from Java, Indonesia

The line follower robot with wireless video camera.

I have designed it just for fun. First I want to know how the line sensor work. I used comparator IC using LM339, two H-bridge sensor using eight transistors, FCS9013, and four transistors, FSC 9012. For the sensor you can use LED and LDR as the light receiver. I changed the LDR sensor to IR sensor. I built this robot using only the analog comparator and IR sensor, no microcontroller. This is smart idea and very cheap approach.

You can download this PCB FILE (ExpressPCB file) 

Figure 1: main layout and sensor layout.

Bill of material :

R₁, R₇, R₁₃, R₁₄, R₁₅, R₁₆ 330 1/4W +/-1%

R₂, R₃, R₄, R₅, R₆, R₈, R₉, R₁₀, R₁₁, R₁₂             10K 1/4W +/-1%

R₁₇, R₁₈, R₁₉, R₂₀                                              150 1/4W +/-1%

VR₁, VR₂                                                         20K-50K

Led₁, Led₃                                                       LED(red) 3mm Led

Led₂, Led4                                                       LED(green) 3mm Led

Optocoupler                                                     2 piece

Q₁, Q₂, Q₃, Q_4, Q₅, Q₈, Q₉, Q₁₂                       FSC 9013       

Q₆, Q₇, Q₁₀, Q₁₁                                              FCS 9012       

U1                                                                   LM 339

Battery 9 volt                                                    1 piece

Motor DVD dc 5Volt                                       2 pieces

Tank toys for mechanic and wheel                    2 pieces

Sample expense in Rp.

		@	total
resistor	20	100	2000
VR	2	500	1000
led	4	300	1200
tr	12	250	3000
ic	1	3000	3000
optocoupler	2	3500	7000
PCB	1	3000	3000
tank toys	2	10000	20000
motor DVD dc 5 volt	2	5000	10000
battery	1	3500	3500
		total	53700

1 $US = Rp 9400

Finally I spent only 6-7 $US to build the robot.

Figure2: JavaBot, my first line follower robot without the microcontroller.

There are two line styles, white line on the black floor and black line on the white floor.

If you use black line on the white floor,  you can set the robot if the Right-Sensor is on the dark side or black line and Left-Sensor is on the floor it will go to forward (by swap polarity of the motor). If the Right-Sensor is on the floor and Left-Sensor is on the black line it will go to backward. Download this video for illustration. JavaBot.wmv

Figure3: Attach the wireless video camera to the JavaBot.

---

Any questions or suggestions, please contact me,
Tahan Prahara, prahara_satria@yahoo.co.id

 30 November 2007