Society of Robots - Robot Forum
Electronics => Electronics => Topic started by: sohailsameja on March 07, 2013, 12:25:39 PM
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is the connection in the diagram corect for the black line follower mode of the $40 robot.This is the actual way iam going to solder them im not using the dip pins please confirm whether this will work.
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Standard protocol for message boards is to use lower case type. Your all CAPS subject lines are stressing me out, man.
Go easy on the caps and I'll give consideration to answering your questions.
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sorry,have changed it,just love the caps button and shift will go easy from now on.
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please confirm for pin 7 and 10 (does it go to vcc)
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In cases like Your's datasheet sure helps a lot --> http://www.ti.com/lit/ds/symlink/l293d.pdf (http://www.ti.com/lit/ds/symlink/l293d.pdf) ;)
If You connect everything as in the picture above two lower Half H-Bridges will be ON all the time and two upper Half H-bridges will be ON or OFF depending on output of Your sensors. All that means that if upper Half H-Bridge is OFF - motor spins, if it's ON - motors stops. If this is desired behaviour, then it's all right.
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Ok, im not really good with h-bridge termings i will just post the instructions from the original tutorial here.i dont have male header pins(impossible)to find hence i wanted a direst connection.
you will understand more below
(http://i305.photobucket.com/albums/nn236/pratheekn/image039.gif)
in the above picture you can see the header pins are to be connected to pins 2 & 15(sensor input) and pins 7 & 10(input)
later in the tutorial 4 wires are cut and the following instructions are given
Once done, cut fivefour 5 cm long wires and add molex connectors to each using the method given at www.societyofrobots.com/electronics_wire_connector.shtml (http://www.societyofrobots.com/electronics_wire_connector.shtml) Solder two of these wires to the 1K resistors. From these wires we will get high or low inputs from the sensors to drive the motor Solder the remaining two wires to the red wire of the battery cap.
now these positions are seen below the ones to the battery cap are connected to pins 7 & 10 and the others to the latter.
(http://i305.photobucket.com/albums/nn236/pratheekn/image014-1.jpg)
my question is can i solder(join) pins 7 & 10 to 8 & 9 as it is to the + terminal of battery and solder pins 2 & 15 directly to the resistor to ease my work and hence not use header pins.The diagrem initially posted describes my plans on soldering please confirm that
Thanks
P.S:i will ONLY use it as a black line follower.
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If You're asking if you can solder directly to the pin and skip the header - then yes, You can.
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Thanks alot i will solder them directly to the pin,One thing i dont understand is why pins 7 and 10 are connected to (+) terminal(vcc) and usually its input from sensor array.Could you tell me
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I already partially explained it in one of my previous posts. Also, datasheet is Your friend, it explains it very well.
However, if You want to be spoon-fed, here it is ;D In Your application intention is to have each motor spinning only one direction (one clock-wise, another counter-clock-wise), to achieve that author decided to clamp one side of each H-Bridge HIGH (keep them constantly ON), that causes motor to spin to the desired direction whenever the other side of H-Bridge is OFF (internally connected to the GND). When top side (due to sensor signal) is switched ON, both sides of motor get equal voltage, hence potential voltage across motor terminals becomes 0V, hence motor stops.
It would be useful for You to better understand how H-Bridge works:
--> http://www.societyofrobots.com/schematics_h-bridgedes.shtml (http://www.societyofrobots.com/schematics_h-bridgedes.shtml)
--> http://www.dprg.org/tutorials/1998-04a/ (http://www.dprg.org/tutorials/1998-04a/)
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thanks alot,most people tell me that pin 7 and 10 are usually for sensor input butthe author connected it to vcc,you explained me why.Thanks alot im ready to solder it that way and let me keep my fingers cross. :)
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Thanks alot im ready to solder it that way and let me keep my fingers cross. :)
Better don't hold Your fingers crossed while soldering, might ruin what You solder ;D
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:) :D :) ;D
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Final Word
Pins 1,7,8,9,10 are connected to Red wire of battery cap(Vcc)
Pins 2,15 connected to sensor input(left and right respectively)
Pins 3,6,11,14 connected to left and right motors respectively
Pins 4,5,12,13 connected to blackwire of battery cap(Gnd)