Author Topic: PCB 50$ Robot (Need help) (Read 967 times)

zwarte · « **on:** October 27, 2012, 04:49:47 AM »

Hi Guys,

I've made the pcb for the 50$ robot ( http://www.societyofrobots.com/member_tutorials/node/191 )

http://p32i.img-up.net/20121027_1d445.jpg
http://h64i.img-up.net/20121027_1d2e4.jpg

1. I dont know where to connect the 10 pin AVR Any ideas?
2. When i connect the power, nothing happens....
3. Where should i connect the servo's?

lrmall01 · « **Reply #1 on:** October 27, 2012, 02:20:12 PM »

Hi Zwarte,

I'll try to help but I think we will need more info in order to get your problems solved. Here are some initial comments.

1. I dont know where to connect the 10 pin AVR Any ideas?
- I'm not sure what you are talking about. What do you mean AVR - is this what you are calling your programmer? If so, the programming connection in this design is a 6 pin header. If you can provide more details we'll try to help.

2. When i connect the power, nothing happens....
- Nothing will happen unless you program the micro-controller. Have you done this yet?

3. Where should i connect the servo's?
- Re-read bullet #2 in the link you gave above. The 3 pin headers are for servos. Those 3 pin headers have a signal, power, and ground connection. Just line those up with the equivalent signals on your servo connector.

Hope this helps - if you can answer my questions I'll try to provide more suggestions.

Good luck!

zwarte · « **Reply #2 on:** October 27, 2012, 02:42:31 PM »

The only thing i've done so fare, is i made the pcb and soldered everything on it i need to programe it, the poin is i dont know how.

Here is the pdf that comes along maby it makes you a bit wiser. http://www.societyofrobots.com/member_tutorials/files/$50_1.zip File $50 Robot Top V1.1.pdf

Programmer:
I have an MySmartUSB http://shop.myavr.com/index.php?sp=article.sp.php&artID=42
Is the programmer fit to connect and to programe the chip on the board as designed? it's a 10 pin AVR connector, usb connected to pc. Where should i mount this avr on the pcb?

lrmall01 · « **Reply #3 on:** October 27, 2012, 03:49:45 PM »

Ok - that helps. I don't have a copy of Eagle to check the schematic for your board but what you need to do is re-map the 10 pin connector to the 6 pin connector labeled ISP on the robot board.

First, open the manual to your programmer, located here: http://www.myavr.info/download/produkte/mysmartusb_mk2/techb_mysmartusb-mk2_de_en.pdf

and scroll down to page 5. You'll see a diagram showing the pinout of the 10 pin header. You'll notice that there are many of them labeled as GND, so you don't really use all 10 pins. Basically the board you build is likely using 1 GND connection where the connector actually has it in 4 places.

Hopefully that make sense. Basically make sure that the signals match - unfortunately there doesn't look like there is a way to just plug your programmer in, you'll need to make some kind of adapter to convert the 10 pin over to the 6 pin.

zwarte · « **Reply #4 on:** October 27, 2012, 04:38:08 PM »

I've made it 6 pins now and connected it.

What i got not is Laptop USB>Mysmartusb (10pin) to my PCB (6pin)

I'm working now wih PonyProg o see if i can upload a hex file for my servo (0 degrees for modding)
The software isen't able o find the PCB. Power is connected and my the configuration is set on Com 3.

Do you have any tool to check the pcb functionallity?

zwarte · « **Reply #5 on:** October 27, 2012, 05:25:20 PM »

i think the pcb is completly fucked up, I'm thinking about maiking a new one. But i really hope this one will work. Any ideas of debugging the hardware? My 9v battery is only showing 6v on my multimeter. Remember this is my first time and it's a hobby.

I dont even know wich pin is + or - on the battery connecto. The tut just sais Battery pins.
And the on off button, i dont know wich direction is on or off. I would love to remake it but i need some help with a few small details as i said above.

waltr · « **Reply #6 on:** October 27, 2012, 05:28:51 PM »

Use your Voltmeter (small hand held DMM works fine) and measure the voltage into and out of the regulator (the tall, 3-pin device next to the power switch). The regulator output should measure +5V (red lead of meter with the black lead on a 'ground' pin (center pin of regulator).
Next measure the Vdd pin on the processor which should also be +5V.
The regulator into should measure the same as the battery and greater than 7V.

If any of these measure very low then disconnect to battery and use the Ohmmeter scale to look for shorts on the PCB.

The PCB and construction looks very nice. Good job.

[watch your language here or you may get banned]
Be patient and you will gets lots of help from the people in this forum.

lrmall01 · « **Reply #7 on:** October 27, 2012, 05:34:08 PM »

Hopefully you have a multi-meter where you can measure some voltages. If so, be sure to check the power and ground connections on the board to make sure they are correct.

Also see if the micro-controller is getting power and ground and perhaps the RESET line of the controller.

Another thing to try is put the meter in the mode to measure resistance and check the connection from the programmer to the micro-controller and other connections on the board. You want to make sure things that are supposed to be connected are connected and ensure things aren't shorted. For example, but the meter on the RESET line of the programmer and then put the other lead on the RESET line of the micro and ensure it is connected (some meters have a continuity mode where it will beep if the resistance is below about 20 Ohms). Open the schematic and use your meter to probe around and confirm the PCB is electrically the same as that shown in the schematic diagram.

Your comment about the 9v battery being at 6v makes me wonder if you don't have a short from power to ground somewhere. Are you sure you aren't measuring the output side of the voltage regulator? That 3 pin chip with the capacitors next to it will convert your 9v down to 5v for the micro-controller to work with.

Finally, I was looking at the photo of the bottom side of the board and you may want to trim the leads still hanging off the bottom to make sure they don't short to anything, if you haven't already.

I wouldn't make a brand new PCB. From looking at the bottom, it looks like it is etched OK. And even if it is wrong, some jumpers, etc. could likely fix it.

Hope this helps - let me know if you can find anything. Just be patient and keep in mind most of the fun in this stuff is working out these problems. If you don't view it as a kind of puzzle and enjoy figuring it out this stuff will probably drive you nuts!

zwarte · « **Reply #8 on:** October 28, 2012, 11:50:16 AM »

Well i've found 2 solding issues, and i know what on/off is and what + and - is.
But for now it's still not working i'm checking the circuit (hard time) since i'm a bigger with the muti-meter.

So bassicly i need to know the following:
-where i shoud connect the servo on the pcb.
-In wich format (Ohm,V) should i use to test the circuit.

waltr · « **Reply #9 on:** October 28, 2012, 01:33:22 PM »

Quote

-In wich format (Ohm,V) should i use to test the circuit.

re-read my post above and lrmall01's post.
Ohm is the unit of resistance and is used to check for short circuits and continuity.
V = Volts and is the units of Electrical Potential. This is use the measure Battery Voltage, regulator output Voltage.

In the "Robot Tutorials" is a very good beginner's tutorial on how to use a DMM in the Ohm and Volt scales.

Quote

-where i shoud connect the servo on the pcb.

There looks to be a row of 3-pin connectors that can be used for servos. Which one you use depends on the code written and loaded into the AVR processor.
Google "R/C Hobby servo" to learn what they require. Then study the schematic to see which connectors will supply the needs lines to the servo leads.

Did you trim the excessive wire leads from the bottom of the PCB yet? If not do it else they will cause a short circuit.

zwarte · « **Reply #10 on:** October 28, 2012, 02:16:44 PM »

Oke i'm kiling myself with knowledge atm but i'm getting ahead!.

I think i found and fixed al circuits, and i know what what dows on the pcb and where i should connect everything.

I've managed to upload the hex file to the chip (i think) but the servo (ADC0(5V)) does nothing, how can i debug this? Is there a way that i can send a piece of code to rotate the servo?

lrmall01 · « **Reply #11 on:** October 28, 2012, 06:09:13 PM »

First off, I just want to point out how far you have come since you first started. If you have indeed been able to download the hex file for the first time then that is quite an accomplishment!

As Waltr mentioned, which connector to use will depend upon the software programmed into the micro-controller. I'm assuming you are trying to build the Photovore robot as described in the $50 robot tutorial. If you review the SoR_Utils.h file you will find the subroutine for the servo control. This will show that the left wheel is controlled by the PORTD, Pin 0 and the right wheel is controlled by PORTD, Pin 1. These line up to pins 2 and 3 respectively. You can find this by viewing the schematic for your board or also by taking a look at the schematic from the $50 robot tutorial:
http://www.societyofrobots.com/images/sbs_avr_schematic.png

Take your multimeter and place the black lead on the black pin of the servo and put the red lead on the red pin of the servo - make sure those are about 5V. Then put the meter in resistance mode and put the red lead on the yellow pin of the servo and then put the black lead on pin 2 and then pin 3 to make sure it is indeed connected to the micro.

Hopefully you will find out that something isn't connected, because if you successfully downloaded the Photovore_v1.hex file and the servos are connected then they should indeed be turning.

Report back when you get a chance and we will see where to go next!

Webbot · « **Reply #12 on:** October 28, 2012, 08:58:19 PM »

And don't forget to read the rest of the pages in my tutorial where you got the board design from - there's a whole section on construction re testing as you go

zwarte · « **Reply #13 on:** October 29, 2012, 03:07:33 AM »

Yes! and again i've gained some progress. Oke i'm managed to command the servo. The issue is it wasen't on PD0 Neither PD1. I connected the servo on a other spot (under led 4pin spot. Bassicly the 4 pins is the following - + PD0 PD1 < Something went wrong with creating the pcb(Check first post for screenshot) <<<<<Important

2. but i am able to programe servo. and i modifeid the servo (Just dident understand step 5, the glueing part http://www.societyofrobots.com/actuators_modifyservo.shtml)

3. I have no idea what to do now, I have an working pcb and i have modded the servo what now? SHould i build the skeleton or?

lrmall01 · « **Reply #14 on:** October 29, 2012, 06:02:50 AM »

Step 5 is a bit tricky - the point is to center the servo - or to configure it so it "stops". If you don't do this then your servo's may not work right. You will want to program your micro with this .hex file: http://www.societyofrobots.com/downloads/hold_servo.hex

That will send the signal to the servo to make "stop". But depending upon where the potentiometer is set, it likely won't be stopped. You'll have to adjust it as shown in the tutorial until you find the sweet spot and then glue it.

I would de-bug your electronics first, before building the chassis since you have been focusing on that. The photovore basically looks for the status of the light sensors and drives the servos based off of that. So you should be able to hook up ALL your electronics (2 servos, two sensors) and confirm that the servos change direction when you apply and take away light.

Really no need to build the chassis until your electronics are working properly. Sounds like you are there, though, just need to confirm everything.

zwarte · « **Reply #15 on:** October 29, 2012, 08:23:25 AM »

Quote from: lrmall01 on October 29, 2012, 06:02:50 AM

Step 5 is a bit tricky - the point is to center the servo - or to configure it so it "stops". If you don't do this then your servo's may not work right. You will want to program your micro with this .hex file: http://www.societyofrobots.com/downloads/hold_servo.hex

That will send the signal to the servo to make "stop". But depending upon where the potentiometer is set, it likely won't be stopped. You'll have to adjust it as shown in the tutorial until you find the sweet spot and then glue it.

I would de-bug your electronics first, before building the chassis since you have been focusing on that. The photovore basically looks for the status of the light sensors and drives the servos based off of that. So you should be able to hook up ALL your electronics (2 servos, two sensors) and confirm that the servos change direction when you apply and take away light.

Really no need to build the chassis until your electronics are working properly. Sounds like you are there, though, just need to confirm everything.

Servo has been modded so now i got a working pcb and 2 modded servo's. Need to look wich electronic i should mound now an ideas? Adding light sensors right now.

lrmall01 · « **Reply #16 on:** October 29, 2012, 03:20:46 PM »

Quote

Need to look wich electronic i should mound now an ideas?

I'm sorry but I am not sure what that is supposed to mean. Please re-phrase it if you need an answer.

As far as what to do next, wire up your photo sensors and make sure you are seeing the voltage change on the A/D pins (27 and 28) with your multimeter when you change the light level.

Report back with what you find.

zwarte · « **Reply #17 on:** October 30, 2012, 04:27:35 AM »

I'm maiking the photo sensors, using an 100 ohm transistor. used multi-meter to calculate wich resistor to use.

Altough i'm having alot of confusion what to connect where on the pcb (2 Servo's), thank you for telling me where to connect the photo sensors.

Re-phrase:
I'm almost done with the photo sensors, soon i'll have a Pcb with 2 Servo's and 2 photo sensors connected on it. From that part on what should i do?

lrmall01 · « **Reply #18 on:** October 30, 2012, 05:57:09 AM »

Finish all of the electronics, since that is what have been working on thus far. Hook up your batteries and make sure everything works.

Once that is done go ahead with building the robot chassis - body, wheels - and mount everything.

zwarte · « **Reply #19 on:** October 31, 2012, 12:08:11 PM »

I ordered a few things so i can continue. And is there a file that contains details what should be connected on ADC5,PD2,PB0 etc??, because i'm unable to find it, The only files i have are these http://www.societyofrobots.com/member_tutorials/files/$50_1.zip.
I am requesting this, because i'm having a hard time figuring out what to connect where.

lrmall01 · « **Reply #20 on:** November 01, 2012, 11:33:32 AM »

I linked the schematic for the $50 robot in an earlier post - scroll back up and click it. If you are using the Photovore_v1 software, then that source code expects servos and photo-sensors to be plugged in according to that schematic.

Let me know if that isn't clear.

zwarte · « **Reply #21 on:** November 01, 2012, 01:24:09 PM »

Quote from: lrmall01 on November 01, 2012, 11:33:32 AM

I linked the schematic for the $50 robot in an earlier post - scroll back up and click it. If you are using the Photovore_v1 software, then that source code expects servos and photo-sensors to be plugged in according to that schematic.

Let me know if that isn't clear.

the schematic doesn't make it very clear, could u post it in a different style? for example my first post, paint editing can help.

i just read that i need to connect a 4,8v battery next to the 9v battery did i understand that correctly?

lrmall01 · « **Reply #22 on:** November 01, 2012, 05:41:46 PM »

The format is pretty simple - just look for the colored dots. Also, it clearly states which microcontroller pin needs to be connected. For example, the photo-sensor outputs go to pins 27 and 28 - it clearly says 27 and 28.

Regarding a 4.8 battery, that does not make sense to me. You don't need multiple battery sources, one 9v is sufficient.

zwarte · « **Reply #23 on:** November 05, 2012, 03:30:56 AM »

Quote from: lrmall01 on November 01, 2012, 05:41:46 PM

The format is pretty simple - just look for the colored dots. Also, it clearly states which microcontroller pin needs to be connected. For example, the photo-sensor outputs go to pins 27 and 28 - it clearly says 27 and 28.

Regarding a 4.8 battery, that does not make sense to me. You don't need multiple battery sources, one 9v is sufficient.

Well look at the "motor" 2 pins beside the 9v input, that circuit doesn't have a power supply. it's confusing

zwarte · « **Reply #24 on:** November 05, 2012, 11:46:12 AM »

completed the robot

lrmall01 · « **Reply #25 on:** November 06, 2012, 06:02:58 AM »

Quote from: zwarte on November 05, 2012, 03:30:56 AM

Well look at the "motor" 2 pins beside the 9v input, that circuit doesn't have a power supply. it's confusing

Maybe we are referring to different schematics. I am talking about the one located here: http://www.societyofrobots.com/images/sbs_avr_schematic.png

I don't see the word "motor" anywhere on this schematic.

Quote from: zwarte on November 05, 2012, 11:46:12 AM

completed the robot

Congratulations! Hope you enjoyed it and plan on building more projects in the future!

zwarte · « **Reply #26 on:** November 06, 2012, 05:43:27 PM »

Yes, i'm going to continue this, going to add 3 more photo sensors (2 front,left,right,back). after that an ir range sensor so it can harass my girlfriends cat