How to make your first robot

dtb · June 2, 2011, 9:26pm

what happened now? check

what happened now? check batteries carefully!

robotgoose · June 3, 2011, 6:36am

Ok
Ok, you meen recharging them?

ignoblegnome · June 3, 2011, 7:38am

I see you’ve misplaced the

I see you’ve misplaced the reply button again. ; j

Can you please be more specific? “It’s not working again” doesn’t provide enough information for us to help you. Is it the same problem where you get an error trying to connect? Is it the identical error or something different? Have you tried the same troubleshooting steps that fixed it last time?

sshrihari · June 8, 2011, 12:05pm

Problems with Gp2D12

well I made the start here robot. I had a problem with the sensors. I am using a GP2D12 sensor. now th problem is that its not recognizing all objects in front of it near or far. please help with this problem

ignoblegnome · June 8, 2011, 12:17pm

To get help, you need to

To get help, you need to provide more info than you have. We need to see a clear, detailed, in-focus picture of your connections. A more in-depth description of your problem would help too. A video of your robot in operation showing the problem would be great too.

sshrihari · June 9, 2011, 5:15am

Actually, I had the Start

Actually, I had the Start her erobot Done after some days of work, It starts to crash with the walls and cannt recognize it. Yesterday at evening I found out that the Infra red Transmitter in the camera looked dull. I rewired it properly, sent a debug command and found that thr b0 value is constant nearly 50. Please help me with this problem.

sshrihari · June 9, 2011, 5:15am

Actually, I had the Start

Actually, I had the Start here erobot Done after some days of work, It starts to crash with the walls and cannt recognize it. Yesterday at evening I found out that the Infra red Transmitter in the camera looked dull. I rewired it properly, sent a debug command and found that thr b0 value is constant nearly 50. Please help me with this problem.

ignoblegnome · June 9, 2011, 9:57am

To get help, you need to

To get help, you need to provide more info than you have. We need to see a clear, detailed, in-focus picture of your connections.

sshrihari · June 10, 2011, 5:33am

Here are some Pictures of

Here are some Pictures of the problems. As I am not a good Solderer, I may have not soldered the pins properly. here are some pictures of the soldered pins. if any of the 4 pins are soldered properly. please tell me. and can u guess any other scenarios of the problem. Please help me

fritsl · June 10, 2011, 6:12am

Your soldering looks

Your soldering looks fine.

What happens if you run a debug without anything connected, and then put your finger on the pins? Does the value change?

PS: Please use REPLY, and do not post a new comment each time, thanks.

sshrihari · June 10, 2011, 7:36am

Yes the value changes. But

Yes the value changes. But when I connect the GP2D12 it doesnt recognize anything in front of it.

ignoblegnome · June 10, 2011, 7:46am

Did you at any point connect

Did you at any point connect the Sharp sensor to the pins backwards? Because you may have fried it if you did.

Also, did you have the unused analog inputs shorted to V as instructed in the directions?

sshrihari · June 10, 2011, 9:08am

I Dont think so. it used to

I Dont think so. it used to work very well. but when it didnt recognize walls its transmitter starts to glow dull. I even changed the batteries. but it still glows dull

ignoblegnome · June 10, 2011, 3:55pm

Also, did you have the

Also, did you have the unused analog inputs shorted to V as instructed in the directions? If you leave the unused analog inputs pins floating, it can lead to unpredictable responses. (Please check this first before moving on with your troubleshooting.)

Regarding the IR transmitter appearing darker in your camera, that is possibly a valid symptom, and possibly not. If the ambient light level in the room was different, the output of the IR transmitter might appear different.

What sort of readings do you get when you run debug as you place a flat piece of white paper at various distances from the Sharp sensor?

nanorobotgeek · June 10, 2011, 5:18pm

Its coming

Hey guys, I finally ordered the robot and it should be coming on monday the 20th of June.That means that I probally wont post any comments for another 2 weeks or so.

ignoblegnome · June 10, 2011, 6:02pm

I will alert the press.Just

I will alert the press.

Just kidding you. I look forward to seeing your robot in a few weeks!

sshrihari · June 11, 2011, 5:44am

I have shorted the pins .it

I have shorted the pins .it just shows 0 when i run debug as you place a flat piece of white paper at various distances from the Sharp senso

ignoblegnome · June 11, 2011, 9:40am

I suspect that you have

I suspect that you have fried your sensor somehow. The fact that it used to work (you said you hadn’t changed anything, I think) and now it doesn’t, together with the facts that you get readings when you place your finger on the analog pins and only read 0 with the Sharp sensor attached lead me to this conclusion.

Thank you for patiently answering all my questions. I tried to eliminate all other possibilities before concluding you had a dead sensor. If someone wants to offer an opinion, it is welcome.

I’ve never fried one before, but I know many people have. It only takes a moment of reverse voltage to do it. They should really have included a diode for reverse power protection.

My advice at this point is not be be discouraged. You have learned a lot at this point. Look at this post from Catus and see how he and his daughter dealt with the same setback. You could replace the sensor with a new one, or a different sensor, or a bump switch. Learn and have fun!

mohamed123 · June 12, 2011, 6:52pm

hi gys, am trying to

hi gys,

am trying to make the robot,and i started finding the materials,but unfortunately i did’nt find it in my country,so please help me get it,

ignoblegnome · June 13, 2011, 10:33am

I understand your problem.

I understand your problem. The cheapest shipping option to Egypt from Solarbotics is $42! I don’t have an anwer for you, but I do have advice.

You’ll have to do some research. Go to the Solarbotics page linked in the tutorial above, and make a note of the parts list in the LMR bundle. You’ll have to search around for a source (or sources) with good shipping rates for you. Try to get as many of the parts from one source as you can, because the incremental cost of a few more items won’t affect shipping much, but if you have to order from 3 or more shops, the shipping will be expensive.

Here’s a list of some online shops to check. Here’s a list of other forum posts on a similar subject. If you find some good sources that aren’t listed, feel free to add them.

There are some substitutions you could make if you aren’t finding the identical parts listed. Here are some examples:

L293D motor driver (substitute Texas Instruments SN754410 for a drop-in replacement)
Sharp Range Finder (some alternatives discussed here)
Servo (Just about any standard servo will do; be sure it is NOT a continuous rotation servo.)
GM9 motors (You can substitute other small DC gear motors; look for gear ratios between 100:1 (faster) and 200:1 (slower).)
Wheels (You can make wheels or find a substitute that fits your selected motors.)
DIL 330 x 8 Resistor Array (You actually only need a single 330 ohm resistor for the project.)

If you find a source and have a question about a specific part substitution, feel free to ask.

If you have a lot of trouble locating the Picaxe 28x1 processor and project board, you could even go for a different processor platform. In that case, you will not be able to use the example code in the start here page or the specific board instructions for this project. So this would be a big departure from the start here robot. I would only advise this if you simply cannot find an afforable source for the Picaxe and the board, but there are choices available to you for something else, like an Arduino. There are some examples of Arduino based robots inspired by the start here robot, if you search this site for them.