Fixing Grandpas Robot

FastEddie

New Member
Hello,
I was given one of my Grandpa's old solar robots he made. I'm trying to bring it back to life and get it to move around. My main thing now is that I would like to see the code on the chip so i know what it should do. I get some life from it but no movement yet. I made a short 2min overview video here:

Any help and advice bringing this back to life would be greatly appreciated!
 
Last edited:
By design, you can't read what's on the PICAXE chip. You can try searching the internet for
18m2 solar robot
and see if anything comes up. Since it's on perf board, it's either his own design or a copy of a project from a magazine or online. If grandpa had his own computer - probably, because you need a computer to program the chip, you could search it for files ending in ".bas" and see if you find the original code. Then you could search for other files in the same directory/folder to see if there is any other documentation or a reference to a magazine or web page.
Good luck!
.
 
By design, you can't read what's on the PICAXE chip. You can try searching the internet for
18m2 solar robot
and see if anything comes up. Since it's on perf board, it's either his own design or a copy of a project from a magazine or online. If grandpa had his own computer - probably, because you need a computer to program the chip, you could search it for files ending in ".bas" and see if you find the original code. Then you could search for other files in the same directory/folder to see if there is any other documentation or a reference to a magazine or web page.
Good luck!
.

Thanks for such a fast answer. I too thought about old computer files, but thought about it too late. The computer was donated.

I'll dig around the internet for old plans. If i learn anything new I'll post it.

If I cant decode it through manual testing, maybe I'll recode it myself. (I'll need to learn to code first lol)
 
Most people do NOT understand how much useful information might be on a computer that's "no longer needed" :-(
Intellectual works can be priceless - or at least point you in the right direction ;-)
 
Most people do NOT understand how much useful information might be on a computer that's "no longer needed" :-(
Intellectual works can be priceless - or at least point you in the right direction ;-)

Agreed. I hope to be able to figure out how it works without having to reprogram it. The code feels like a final fingerprint of his living on in the robot. I'm writing down all the things I get the bot to respond to at different switch positions. I'll post them later this week. Maybe someone can see a pattern that I can't.
 
Agreed. I hope to be able to figure out how it works without having to reprogram it. The code feels like a final fingerprint of his living on in the robot. I'm writing down all the things I get the bot to respond to at different switch positions. I'll post them later this week. Maybe someone can see a pattern that I can't.
I hope your efforts to understand the functionality go well, please let us know how you get on and if you need any support.
If you don't manage to get it working I would advise you keep the 18M2 with your Grandpa's code so it is preserved and you can return to the project in the future. I would use a separate 18M2 for any recoding. The 18M2 looks to be soldered directly onto the board (no socket) so removing is a bit trickier and would probably need hot air.

Do you see any infra red detectors mounted on the robot (see image here for an example: https://picaxe.com/thumbnail1f1e.jpg). Perhaps it is waiting for an IR input.
 
Thanks @bogbean I have some type of sensors on it (3 total) but I dont know if they are the same as the ones you point out.

I did however get the bot to move! (A little) it seems to be reorienting to the window. But I have not seen motion beyond that. I documented this and the corresponding switch positions and lights in the video attached. I'm going to leave it in this position for another 24 hours to see if it moves on its own after orienting to the window.
 
Very glad you've got the bot moving. My guess is that the two sensors on the front are light dependant resistors, they look to be angled slightly to each side of the forward direction so the difference in resistance between them would allow the robot to sense a light source direction. The solar panel is one flat plane so I don't think that alone can be used for light-finding. In your video it's hard to see what the sensor is on the rear. Could you post a close-up photo of it? We may be able to identify what it is.

I did a quick search for robots that look like this but I did not find any, yours looks to be very well constructed.
 
Very glad you've got the bot moving. My guess is that the two sensors on the front are light dependant resistors, they look to be angled slightly to each side of the forward direction so the difference in resistance between them would allow the robot to sense a light source direction. The solar panel is one flat plane so I don't think that alone can be used for light-finding. In your video it's hard to see what the sensor is on the rear. Could you post a close-up photo of it? We may be able to identify what it is.

I did a quick search for robots that look like this but I did not find any, yours looks to be very well constructed.

You're right! They are resistors. I'll attach a close up of the back sensor. Its the same as the front two. To test your theory, i turned the bot away from the light with the back sensor facing the light. Activated the switch, and it did a 180 and turned right back to the light source.

I had also left it on all night and around 4 am it just started to blink red and beep nonstop. No idea what it wanted but had to turn it off to sleep lol

I too looked for old kits or plans around this chip and could not find any. I think it was his own design. He was a computer scientist for the DOD for many years and worked with computers ever since they took up entire rooms. He would often desing electronic toys for us as kids out of scraps around the house.
 
I had also left it on all night and around 4 am it just started to blink red and beep nonstop. No idea what it wanted but had to turn it off to sleep lol
"Feed me" I would guess, that being its battery-low indicator.

Given it has a solar panel and presumably rechargeable batteries I would guess keeping itself charged is its 'primary directive'.

Hence it's a bit odd that it hasn't exhibited any random motion and gone on a hunt for light. The LDR suggests it would, and the bump detector wouldn't make much sense if it wasn't expecting to bump into things while doing so. It may be it's not in the mode to do that, or perhaps the batteries aren't charged enough for it to decide to go walkabout.

My guess is the toggle switch is a hard power on-off option, the slide switch selects a basic mode and the touch sensor selects the detailed mode., you may need more touches than throws to get it into its various modes, touch and holds rather than taps. From the first video a long tough may be a 'sleep' function. Throwing the toggle switch powers it off, then on, provokes a reset. The slide switch may be repurposing the Serial Out, may be a Serial In switch.

Partially dismantling and tracing where the wires go may help reveal what's connected to what.

I would consider grabbing a torch once night has fallen and seeing if you can find a mode to get it to follow the light around. Taping the bumper to see if you can make it react.
 
I would consider grabbing a torch once night has fallen and seeing if you can find a mode to get it to follow the light around. Taping the bumper to see if you can make it react.


Will do! I'll see if I can get it to search for the light and keep you posted. I do plan to open up the bot as much as possible to see if I can tell what is wired to what. That should give me some more clues on functionality.
 
Another thought, if you are willing to post your grandpa's name, any email addresses, or user names he may have used to - support @ picaxe . com - we may be able to check our records to see if we can find anything which might help towards discovering more about this robot or anything similar.

We won't use any personal information for other purposes and won't disclose any information discovered without your approval.
 
Another thought, if you are willing to post your grandpa's name, any email addresses, or user names he may have used to - support @ picaxe . com - we may be able to check our records to see if we can find anything which might help towards discovering more about this robot or anything similar.

We won't use any personal information for other purposes and won't disclose any information discovered without your approval.
That would be grand. I'll send you a note separately
 
Back
Top