Here's my latest Buggy-bot? and my best one so far, why?well having a good quality chassis is a start, rather then bits I've thrown together in the past. The build quality is very good, the motors while quite separate run at the same speed, well very close!!so it travels in a straight line and not a curve.Now when it hits a chair leg the tracks allow it to run up it, but then the tilt switch comes in to play and it reveses for a time and does a turn!This is also the first time I've used PWM to control the speed, it starts off slow but soon gains speed to 99%+, slows down when an object is detected, reverses and looks both ways for the longest clear run and goes for it, etc,etc.
But its not perfect! it still gets trapped under the radiator, or the front corners jam somewhere (may have to fit a bumper switch??) one of the driving gears has an hole in it, so thinking to use a (or 2, one per motor) slotted opto switch/s to detect motor stall!
The PCB's are my own, the top one being my version of the Picaxe shield, but with a 20M2, with memory and RTC, with the 20M2 all port pins are in line and brought out to the 8 pin headers in neat orderly rows (unlike the Arduino, which are all over the place). The bottom PCB has the L293 motor driver chip, sound, LED indicators......Batttery charging is in situ, 6xAA's give about 7.3V to the motors and a LDO 5V reg powers the rest.
I have more work to do yet, so work in progress.
Oh by the way! I'd love to have your comments, advice good or bad. Why not take a look at http://melsaunders.x10.bz
Regards
Mel.
: Navigate around via ultrasound, avaiding objects and crashes, most of the time!
Actuators / output devices: servo, geared dc motors
OK here’s my very first video, having been a photographer all my life, I have never been tempted by Cine or Video. I shot this on my Panasonic TZ-5 one of the last things I got from the photo shop where I used to work (Redundant & retired).
When it’s first switched on it makes a sweep of tones, then the US detector does a scan, it sits there bleeping and waiting to be started with a wave of your hand, and off it goes…I did another video where it ran up a chair leg and reversed, but this time he comes to a sticky end!!
Regards
Mel.
PS. Hope I can load this up OK. Oh well it seems I first have to upload it somewhere else!! Can I be bothered?? Not really in to all that Youtube kind of stuff. accept for watching this http://www.youtube.com/watch?v=J05oDDWm_-0
EDIT: Oh, I thought you were having troubles with having the video embeded. As I turn to look at the video link I’m disappointed to find it’s unrelated. :s So,… uploading to youtube, provided you have a google account is pretty much drag ‘n’ drop. That shouldn’t be too hard. Even I can do it Just give it a go.
Well, you can Edit your Original post and you should find there a Video section that is by default collapsed, just click it and post the youtube link above in one of the boxes. After that your video should be nicely embed in your original post
Sorry that was my taste in music. Just for you (No not really) I went and got myself a Google account, etc. I uploaded the video but not the one I had in mind, anyway this one will give an idea of how my buggy goes. My next step is going to be? Make a PCB for the top to carry an LCD module and driver…
Anyone any good with encloders! I hope to add an slotted opto switch to a gear that has an hole it it.
Come on chaps at least make me feel welcome and say something, if only booo!!
It seems to move very well. Also took a peek at your previous bots and they all have a very clean look. I like it
Oh, so I’ve come across as un-nice and un-welcoming?.. well I guess I can’t hide my true nature despite the usage of happy emoticons, so I’ll just go back to frowning again I wasn’t even aiming at it… really
Well, you know the saying “a picture is worth a thousand words”? then a video should be worth a 1000 times the frame rate, no?Around here we actually have another saying “Video or it didn’t happen!” Which is usually said playfully among the chaps here. However, when I asked for the video it was really out of general interest to see how it moved, and perhaps to best advise about the cavets you mentioned in the text (couldn’t make a mental picture myself and wanted to see the problem).
Btw, as for wheel encoders… that’s my greatest failure, yet. I’ve only tried optical, and perhaps because I went the full DIY route they were such a failure. I’ll try magnetic ones next, people have vouch for them and I believe in them, but haven’t got around to use them myself. Do a search here for “wheel encoders” and you’ll find several projects where they where used. In your particular case the major problem I see/image is spatial constrain to install said encoders.
Nice and clean construction. I really like your custom picaxe board and your chassis. I too have a picaxe 20m2 and what i really love about it is its pin configuration, the top four pins of the IC ie pin 1, 2, 19 and 20 are for power and programming and rest can be used in any way, it makes it easier to make custom boards or breadboard circuits due to this. More memory and and an RTC on board makes it even more awesome! I will like to see some more pictures of your bot. Can you tell me what chassis have you used?
No you don’t come over as nasty or anything like that! Where did you get that idea?? In fact you have been the only one to take the time and look at at bot, SORRY robot! and comment on it, which is very welcome, just wish a few others would do the same. Sometimes I find forums very slow, perhaps we’ll get a few more looking in over the weekend.
I want to get started on my next PCB this will be the top board with an LCD module and driver, so then it can tell me what it’s doing or going to do, perhaps would be better!!
As for the wheel encoders, perhaps it will just be rev counting, for speed or stalling, etc.
Thanks for looking, did you know that the Picaxe 08’s and 14’s also use the same top 4 pins in the same way? so you can in fact put an 8 or 14 pin picaxe in a 20 pin socket, it will get power and serial programming just the same, just ignore the empty sockets. I used this when I made my first stand-alone programmer. As you say with the Picaxe20M2 both ports are in line, so it’s so easy to bring them out in straight lines to headers, etc. unlike the Picaxe 28x Shield and the Arduino? where there all over the place…
The chassis is the Pololu RP-5 without encoders, now discontinued, but someone on ebay sells them from Germany There’s a good link here: http://www.mhobbies.com/new-c-control-robot-system-chassis-robby-rp5-rp6-robot.html if you take a look at this site you will see a gear with an hole in it, this I hope to use to check disance/speed or motor stall. Take a look here for others bots, etc. http://melsaunders.x10.bz I’ll upload a picture or two.
i didn’t know you can use a 08m2 and 14m2 in a 20m2’s socket, good info, thanks. you can make a optical encoder using infrared led and a phototransistor etc. such that there is a led on one side of that gear and phototransistor on the other side. So, it will give you a high pulse every time that hole passes in front of it
Yes I know about using a LED and photo-trany but I think the slotted opto switch saves all that messing around to get them in alignment, will perhaps fit with one srcew, etc, it will depend on the fitting? I might try and get around to making the LCD PCB this week, that could be fun, and then there’s the extra code to drive it.
It’s true as some folks say you’re a lot busier when your retiered than when you went to work 5 days a week… Lovely sunny day here in Leicester (UK) so been in the garden, planting stuff, then there’s my Cacti (about 300) to see too, just set up a make shift tank for some new fish, and then there’s Oscar my Corn snake… Will it ever end?? Then there’s my photography and model building.
Not done a lot with robots for some time, been in the Greenhouse with my 294 Cacti! But I have now managed to add another Shield PCB and an LCD display so now he can talk to me, via messages.
I am a bit disapointed with the Pololu RP-5 chassis, it’s very well made, but badly designed in that the wheels will still rotate even if the tracks are jamed and not moving. I could add more sensors, but don’t think this is the ideal really.
I may try their Zumo chassis or you can just buy the wheels and tracks, both of which have teeth so no track slippage?
Have you used either of these? your comments, and advice would be welcome. Here’s a couple of pictures…
Thanks for your comments, not done a lot with robots lately! been in the Greenhouse with my 294 Cacti tending them and had some super flowers.
But I have managed to add another shield PCB to carry an LCD so the bot can give me feedback in the form of messages…
I am a bit disapointed in the RP-5 chassis in that it’s well build but baddly disigned, the wheels will still rotate while the tracks are jammed, as there are no teeth between them. I think I may have a go with their Zumo chassis or you can just buy the wheels and tracks both of which have teeth. Have you used these? what do you think?
Who knows about current limiting? and how to make good use of it. ie. stop the motors when they stall!!
Well not been on the robot scene for sometime, too busy looking after my 294 Cacti & Succs, (Why did you think I was Cactusface). But I have now got another layer on my bot along with an LCD. So he? can reply and comunicate with me warn me if he gets a little too hat, due to hit something, etc.
Here’s a couple of pictures!?! but if it all bombs out like the last 2 times I tried, I’ll just give up…
Well not been on the robot scene for sometime, too busy looking after my 294 Cacti & Succs, (Why did you think I was Cactusface). But I have now got another layer on my bot along with an LCD. So he? can reply and comunicate with me warn me if he gets a little too hat, due to hit something, etc.
Here’s a couple of pictures!?! but if it all bombs out like the last 2 times I tried, I’ll just give up…
Regards
Mel.
PS Well, well what a suprise, it did’ent work!! I’m not going to waste any more time on this site or forum.
Nice to know you have added a LCD module on your bot I bet it looks even more awesome than before!
So now when you have added more awesomness to your bot, i think you should update this post. That way your post will come on the front page again and people will be able see your progress and the new features you have added to your buggy. If you don’t update this post, people won’t know you have done any progress. This is the reason why you are not getting any replies to your comments or any new feedback.
To update your post, first open it. Now at the top just below the heading “My new Buggy-Bot” you will see 2 tabs- ‘View’ and ‘Edit’. Go to the edit section and add you progress, videos, pictures etc. as you did in the starting while making this entry. If you are not able to add pictures (which unfortunately is not so straight forward here on LMR) have a look at this post- https://www.robotshop.com/letsmakerobots/node/22529 and this for adding youtube videos- https://www.robotshop.com/letsmakerobots/node/37586 i don’t know why the flickr link didn’t worked in your comments but you can post pictures through LMR also as described in the first link.
Just give it a go.
I wasn’t even aiming at it… really 
I bet it looks even more awesome than before!