I just went through my younger cousin's junk and found a pretty cool Hex Bug spider he wasn't using. Unfortunately, the controller for it is lost. I want to find a way to "hack" this Hex Bug using my Arduino UNO to make it autonomous. Preferably, I would like it without any external wires or parts sticking out, but if that's the only way to do it, then I'll do it.
Obviously, there is the issue that the UNO is too big for the hex bug. I've read about etching PCBs, the Arduino Pro Mini, and using the UNO as a programmer or something like that to load it onto an "ISP"? (I'm not too sure how that last one works, any explanation would be much appreciated.) I'm pretty sure I don't have the tools or expertise to etch a PCB, so my options are just buying a Pro Mini, or loading it onto an ISP.
Second, there is my complete lack of knowledge on how the bug itself works. I've learned that it walks using what is known as the "Jamius walking mechanism", but I haven't found any resources about how the mechanism actually works. (Once again, any explanation would be much appreciated.)
So - to sum things up: I need some suggestions on how to tackle this problem, some guidance on how to do it, and the mechanisms behind the bug itself. I have a pretty good understanding of C and C++, but my knowledge of hardware and general electronics is close to none. So, please keep the technical jargon to as much of a minimum as possible. Thanks everyone for your time and effort in assisting me!
wherewolfe:
Obviously, there is the issue that the UNO is too big for the hex bug. I've read about etching PCBs, the Arduino Pro Mini, and using the UNO as a programmer or something like that to load it onto an "ISP"? (I'm not too sure how that last one works, any explanation would be much appreciated.) I'm pretty sure I don't have the tools or expertise to etch a PCB, so my options are just buying a Pro Mini, or loading it onto an ISP.
You don't load anything "on" an "ISP". "ISP" stands for "In-circuit Serial Programmer" - it's essentially a device to allow you to program a microcontroller without a bootloader. If you look on an Arduino UNO, you'll see pins labeled "ICSP" - which are what you connect the "ISP" to (yeah - it's a bit confusing; I am not sure why for the programmer they drop the "C", but for the header it is there). In fact, this is how you get a bootloader onto a bare ATMega328 (or other microcontroller); you don't need a bootloader to load the binary the compiler creates; the bootloader is just there so that things are easier (on the Arduino). There is also a sketch you can load onto an Arduino that will allow you to use it as an "ISP" (instead of buying one).
That said - you could just stick with a Nano, with the bootloader on it (though I can't remember off the top of my head whether you need a separate USB to serial cable or other dongle on the Nano to program it).
wherewolfe:
Second, there is my complete lack of knowledge on how the bug itself works. I've learned that it walks using what is known as the "Jamius walking mechanism", but I haven't found any resources about how the mechanism actually works. (Once again, any explanation would be much appreciated.)
Well - there are two motors in the mechanism - one controls the walking of the legs, the other controls the direction the legs "walk".
What you are looking for can be found here, by the inventor:
Let me tell you something though - this guy is very smart (and obviously somewhat wealthy). But he also seems to evidence some kind of mental health issues; this is very apparent if you watch his videos. He is likely good with his medications, though - to me it seems like some kind of OCD, or bipolarism, or something of that nature. He seems to have it under control, but at the same time some of those videos seem kinda disturbing to me. I mean, ordinary people don't generally "chuck it all" and then go out, buy a patch of property on a mountainside that you can only get to by hiking, build a "house" out of "junk" (but I have to give props to him actually doing it - that takes a lot of talent and hard work!), which can only be brought in by walking it in, all with the purpose of finishing building a giant sized version of the "walking spider". I really think he'll get it done, he definitely has talent, and drive - but I don't think the drive portion comes from a great place in his mind, unfortunately. He has the mind of a genius artist mad scientist kind of character, and I wish him luck with his projects and ideas; I just hope his self-imposed bohemian out-in-the-woods lifestyle don't lead to a breakdown or anything. And I can't be the only one thinking this, either - he seems to have plenty of friends he spends time with, which is a good thing. I have a friend who at one time acted just like Jamie - tons of energy, then low spots, then tons of energy, etc - he was a mad genius programmer, now he's burned out, living with his mom, and trying to figure out his place in life (and he doesn't seem to get out of the house much, or want in the way of visitors - so not much like Jamie in that regard).
So - I measured the board inside the Hex bug, and unfortunately the board is really tiny - no bigger than a quarter. So, the Nano would actually be too big. In fact the Arduino Pro mini would also be twice the size and would not fit into the hex bug. It seems that using the Arduino as an ICSP (or ISP) is my best option. Could you explain more how I would do that? I know more or less that I can load a program onto a bare microcontroller thing, but how would I run that program without a breadboard? (Sorry if I'm being too vague here) In other words, once I load a sketch from the Arduino onto a separate microcontroller using a breadboard, do I NEED to etch a PCB and solder it on to run the sketch on a smaller board?
"Inside there's a double sided PCB with a 14 pin MCU on one side and a dual H-bridge driver on the other. The other device is a combined red LED and IR receiver. It's a simple enough job to remove the MCU to get to the H-bridge inputs directly, then add sensors and patch on an MCU of your choice. "
I found this on Let's make robots, I thought it might be useful. Unfortunately, I don't know what an MCU is, or what this guy is talking about. If this is important, please let me know.
No one seems to have responded recently, so I guess I should elaborate more. As of now, I need a way to somehow etch a PCB and then use the arduino as an ICSP to program another microcontroller to put onto the PCB which I will put into the hex bug. I have no knowledge of how PCBs work and how to make them, and the resources I found don't seem to be helping much either. Once again, any help would be much appreciated.
I'm currently refining a hexbug hack which is pretty similar to what you want to do.
It runs on a custom PCB (that I specifically designed to be home etched) and uses infrared to control the toy.
I'm still in the process of setting up a Wordpress site with info, so code and PCB etch plans will be uploaded soon - but if you like, you can check it out so long: http://fr-e.za.net
(This is my first post and I'm not sure if I'm allowed to post links, so please accept my apologies if this was not allowed.)
I can't assist much on the topic of how to make your own PCB though. There are many tutorials online that would do a much better job of explaining...
PS: An ISP programmer can easily be built on a breadboard. There is a tutorial right here on arduino.cc
Go check it out. The PCB is very easy to etch and uses the absolute minimum of parts.
Should not take more than an afternoon to make if all goes smoothly...
Sorry for the late reply, I was looking into stuff as well for help. So, I decided against etching a PCB as it was too expensive and I didn't know how to do it. I just bought a PC board with pre drilled holes and I am now going to just solder wires across the boards to make a simple circuit. Now for some help with shopping I don't really know where to get many parts, so hopefully other people do. Here's what I need:
A dual H-bridge driver
Some sort of microcontroller with at least 14 pins
Some sort of cheap tiny rangefinder (I have no remote, so the goal is to make it autonomous)
I don't really know where to get many parts, so hopefully other people do. Here's what I need: