Brookstone Rover 2.0 SpyTank Teardown 64
An anonymous reader writes "Like the Roomba and other hackable consumer electronics, the Brookstone Rover 2.0 looks like a great value for hackers and robotics experimenters. Check out this teardown and another link within for lots of pics and info."
I'd urge anyone to look inside Roomba (Score:5, Interesting)
I really recommend anyone with roomba to take their screwdriver and open the thing.
Once you do and compare the inner workings to the device linked in the article, you really start to understand the concept of product design.
To recap the differences for those who don't own one:
Roomba design shows massive modularity. Every component inside is relatively easy-to-swap module.
It's very easy to fix if something breaks down when everything is attached with 2-3 screws max.
Modules have fixed connectors which just slot in. You won't end up in situation like: "ooh, this 4-pin connector looks like that one, did I connect it right?"(see the pics linked - power connector and speaker for example)
You could probably 3D print matching spare modules if you made drawings for one.
Parts of the rover, like motors and gears are supposed to be modular, yet they don't really look like that to me, maybe I'm just misreading the images.
To me, it looks like "Made in China" - medium cost build. There's some build quality, it's not made from the cheapest material available, but it's not for daily use. Well, it's supposed to be a toy..
In the Rover, wifi and camera modules are most likely USB yet they use different cabling, why?
For hackable toy, those should be replaceable easily. Roomba doesn't have USB for wifi or camera either, but then again, it's a vacuum cleaner!
It’s one of those toys that is relegated to the closet shortly after its first set of batteries die.
Something from the article I'd have to agree with.
Linux is slow? (Score:5, Interesting)
The system is probably running Linux. It takes a while to become ready after the power switch is turned on, which is typical of Linux. A smaller RTOS would likely come up much faster. The fact that the device requires networking, and streaming of sound and video also lends itself to a Linux system. Linux already includes much of the software to make everything work. The size of the RAM and Flash suggest a lean, but very workable Linux based system.
Emphasis mine. Really? I've found my Linux installs to be very fast booting - certainly faster than Windows machines. Also, according to your pics there is an 80MHz crystal on there - any modern day OS you threw on that loaded from some external storage cluster would take a while to load. However, I didn't see any SD Card, SSDs or other external media device with which to hold a larger OS which means it's all embedded in one of those IC chips you couldn't find any information on.
Having said that, there are version of Linux which can fit on a single floppy drive - about 1.2Megabytes - and in this case the OS has been burned into one of the ICs. Point here is that it may not even be Linux.
Re:Linux is slow? (Score:4, Interesting)
The S29GL032N [spansion.com] on the main system board is a 4 megabyte Spansion flash chip. Not luxurious; but well within the realm of a router-sized embedded linux(though it neither implies nor excludes a bunch of embedded OS options).
As for speed, Linux can be made to be quite snappy; but it wouldn't surprise me if enough of the lag is in starting up network-related stuff, along with whatever server program the device uses to allow the client to connect to it, that you wouldn't be able to readily distinguish between Linux, Vxworks, BSD or WinCE on speed alone: sure, an embedded OS booting from solid-state storage on known hardware should move like lighting; but then it has to bring up an external USB device, do the WPA dance, send a DHCP request and receive a reply, and then start up whatever server program the firmware guys threw together for the client to connect to. And then we don't actually know how often the client side of things actually polls the IP where it thinks the device is supposed to be, or whether the device sends out some sort of broadcast when it comes up, or what. Too many variables to even say how fast the OS comes up.
What baffles me is that the author of TFA is apparently geek enough to take a screwdriver to a $150 toy; but is making dumb guesses about OS type based on boot time even though he found a populated serial header, with RX and TX labelled, no less... C'mon, man, you can be pretty sure that the thing is 3.3v(based on the flash IC and lack of visible level converters, might be 5v or 5v-tolerant, highly unlikely to be RS-232), the pins are labelled for you, and it'll probably boot-spew something at you, why are you guessing based on boot time?