Revisiting the original Roomba and its simple architecture
robotsinplainenglish.com
robotsinplainenglish.com
In the pandemic I bought the cheapest one, and it worked very well. It had a handle so I could pick it up, responsive buttons, and intuitive tones.
A few years later I bought one that automatically suctioned debris into a home base. That one had no handle, required reset frequently, and had tones that made you guess which Japanese train station it just arrived at.
Something went wrong at that company, and I don't think competition is an excuse.
Back in the day (about 2002) I was working at an education software company which was trying to get itself acquired by Microsoft. MSFT came in and told us our software didn't conform to all these "standards" in the educational software space. Standards which, coincidentally, Microsoft themselves had written. These pseudo-standards did absolutely nothing to help our customers, and were pure bureaucracy and very very complicated to implement.
I'd recently read Charles Ferguson's book about how his company was acquired by MSFT, and recognized this part of their standard operating procedure, along with extreme and invasive due diligence where they spend a lot of time working out if you're stupid/pliable enough to jump through these hoops while buying themselves time to work out if they can clone your product. I tried to warn management (yes, really - even bought them copies of the book) but naturally no one would listen, and reading a book was too much like hard work. At some point MSFT simply ceased returning management's calls, and rolled out a similar product a while later.
The company imploded not long after, not for this reason in particular, but it was part of a general pattern of incompetence and mismanagement.
I had over a ~10 year period purchased 3 roombas. Generally I purchased in the upper half of current product range at each purchase time.
The most reliable, problem-free, longest lasting Roomba was the first initially purchased one. Every new one with more sensors/cameras/features worked worse. Cleaned worse, got stuck more often, was less easily fixed when in a bad state, etc. They got so bad I just stopped using them all together about a year ago.
Every time I purchased a newer Dyson cordless by comparison, the product seemed better than the last generation.
Is it my best vacuum if I'm comparing vacuums on technical specs? Hell no.
Is it my best vacuum if I'm comparing by time used? Absolutely.
The bump sensor, cliff detection, and wall detection were all implemented with plain IR LED emitter/receiver pairs, and very carefully shaped plastic enclosures so that the sensors provided a binary signal (floor vs. cliff, wall present/absent, etc.) that would hold up for the millions of cycles the machines racked up. This 'filtering in the sensor' simplified the inputs to the 8 bit 8051 microcontroller, and lowered the cost to a couple of cents for each detector.
The cleaning head used the torque of the brush motor to actively control the height of the cleaning head as the machine moved from carpet to hard floors and back. That's the 'core trick' that let the Roomba clean well on multiple surfaces with about 15 watts of brush power. Details in the now-expired patent -- https://patents.google.com/patent/US6883201B2/en.
Dave Nugent came up with the original torque lift idea, and then we worked it into the 'floating pulley' approach used in the final design. It seems obvious now, but at the time this was a radically different approach to mobile cleaning. Everyone else (Electrolux, Karcher, etc.) tried to make a miniature vacuum, but that burned too much power for a mobile system.
Joe Jones (project originator and team physicist) wrote a book about the original team and our development process that I recommend: https://dancingwithroomba.com/
Minor tech notes: Phil Mass did the original programming on the first generation Roomba in C on the aforementioned Winbond 8051 microcontroller. I think it had 256 bytes (!!!) of RAM and 4K of ROM.
The code was burned into the chip at its creation (no onboard flash!) so it had to be right the first time. For the 2nd generation system they ported the behavior code to the internal LISP dialect in use at iRobot.
It was a wild ride. I'm both proud of what we did, and dismayed (but not surprised) at what happened afterwards.
Not long after that is when I started reading hardware hacking stuff. The early Roombas were extremely hackable - each one had a serial port connector under a cover and you could connect it to a computer and drive them around. It was the pre-Raspberry Pi days; I remember people attaching a router or the lightest netbook they could find for some sort of wifi remote control.
I was too young to ever get to play with one, but I did get to take a broken one apart once. Some highlights were the planetary gearbox contained inside the wheel hubs, and a cam on the rear caster which would trigger an optical limit switch once per rotation so it could estimate distance traveled.
It's easy to agree with the article here that the off-the-shelf simplicity of the early Roomba was a virtue. I appreciated that sense that you could look at a lot of the parts and guess what they were for or how the operated from the software side. That caster was one of those for "oh, yeah, that's probably for simple distance estimations".
Software is certainly easier to replicate that hardware, 1M copies cost almost exactly the same as 1 copy :)
It's a vacuum + mop combo which imo is way better for hard floors
As a bonus, there are open source drop in replacements for the mfg's cloud service so you can self host your floor maps and stats, if that's your jam. (this isn't roborock exclusive though).
It's not valetudo is it?
My experience with HN is people generally prefer to dog pile onto whatever was mentioned, say it is the worst option, then bicker with each other about all the solutions being proposed. I say bicker, but those threads can be great sources of info.
Reddit is a weird place that is not real life.
i have never seen an HN thread about Reddit that didn’t turn into mostly hating Reddit.
Robots without cameras have an extremely difficult time distinguishing obstacles like cables etc on the ground.
And yes, I keep the floors free of cables and clutter when it's vacuuming time. That isn't a hassle
It still saves me time, which was the reason that I bought it in the first place.
https://www.technologyreview.com/2022/12/19/1065306/roomba-i...
It’s incredibly difficult in a successful business to change direction or even innovate.
There’s a bunch of guys in the engine room throwing coal into the furnace.
There might be one or two lookouts shouting - but they are drowned out by the noise of the engines.
If you’re lucky there’s a guy in the wheelhouse desperately spinning the wheel - but the connection between the wheel and the rudder is broken.
Reminds me of this one car company that sold me something called "FSD" that never worked. Hopefully they'll be bankrupt soon too.
You should look at a teardown of one of those sensors. It's a 1D lidar (if you can even call it that, until recently all of those were not ToF but more triangulation/reflection angle) being spun, no high res scans of anything can be achieved using that tech :)
I wonder if they fell into a sunk cost fallacy with their camera-based approach.
Right now, their chinese OEM bought them and seems to be committed to keeping their robovacs alive.
It is my understanding that US availability of the top models (such as 705 combo) may be limited, so here is a german youtube channel that has a lot of reviews of their newer units and compares them to the old ones (usually the S9 or 980, as those are the best units when it comes to vacuuming): https://www.youtube.com/@frickhelm/videos
I have also recently set-up the LIDAR-equipped 705 for my parents and let me tell you, there is no comparison.
The navigation speed is greatly improved which means cleaning tasks take a lot less time. Furthermore, it works in complete darkness with no problems! The camera-equipped model just bumps into stuff randomly and then gives up when it's too dark.
I can’t help but wonder how well a token-based AI could iteratively tune (or develop) a subsumption-based AI.
The day after Christmas I was front-page of Digg, Gizmodo, and Slashdot at the same time :-)
Unless you're a massive operation, you're probably just using an existing academic project, many of which handle a variety of inputs (depth, 2D lidar, 3D lidar etc), ie RTABMAP (what I started with), ORB-SLAM, nVidia Issac ROS SLAM (if you're on Jetson) etc. AMCL is an old-school algorithm for localization with 2D data - I tried it by taking a fake 2D scan from the depth camera and it was pretty terrible, so currently I'm trying to get visual-only SLAM working well enough for me because I don't want to spend $1k on a decent 3D lidar.
thanks for the resources !. I've been trying to get a wide view by looking at different algorithms, but I was curious what was actually used in production systems especially for consumer products.
RTABMAP and Cartographer came up in my searches, will definitely give these a closer look to understand how they work.
Right now im starting off with filter based approaches like Particle filter and Kalman filter, but i'd also like to understand how the graph based approaches work.