After doing some searching the last few days I've found that either there is very little information on people who have created their own autonomous vacuum cleaners, or iRobot has done an amazing job at taking up a vast majority of searches on the subject every place I've found. Given the high cost of the Roomba, and the relative cheap-ness of robot parts, this is surprising to me. I've seen posts for the crumbot, and the post for the bot using that $7 mushroom vac from dealxtreme. So I'm wondering, is there any more information available?
The two scenarios I see for making this are either the vac mentioned above mounted to a robot, or going to Big Lots, finding a dirt-cheap vacuum cleaner, cut bits off, and build a robot around it. Having spent a week reading various things on this site I can say that I trust the group's intelligence much more than my own on this decision, and seeing all the help I got in my previous thread I figure this will be a good way to get ideas as to which direction I should go.
For the record I'm leaning towards the small vac a bit because I've come up with an idea that will give me a sort of PTO system for my robot. Basically there would be an adapter plate on the front which various accessories could mount to (ie: vacuum cleaner), and then build my own wiring harness (likely out of a molex connector or something) that would provide both power, and access to pins on the arduino (I'm pretty set on this board due to its ease of use) to be able to use sensors (ie: for a vacuum I'd want bump sensors on the front-mounted vacuum rather than on the front of the bot, so it would reach into corners). Or is this idea, like my last one, likely too crazy for an absolute beginner?
I love to see other endeavoring on robotic vacuums. I have been tinkering with mine for over a year (!) now. I went from those $5 USB ebay vacuums to a Magic Bug to a “mushroom vac” to a Black and Decker FHV1200. The B&D FHV1200 is a 12V cordless/bagless/washable filter model that seems made for a hack like this.
I found all the vacuums short of the B&D vacuum were only good when placed very close to the ground. Ok for hardwood and tile if the vacuum intake is close enough to the ground (read, very close). I gave up designing a floating intake nozzle that would adapte to changing terrain. Otherwise the vac rides too low to give enough underbody clearance.
The only problem with household vacuums is they aren’t shaped to do automated duties. I’m still stuck on how to detect/avoid obstacles with my new vacuum choice and its tall profile. There are also smaller 6V, 7.2V, and 9V cordless vacs out there but the reviews say they are underpowered as well. They might be easier to build a robot around if you removed the vacuum unit itself, I can’t say.
Yes, that vac is a bit more than the mushroom vac. I got it refurbished for $40 I think it was. A little much for a bot but currently I’m using it as a real, honest to goodness, handheld vac and it’s awesome except for the short battery life of the NiCads. I’ll work on that. Lipo’s to the rescue.
Anyhow, I believe it was ezekiel that was planning a major overhaul too. He aslo found the smaller vacs unsatisfying. I think he was fabricating something out of a ducted PSU fan that had some good pull. Haven’t seen him around recently however.
I can’t really say how doubling up on the smaller vacuums would work. In your case I might suggest a brush of somekind to assist in rooting up the debris. I found dragging the mushroom vac with its little bristles cleaned my low-pile rug much better that moving the vacuum over the bits passively.
If you stick with the small vacs you definitely should go with a debris chamber. Those little desk units just aren’t equipped for a household sized task.
My goal is similar as yours: Take a less-than-effiecient vacuum bot and throw lots of time at it to let it do a decent job. You might need a pretty hefty battery to acheive such a task without recharging. I don’t have much to offer as that goes. I was aiming at using AA’s and implementing a self-recharging ability but things have changed. Plus I was not aware that NiMH’s don’t like high discharge rates like vacuum motors tend to need.
that the Roomba has no where near the cleaning capability of something like the B&D you two are talking about. The impression I have gotten from articles/reviews is that it is maybe somewhat better that the mushroom vacs you speak of. Roomba’s aren’t good for a heavy job. They are meant to clean endlessly for hours that you are not around and pick up the small stuff of average days/lives.
As far as bump switches go, you may consider trying to use only 3 switches and then a solid ring that encapsulates the body. That way you will get 360* coverage with only 3 inputs.
The idea of using a simple ducted fan is a pretty cool one, but I’m wondering how much suction it would provide. Do you know if he ever did any tests with it? I’m thinking I may need to buy some styrofoam and do some experimenting with them if not. Even if I can’t make a decent home-made ducted fan that way, HobbyKing sells them for pretty cheap.
I had actually been thinking about using the bottom part of the mushroom vac that has the brushes on it, finding a way to mount it to a spinning head with a fixed suction tube going through the hole in the center. However I haven’t quite figured out how I would do that. I would like to have it on a bearing system, where the tube acts as the center hub and the base rotates around it, but I do not have access to equipment to fab such a bearing assembly. I’m also thinking that if I sacrificed a broom, I could drill holes in a helical pattern through a wooden dowl, thread bristles through the holes, and make a cheap home-made version of what most vacuum cleaners use.
I’m hoping with using a sauce-bottle debris chamber I can get it to do that cool cyclone thing that most bagless vacs do, purely so it would look cool (maybe some LED backlighting would make for cool vacuuming effects in the dark).
I’m actually also thinking about implementing some sort of self-recharging ability. The easiest idea I have come across in my research is to use an infrared LED at the charging station, and have the bot look for that LED. I figure that if I tell it to start looking for its recharge point with a decent amount of run-time left on the battery I can afford to let the bot wander around randomly until it finds it, and still give it a good chance of finding it before the battery dies.
Given that I am a complete beginner I know that many of these ideas will take quite a while ti implement even once I am able to start the project, but I’m very excited to begin, and again very happy to have such a great resource to turn to.
That’s the basic idea here, I will still vacuum weekly (or maybe even every other week) thoroughly, but having a vacuum run for 8 hours a day while I’m not home would at least make that job easier, and keep the carpets cleaner overall.
If I used a ring around the outside how would I tell what direction the bump came from? Is there a way that I could easily ensure some sort of accuracy on a rectangular bot?
Out of curiosity, where did you find them? I just looked on eBay and any of them that seem to be in working condition are still fairly expensive. I do still plan to do the DIY route, because I would like to learn and teach my girlfriend at the same time, so starting from scratch would be more educational for me.However if I can find an easy to fix roomba somewhere for $20 that would still be a cool thing to have.
If you have 3 switches equally spaced around a circumference, you will get reasonable notification about where the robot has been hit within a number of degrees of precision. If 2 switches are hit, then the bot has likely impacted near the center of said switches. I believe you can follow the logic along from here.
I see how this would work quite easily on a circular robot, as the three sensors could be equidistant apart, and you could easily read directionality of touch from that, however on a rectangular bot I don’t see how it would work. My base is a Tamiya track kit, and a Tamiya chassis kit, and in order to vacuum in corners (my house has a lot of them) I need the bot to be rectangular. I’m using 10mm momentary buttons as my touch sensors. Am I just an idiot and can’t picture this in my mind? I can’t picture a way to do it without front, left, right, and back sensors.
That pump is too slow for your needs. It only cranks out 12-15LPM. Standard vacuum cleaners pull anywhere from 100-300+CFM. A quick poke on the abacus says that pump puts out around 0.53 CFM. A little low
