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The quest is simple. Make the SpotBot shut up.
I intended to document what was to be a simple hardware hack. I ultimately used a microcontroller to do this, but it could also be done by snipping a wire. I demonstrate 2 oblique ways to solving this problem which circumvent the need to completely disassemble the device in order to find the buzzer. The journey provides a glimpse into practical digital electronics and hardware hacking. And it could inspire you to break - err, fix - your own stuff one day.
I intended to document what was to be a simple hardware hack. I ultimately used a microcontroller to do this, but it could also be done by snipping a wire. I demonstrate 2 oblique ways to solving this problem which circumvent the need to completely disassemble the device in order to find the buzzer. The journey provides a glimpse into practical digital electronics and hardware hacking. And it could inspire you to break - err, fix - your own stuff one day.
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Signing UpStep 1What is a SpotBot?
What is a SpotBot?
The SpotBot is a carpet cleaning thingy. I don't receive any money for endorsing the SpotBot, but I endorse it, anyway. It's like a wet vac with rotating brushes for cleaning up stuff from your carpet. You just set it down over [motor oil, cat vomit, etc] and push a button.
There's something very satisfying about setting this thing on a stain, pressing the button, then simply going on with your life. But every SpotBot owner knows there's a dark side. When SpotBot is done doing your dirty work, it starts to beep. Loudly. Incessantly.
What's the big deal? Well, imagine you have a maid. You tell your maid to clean a spot on the carpet. Then you go about your business. You're relaxing in your recliner, sipping a marguerita, when your maid cries out, "All done! Come look and see what a great job I did."
You say, "Great! You're the best! Why don't you go home early, today?"
"No, come look! I did an amazing job!"
"Shut up, already."
"No, really! Come and see!"
Grrr.
"No, really! Come and see! I have my nose in the carpet and I can't smell any cat pee, at all!!"
"You're fired."
"You're so mean. You're a lousy client. I don't need you. I'll be going, now.... as soon as you come and see this!!!"
So you basically have to get up and tell the SpotBot "good job, now shut up" by pressing the stop button. I don't know who decided that a loud wet vac machine needed an even louder beep to tell you when it was done (you'd think the sound of silence would be good enough), but I'd like to give him my 2 cents on the matter.
The SpotBot is a carpet cleaning thingy. I don't receive any money for endorsing the SpotBot, but I endorse it, anyway. It's like a wet vac with rotating brushes for cleaning up stuff from your carpet. You just set it down over [motor oil, cat vomit, etc] and push a button.
There's something very satisfying about setting this thing on a stain, pressing the button, then simply going on with your life. But every SpotBot owner knows there's a dark side. When SpotBot is done doing your dirty work, it starts to beep. Loudly. Incessantly.
What's the big deal? Well, imagine you have a maid. You tell your maid to clean a spot on the carpet. Then you go about your business. You're relaxing in your recliner, sipping a marguerita, when your maid cries out, "All done! Come look and see what a great job I did."
You say, "Great! You're the best! Why don't you go home early, today?"
"No, come look! I did an amazing job!"
"Shut up, already."
"No, really! Come and see!"
Grrr.
"No, really! Come and see! I have my nose in the carpet and I can't smell any cat pee, at all!!"
"You're fired."
"You're so mean. You're a lousy client. I don't need you. I'll be going, now.... as soon as you come and see this!!!"
So you basically have to get up and tell the SpotBot "good job, now shut up" by pressing the stop button. I don't know who decided that a loud wet vac machine needed an even louder beep to tell you when it was done (you'd think the sound of silence would be good enough), but I'd like to give him my 2 cents on the matter.
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Thank you,
Jeff
The unit doesn't seem to do a good enough job of drying at least compared to using the wand manually. Looks like I can now wire it up to vacuum, spin, spray whenever I want with some toggle switches. It sure drinks the solution like a fish so hooked up to an external fill/drain tank this thing can actually be more useful than it already is.
So the "power pin - pre regulation" pin is the main voltage source for activating the other pins?
Ah, no. In case anyone else is tinkering with their Spot Bot, do not connect preregulated power to any of the other pins. To play it safe, connect a wire to the regulated 5 V line (after it exits the LM7805). and touch that to the various pins (avoiding the ground pin!) to play your Spot Bot like a puppet.
Also, those pins are connected to the microcontroller on the pcb. These are probably set to output low ( I never checked, maybe they're actually set as input?) and you're overriding them when you do this. So you probably shouldn't leave them on there for any long length of time, lest you damage your Spot Bot. Although I did this in the vid and caused no harm.
When I actually plugged in a micro with a custom cleaning routine, I diode isolated the header so I wasn't pushing a line while it was pulling.
Yeah, I noticed that, too. My current solution for both problems: I actually wrote up a custom cleaning cycle that doesn't spray, at all. It just vacuums and brushes, with a change of direction every 20 seconds, or so. Then it stops automatically after 5 min. (I guess the simpler hack would be to just snip the beep wire and the spray wire!?)
So instead of letting SpotBot hose down a big circular area several times per cycle, I use a spray bottle to put the cleaning solution only on the stain and let it soak in for a minute before setting SpotBot into attack mode. The results are good, the carpet stays drier, and the fill tank goes a long, long time (before filling with concentrated, opaque brown juice :)).
On the control board, there's a little 3 pin TO-92 transistor-looking thingy which is really a small 5V regulator. This feeds the board's microcontroller, and the microcontroller output controls the SpotBot. So technically, the circuit is designed to be run at 5V. But...
Like I said, I haven't seen the actual drive circuitry; I only have access to the control board side of it. But I'm guessing that the motors are all switched with a darlington array with built-in base resistors. Or N-FETs. In any case that I can imagine, there should be no worries using the unregulated DC.
There is ONE thing to be careful about. When the motors and other stuff are OFF, the microcontroller is actively sinking. So you do not want to have the control board actually plugged in when you decide to start filpping switches. This will short the microcontroller, unless you unplug or isolate it.
Now when I unplug the jumper manually I'm still expecting that evil beep.
please tell me the "Private Album Password"
I need that stupid beeping to stop. I can tell its finished just fine without the indicator beep.
I've disassembled things by dropping them off a 5-story roof, too. About as effective as the sledge hammer.