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DreadLlama posted:I've got a 12V car battery on a solar panel, and also a "20V" (18V) li-ion battery. I want to charge the 20V battery using the 12V battery. I can use an inverter to run the 20V battery charger, but this seems inefficient. Is there a way to use a constant current (or constant voltage?) power supply and/or buck converter to charge a battery? Your question seems to boil down to "is there a simple way to charge a lithium ion battery safely?" The answer is, unfortunately, no. A constant voltage charging scheme will need a current limit, and constant current by itself is a straight no. You are probably best off eating the inefficiency of the inverter rather than designing your own smart charger.
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Jun 26, 2017 14:45
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KnifeWrench posted:Your question seems to boil down to "is there a simple way to charge a lithium ion battery safely?" The answer is, unfortunately, no. A constant voltage charging scheme will need a current limit, and constant current by itself is a straight no. You are probably best off eating the inefficiency of the inverter rather than designing your own smart charger. There is something kinda poetic about how mankind moved past the "giant tank of sulphuric acid" batteries to arrive at "small canisters of angry fire"
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Jun 26, 2017 14:48
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DreadLlama posted:I've got a 12V car battery on a solar panel, and also a "20V" (18V) li-ion battery. I want to charge the 20V battery using the 12V battery. I can use an inverter to run the 20V battery charger, but this seems inefficient. Is there a way to use a constant current (or constant voltage?) power supply and/or buck converter to charge a battery? A boost converter (as opposed to a buck converter) can output a village higher than the input. But you can't just charge a liion battery with that, you need a charger to do it safely. Your current charger may be able to run on 24v dc or similar but I don't think that is very likely. If you have a decent inverter and charger it might not actually be that inefficient.
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Jun 26, 2017 14:49
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ate all the Oreos posted:So my "scroll wheels in a box" project has evolved into trying to make a simpler, cheaper version of this overpriced bullshit:
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Jun 26, 2017 16:05
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ate all the Oreos posted:Anyway to start it's probably still going to be built into the same box, but I'm trying to come up with a protocol that will allow arbitrary nodes to be added later (probably just via a cable, not the fancy magnetic connectors these things have). What I've come up with so far is I2C, with a trimmed down version of SMBus's address resolution protocol (since I don't need most of the "device ID / vendor ID / etc" stuff). I don't think it needs to be hot-swappable or anything but I do want it to be able to set up the bus on its own without DIP switch fuckery. Am I on the right path or should I look into a different protocol? Remind me what the use case is again? I have a scroll wheel. I'm in some program and want it to actuate. I'm assuming on the software side you're wrapping it up inside a HID interface. So the main micro is speaking HID over USB, then the back end is talking to the wheels. The wheel encoder starts to move. How is it telling the main micro that something's happening? Dedicated interrupt line? I2C that's been polling this whole time in case something changed?
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Jun 26, 2017 16:54
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DreadLlama posted:I've got a 12V car battery on a solar panel, and also a "20V" (18V) li-ion battery. I want to charge the 20V battery using the 12V battery. I can use an inverter to run the 20V battery charger, but this seems inefficient. Is there a way to use a constant current (or constant voltage?) power supply and/or buck converter to charge a battery? For the car battery, get this 12v MPPT: http://www.ebay.com/itm/5A-MPPT-Sol...bUAAOSwj0NUdwZk I have two of this exact model and they've been working perfectly for months, just wire the solar panel and car battery to it. Then, I guess you can get this adjustable MPPT and turn the potentiometer so it puts out 20v under load: http://www.ebay.com/itm/Adjustable-...c4AAOSw32lYm98~ eBay has a lot of MPPT chargers (Maximum Power Point Tracking, aka they optimize solar panels to output the most amps at the precise voltage you want) under $10 that are well-suited for car battery or Li-Ion battery charging.
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Jun 26, 2017 18:18
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JawnV6 posted:Remind me what the use case is again? Controlling values in photoshop, basically JawnV6 posted:I have a scroll wheel. I'm in some program and want it to actuate. I'm assuming on the software side you're wrapping it up inside a HID interface. So the main micro is speaking HID over USB, then the back end is talking to the wheels. The wheel encoder starts to move. How is it telling the main micro that something's happening? Dedicated interrupt line? I2C that's been polling this whole time in case something changed? I haven't really figured that part out yet, I'm leaning towards polling. If I were to do an interrupt it would probably be a shared open-collector one that could be asserted and would trigger a poll or something like that. If none of this will work my backup plan was just SPI polling at much faster rates but then I'd need a pin for each *thing* and ehhhh... I think I'd have enough bandwidth for I2C polling though, at 400kbps and assuming each message is equivalent to 8 bytes including address and request/response (which is actually bigger than I think it will actually be) and there's 8 devices, I should be able to poll all 8 devices ~750 times per second. e: Weird idea I just came up with: SPI for actual data transfer, I2C to signal a virtual "slave select" to the devices. Is this real dumb? Shame Boy fucked around with this message at 18:44 on Jun 26, 2017 |
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Jun 26, 2017 18:39
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ate all the Oreos posted:I haven't really figured that part out yet, I'm leaning towards polling. If I were to do an interrupt it would probably be a shared open-collector one that could be asserted and would trigger a poll or something like that. If none of this will work my backup plan was just SPI polling at much faster rates but then I'd need a pin for each *thing* and ehhhh... If the general idea is "huge long user-pluggable wires" you don't get to bump up to the protocol limit speed  ate all the Oreos posted:e: Weird idea I just came up with: SPI for actual data transfer, I2C to signal a virtual "slave select" to the devices. Is this real dumb?
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Jun 26, 2017 19:46
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JawnV6 posted:I think a human UI is going to be noticeably slow if you're multiplexing polled I2C. You have 80ms to play around with before a human notices it's not "instant," good chunk of that is going to be lost on the PC interface. I haven't actually done this, but it's easy enough to virtually delay things to simulate the effect. Well they wouldn't be too long but yeah I get your point, hm. JawnV6 posted:Two micros, two protocols, needs to be 100% reliable or someone's going to short out MISO. It'd be so much simpler to wire up proper CS bits for each one, master HW just has to toggle a GPIO, micro just has to respond to SPI. That solution seems kinda racy, how big of a gap between the i2c tx finishing and expecting MISO controlled w/ legit data? Eh it was just a random thought I pulled out of my rear end, not an actual serious proposal  For additional context, originally I was just going to have some shift registers (with schmitt trigger inputs and debouncing RC filters) reading all the wheels directly, that would just get shifted out and read by the main (and in this case only) uC, and if I just can't get this working I'm going to fall back to that plan, but I really like the idea of stringing together as many controls as you need at one particular moment
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Jun 26, 2017 20:38
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ate all the Oreos posted:Controlling values in photoshop, basically Are you trying to chain them in user-configurable ways? If so, then why poll at all? Why not have each encoder have a little baby controller that watches it and reports any changes on the bus of your choice to the master microcontroller, which in turn emits the actual USB HID stuff according to its natural event loop? If not and it's just a fixed set of encoders, why not just buy a microcontroller with enough pins to watch them all? If you do have to poll for some reason, why not just have it be like a shift register, where each unit chains into the next, and reading is as simple as clocking in as if you're reading from a bunch of actual shift registers. You end up a with a really simple two or three wire interface.
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Jun 26, 2017 21:01
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Stabby McDamage posted:Are you trying to chain them in user-configurable ways? That would be ideal, but how exactly do I have 8+ different controllers talking on the same bus at once? I only went with polling because I couldn't figure out a particularly good solution for that... e: Wait I2C supports multiple masters doesn't it, derp Stabby McDamage posted:If not and it's just a fixed set of encoders, why not just buy a microcontroller with enough pins to watch them all? Yeah that was the first revision (well with shift registers instead of pins, but same diff). If I can't get the configurable one working I'm going to fall back to that I guess Stabby McDamage posted:If you do have to poll for some reason, why not just have it be like a shift register, where each unit chains into the next, and reading is as simple as clocking in as if you're reading from a bunch of actual shift registers. You end up a with a really simple two or three wire interface. That's a pretty good idea, thanks!
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Jun 26, 2017 22:18
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I'm bad at this. Trying to build a joule thief to light my keyboard (I have one of those desks with a smaller table above the main part for the monitors to sit on, and my laptop hands over and shadows the external keyboard), and ... welp. Mainly I don't have a ferrite donut. Can I use the inline inductors that look like resistors? Or wrap some wires around a nail? On the other hand, I finally finished out a much simpler project that I posted about before -- three of those Harbor Freight free worklights stuffed whole* into a flashlight that originally had a car taillight bulb and two 6v lantern batteries, powered by a USB phone battery. I call it "the sun." Well, I put the lens on, hot-glued the LED boards in place, and filled the rust holes in the case with epoxy (the latter worked out surprisingly well -- I put masking tape over the outside and painted the resin onto the inside of the tape). *The boards, I mean, obviously I took them out of their cases and hot-snot siamesed the PCBs together, but I just wired them in parallel to a common source, didn't have to gently caress with choosing resistors or anything. I still need to rejigger the wiring and strip the cable right near the plug inside the battery box so I can use the USB data wires with alligator clips for alternate power in an emergency -- last time the power went out, it was out long enough that the USB battery ran out, so I alligator-clipped a 4-AA holder onto the wires on the back of the LED panels (before I finished gluing it together) and ran through four sets or rechargeables and two sets of alkalines.) :"poo poo, power went out in the storm. Which flashlight you want? gently caress, where is a flashlight? I found one, but it's low on batteries." :"Nah, we cool, I got the sun." [flip switch, reenact Genesis 1:3] "loving gently caress of a gently caress, why did I look at it when I turned it on?!"Once the sun goes down I'll take some pictures of it. Seriously, it's damned near as bright as the CFL in the ceiling fixture, just more focused. Also, alligator leads are a drat godsend -- I have car chargers for our phones, but the cigar lighter socket in the car only works with the key on, so during the recent power outage I just clipped the charger nubbins directly to the car battery (after using the last of my phone's battery to Google the pinout, because I never remember) and set the phone being charged on the intake manifold and closed the hood. Chillbro Baggins fucked around with this message at 01:16 on Jun 27, 2017 |
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Jun 27, 2017 01:11
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Bad Angus! Bad!
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ate all the Oreos posted:That's a pretty good idea, thanks! Thinking about the protocol, you could do the inverse of what those addressable LEDs do. On the LEDs, you send out a string that's {x}{c0,c1,c2,c3,....cx}. Each LED subtracts 1 from x, sets its color to c0, and sends everything else on. So your little dealies read in a byte from one direction, then that many bytes, add one to the first byte, spit it out, spit out everything else, then spit out their data. So your first dealie knows the bus is terminated, so it spits out 1x. The second one up the chain reads the 1, then 1 byte, and spits out 2xy, the third would be 3xyz, etc. Your micro now knows how many things to expect.
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Jun 27, 2017 02:20
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Protocols that pluck a byte off the wire to determine how many more bytes to pluck off smell funny to me. Each encoder is sending a signed byte of how many ticks have happened CW/CCW since the last sample?
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Jun 27, 2017 03:04
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babyeatingpsychopath posted:Thinking about the protocol, you could do the inverse of what those addressable LEDs do. Yup, that's what I was trying to describe as "like a shift register". JawnV6 posted:Protocols that pluck a byte off the wire to determine how many more bytes to pluck off smell funny to me. I'm thinking each encoder+controller stores the a "current" value as a byte, and just sends that along. The master can always subtract the last metric from this one to get the change, which works even if there's an overflow. This is how a lot of monitoring systems work: just send a counter and let the receiver compute the delta over whatever time window they want.
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Jun 27, 2017 14:45
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Zero VGS posted:For the car battery, get this 12v MPPT: http://www.ebay.com/itm/5A-MPPT-Sol...bUAAOSwj0NUdwZk I like things that are cheap and your MPPT qualifies. But I have seen some youtube videos accusing them of being too-good-to-be-true. https://www.youtube.com/watch?v=la-gvy0DfJs (tl;dr: they use cheap mimicry to emulate MPPT but don't actually do anything). One way to quickly guage whether an MPPT is genuine or not is whether it's got an inductor in it. Have you ever had it apart? DreadLlama fucked around with this message at 20:17 on Jun 27, 2017 |
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Jun 27, 2017 20:14
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DreadLlama posted:I like things that are cheap and your MPPT qualifies. But I have seen some youtube videos accusing them of being too-good-to-be-true. https://www.youtube.com/watch?v=la-gvy0DfJs (tl;dr: they use cheap mimicry to emulate MPPT but don't actually do anything). I opened mine up, the first one I linked, and it had heatsinked mosfets but I don't recall if there was an inductor, I'd have to check again. In any event it certainly works to keep the car charged, I've been using the radio and interior lights for a month now and everything is fine, and the charge level LEDs work since my battery was near dead when I installed the solar panel and MPPT, and now the interior lights come on strong and the MPPT reflects that. I can take a multimeter to it later... if the MPPT isn't bucking down to 14.4 or whatever charging voltage, that would mean it's feeding the straight 16-18v into the lead acid battery which I assume is pretty bad?
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Jun 27, 2017 21:00
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Mosfets are required for PWM. Missing MPPT would be indicated by lack of increased amperage. MPPT implies transformation according to P=IV. PWM lowers voltage by using mosfets to chop up relatively high voltage at high frequency. The voltage stays the same but is cycled on-off. If a 20v source were cycled such that out of every second, it were on for only 0.6seconds, it would be as-good-as 12V as far as most any load could be concerned. MPPT works via magic wherein it transforms DC current somehow. DreadLlama fucked around with this message at 04:21 on Jun 28, 2017 |
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Jun 28, 2017 04:15
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I have a small 12v DC pump that I want to run off a car battery, and keep the car battery topped up with a solar panel. I have the battery connected to the pump with battery clips and thats working fine. Can I use a second set of clips to attach a solar panel straight to the battery? I believe this solar panel has a regulator in it already.
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Jun 29, 2017 06:41
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Does the solar panel output 12 volts, and does it have a diode to prevent the battery from driving it backwards? If so then yeah, you can, but it won't charge the battery fast enough to stop it from discharging if the pump is running 24/7, so keep that in mind.
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Jun 29, 2017 08:06
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Sagebrush posted:Does the solar panel output 12 volts, and does it have a diode to prevent the battery from driving it backwards? Yeah, 6w at 12v. Not too sure on the diode, is there a way I can check? It's a tiny pump that pulls 6w Max, so it should last a while. Going to see how long it lasts and how many more panels I will need to sustain it.
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Jun 29, 2017 10:54
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NPR Journalizard posted:Yeah, 6w at 12v. Not too sure on the diode, is there a way I can check? A single one of these panels taped to the hood will run that pump 24/7 even with a stretch of cloudy weather: https://www.amazon.com/gp/aw/d/B013E07FNM/ Edit: and GreeSonic makes an MPPT which they go through great lengths to explain is a real MPPT and not a fake PWM type... I'm inclined to believe them because the 50w panel they sold me actually puts out 55w under load according to my multimeter: https://www.amazon.com/gp/aw/d/B071QXGV1Y/ Zero VGS fucked around with this message at 15:16 on Jun 29, 2017 |
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Jun 29, 2017 15:13
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What is the best soldering iron tip for SMT soldering with a Hakko FX-888D? I wanted to get the kind with a hole for a solder well but people seem to be trying to make it as hard as possible to get these kind of tips in Canada; apparently there's some kind of patent issue preventing the official tips from being sold in North America and very few people stock the one brand that is allowed to be sold here, and everywhere I've found doesn't ship to Canada, doesn't list it on the Canadian version of the site, or want ridiculous shipping costs to send something that fits in an envelope.
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Jun 29, 2017 23:52
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BattleMaster posted:What is the best soldering iron tip for SMT soldering with a Hakko FX-888D? I wanted to get the kind with a hole for a solder well but people seem to be trying to make it as hard as possible to get these kind of tips in Canada; apparently there's some kind of patent issue preventing the official tips from being sold in North America and very few people stock the one brand that is allowed to be sold here, and everywhere I've found doesn't ship to Canada, doesn't list it on the Canadian version of the site, or want ridiculous shipping costs to send something that fits in an envelope. I'm not sure if there's chinese ripoffs of it but I bought what I thought would be garbage tips off amazon (like a set of 10 for $4.99 I think) and they work as well as the real ones, to the point that I've mixed them up and can't remember which is which, so maybe you can get "unofficial" versions of it from less scrupulous vendors? e: Actually can you link the vendor you've found that actually sells it in north america because I'm not quite sure what you're talking about and it sounds neat Shame Boy fucked around with this message at 02:09 on Jun 30, 2017 |
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Jun 30, 2017 02:06
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Dave showed off SMT drag and dab soldering using one of these kinds of tips and it looked pretty easy. They have a hole that solder sits in and flows out of onto the pads. https://www.youtube.com/watch?v=hoLf8gvvXXU As far as I can tell the ones that are sold in North America that are compatible with the Hakko FX-888 are the Plato HS-0530 and HS-0531. I assume they're made by the company that has the North American patent on that kind of tip. Digikey lists them but doesn't stock them, Mouser has them but wants $20 for shipping, and sellers I've found on eBay and Amazon don't ship to Canada. I'm thinking of maybe just putting in a big enough order from Mouser to get free shipping but right now I don't need anything else in particular that I can't just get locally. The official Hakko tips are described here on their website along with instructions for drag soldering, but I haven't been able to find anyone selling them even for crazy prices. At this point I'd be happy with recommendations for whatever the next best type of tip is as long as I can actually get my hands on them. edit: or hell is there any downside to getting the tip that comes in the same shape minus the hole and drilling a small hole in it? BattleMaster fucked around with this message at 03:04 on Jun 30, 2017 |
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Jun 30, 2017 02:59
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BattleMaster posted:edit: or hell is there any downside to getting the tip that comes in the same shape minus the hole and drilling a small hole in it? Yes; most soldering iron tips have a copper core for better heat transfer, but since copper dissolves in molten solder they are then plated with iron and sometimes other layers of different materials for protection. If you've ever used a cheap soldering iron (with associated cheap tips and thin plating layer) the tips eventually wear down to the copper in one spot and then the tip seems to dissolve from the inside out. It's interesting that the Wikipedia article on soldering irons mentions the concave tip patent issue that you are running into. I had no idea this was even a thing.
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Jun 30, 2017 03:28
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It takes a little while for the copper to dissolve out however, if you don't need it for long (or don't mind doing it over and over) it's probably fine to drill a hole in a cheap lovely one and then just throw it out when it dissolves
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Jun 30, 2017 03:58
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Is there an easy home way to plate copper with iron  Alternatively if I can't get my hands on such a tip what's the next best tip and technique for SMT soldering?
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Jun 30, 2017 04:15
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BattleMaster posted:Dave showed off SMT drag and dab soldering using one of these kinds of tips and it looked pretty easy. They have a hole that solder sits in and flows out of onto the pads. Yeah I don't know about EEVblog but this dude has a some quality videos showing how to SMD solder: https://www.youtube.com/watch?v=wUyetZ5RtPs He, CuriousInventor, has a whole series of SMD soldering videos worth watching. Yeah, don't do this: https://www.youtube.com/watch?v=IpkkfK937mU
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Jun 30, 2017 05:30
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It depends. 0805s, a regular small chisel tip works great. A very small pointed tip works on some packages, a small chisel works on others. Buy an assortment and go to town!
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Jun 30, 2017 05:31
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DreadLlama posted:Mosfets are required for PWM. Missing MPPT would be indicated by lack of increased amperage. MPPT implies transformation according to P=IV. PWM lowers voltage by using mosfets to chop up relatively high voltage at high frequency. The voltage stays the same but is cycled on-off. If a 20v source were cycled such that out of every second, it were on for only 0.6seconds, it would be as-good-as 12V as far as most any load could be concerned. it's not quite magic in fact it's basically a standard PWM controller with additional voltage and current sensing circuitry along with the software to track the actual power delivered over the duty cycle variations instead of bog standard dc/dc pwm conversion where it's a fixed ratio based on the input and output voltages. in more spendy variations you will get the boost circuitry as well to deliver a tiny amount of charging power when the panel voltage is below the load voltage but because of the small amount of power a panel can output at those voltages and the losses associated with the boost stage it's almost not worth it, so a lot of the time you just end up with a buck converter with a smarter brain. not to say those chineseium specials are actually doing MPPT, but it's less complicated than you would initially think. that being said I've seen a lot of expensive units that actually do MPPT then go ahead and throw away half the advantage by doing stupid poo poo like quiescent current of 5 milliamps all the time and multiple diode drops in the current path. there are also considerations like does the synchronous control leave the low side swich on all the time charging the input filter caps wasting energy as heat or do they actually switch off when the current hits zero and suffer a nosier output needing more filtering, this is the real complicated poo poo but it's more general to DC power supply design instead of the MPPT specifics Dairy Days fucked around with this message at 17:03 on Jul 1, 2017 |
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Jul 1, 2017 16:56
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BattleMaster posted:Alternatively if I can't get my hands on such a tip what's the next best tip and technique for SMT soldering? My lazy way of doing low-volume SMT stuff with a standard chisel tip is: 1) Melt a bit of solder onto one of the corner PCB pads 2) Pick up the chip with a tweezers and align it into place with one hand while keeping the corner solder blob molten with the other hand. The goal here is to get the chip square and flat on the PCB. 3) Tack down the opposing corner with more solder to make the chip mechanically stable 4) Do a kind of drag solder technique along all of the rest of the pins, but don't worry too much if you get bridges between pins 5) Lay a bit of narrow solder wick along one row of pins and drag your iron along the top of it. It should suck up any gross blobs/bridges while leaving the tight pin-to-pad interface alone. Do the same to the other row of pins. 6) Clean up flux with a q-tip and acetone or whatever solvent works for you Also, always use a magnifier for SMT if you can. Something in the 2x - 5x range is usually good. The key thing here is to get the chip square and flat and then just gob on solder like an oaf. The solder wick is amazingly good at removing the excess solder you don't want, leaving a light tin layer on the copper with a small fillet around the base of the pins.
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Jul 2, 2017 02:31
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It was suggest I post my audio problem here, so here goes! Pioneer SA 520 amp Working perfectly before I left home. Someone apparently moved the cupboard it was on (there's a tapedeck and turntable on top of it) when it was powered off like a foot, and now nothing comes out of the speakers. I've tried two different sets of speakers and cables. I've swapped all the cables around. There's sound coming from the cassette deck as indicated by the level display, but there's nothing on the level display on the amp. No sound from the turntable either. Switches on fine, no explosions or noises. Haven't been able to test out the headphone jack as I don't have the right size thingie. I opened it up and I think it looks fine? http://imgur.com/a/Ocv1Q Tried the tape deck with a different amp and speakers and works fine. Any thoughts? Would replacing the fuses help?
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Jul 4, 2017 02:21
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ate all the Oreos posted:There is something kinda poetic about how mankind moved past the "giant tank of sulphuric acid" batteries to arrive at "small canisters of angry fire" The electrical engineer at work gets angry at me for calling lithium ion batteries "harnessed explosions" Things powered by harnessed explosions sounds way cooler than powered by lithium ion.
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Jul 4, 2017 05:37
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Fuckface the Hedgehog posted:The electrical engineer at work gets angry at me for calling lithium ion batteries "harnessed explosions" I feel like this would be pithier and less confusing if internal combustion weren't a thing
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Jul 4, 2017 07:36
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Zero VGS posted:That looks awesome, so I went and got one on eBay, $58 shipped from New Jersey and includes the proper barrel connector: Just wanted to say, I received the power bank today, this and the soldering iron together is the loving greatest thing ever. I popped eight 18650's from an old laptop battery into the power bank, set it to 24v output, and by luck the output port on the power bank is the exact same as the cable the soldering iron comes with, so it was plug-and-play. Heats the soldering iron up like 3 seconds flat (max amp pull was 2.8), and the bank's OLED display tells you how many amps the soldering iron is pulling. The soldering iron has a built-in accelerometer so when you set it on the table it lowers the temp to save power until you pick it back up. So yeah, if you're serious about soldering get those two listings and some 18650 cells and you'll have a portable soldering station that'll last for hours. I think I'm gonna start soldering outside where everything is well-lit and there's no fumes!
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Jul 6, 2017 04:09
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So I've never worked with motors. My arduino knowledge has mostly been lights/sound. I'm working on the ZF-1 gun from the Fifth Element.  https://www.youtube.com/watch?v=7jVsQToSfag There are a few hatches and things that I'd like to engineer into actually opening or extending, controllable via arduino. First impulse was to look up "linear actuator", only to discover that that poo poo is expensive, probably because most of them are load bearing. What's the cheapest way to do something like extend a barrel here? Something with a regular motor and a rail with teeth?  Is there an easier answer I'm missing?
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Jul 7, 2017 02:29
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Harvey Baldman posted:What's the cheapest way to do something like extend a barrel here? Something with a regular motor and a rail with teeth? Idk what options you have for hooking a stepper motor up to it, but that thing you drew is a "rack and pinion".
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Jul 7, 2017 02:33
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JawnV6 posted:Idk what options you have for hooking a stepper motor up to it, but that thing you drew is a "rack and pinion". Words! Thank you.
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Jul 7, 2017 02:59
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Harvey Baldman posted:So I've never worked with motors. My arduino knowledge has mostly been lights/sound. You could also do something with threaded rod -- you either spin the rod and a non-rotating nut rides it, or spin a nut and the non-rotating rod moves down it. Not sure what your budget looks like, but there's also pneumatics. You'd either need to fill an air tank externally and have a fixed number of actuations, or include a compressor in your model. You'd actuate with a solenoid valve. If you don't need much travel, you could look at coupling a servo to something on a linear bearing.  If you *really* don't need much travel (~1/2"), you could look at just solenoids.
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Jul 7, 2017 03:01
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