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[00:00:41] <anonnumberanon> my first issue though after I got that working is that I had failed to realize the PID computations had to be done in real-time
[00:02:27] <anonnumberanon> those were the times when I got hurt by the propellers a few times on my arm
[00:03:22] <z64555> heh
[00:04:06] <z64555> hm. If not in real-time, what did you think they had to be done in?
[00:04:36] <anonnumberanon> like sequentially, without regard to a time-step whatsoever
[00:04:45] <anonnumberanon> that is a think with computers
[00:04:50] <anonnumberanon> a thing*
[00:06:48] <anonnumberanon> But the reasoning behind the fact that just doing things as fast as possible without timing is that you don't take into account that an acceleration is intrinsincally time-based.
[00:07:26] <anonnumberanon> So the science of your accelerometer is "change in speed over time", and thus your computer interacting with it should also have regular timing, or else any of its analysis of what's coming from the accelerometer, will be flawed.
[00:08:08] <anonnumberanon> Oh, replace the above by gyro and accelerometer.
[00:08:22] <anonnumberanon> Not just accelerometer.
[01:11:39] <z64555> yep
[01:11:58] <z64555> Just because you aren't looking at a system doesn't mean it isn't running. :)
[01:23:22] <z64555> oh WOW.
[01:23:29] <z64555> Some of the people have a great sense of humor
[01:23:45] <z64555> There was an announcement on the TV about a new baby
[01:24:00] <z64555> Yes, the parents are quite proud of their baby girl
[01:24:14] <z64555> Scarlett Green
[09:30:24] <rue_house> maxim is making an interesting move
[09:30:56] <rue_house> arduinos and hobby servos
[09:31:21] <deshipu> link?
[09:32:06] <rue_house> http://app.ic.maximintegrated.com/e/er?utm_campaign=FY17_Q1_2016_JUL_INH-FactoryAutomation-AMER_EN&utm_medium=email&utm_source=Eloqua&s=248385305&lid=476&elqTrackId=645812043A1503E662D6114B705B50AA&elq=ad05e3068cd14ef981e3971f13b2b387&elqaid=774&elqat=1
[09:32:18] <rue_house> that was in a recent newsletter
[09:32:52] <rue_house> https://www.maximintegrated.com/en/design/reference-design-center/system-board/6251.html
[09:32:56] <rue_house> and how about that
[09:33:22] <deshipu> ah, new connector standard, we need them
[09:33:33] <rue_house> look at the bottom
[09:33:46] <rue_house> ~"replace pneumatic actuators with servos"
[09:34:10] <rue_house> the differences are astrounding, but its an interesting statement
[09:37:13] <deshipu> well, boldly go where all the men are already
[10:20:54] <z64555> don't we already have several hundred thousands of connector standards?
[10:21:44] <deshipu> z64555: right?
[10:26:18] <z64555> "Developers are encouraged to build upon and enhance the code base."
[10:26:19] <z64555> kek
[11:29:09] <z64555> I keep wanting to buy a lathe :(
[11:29:44] <SpeedEvil> It's not a proper lathe unless it has a bed ou can sleep on
[11:31:57] <z64555> heh, I'm not getting one that big
[11:34:06] <Snert_> evidently, a Grumman Andros robot can deliver/survive 1lb. of C4 explosive. With det cord.
[11:34:16] <Snert_> I wonder how they lit that det cord.
[11:34:48] <Snert_> had to have been an electric igniter of some sort I guess.
[11:35:28] <SpeedEvil> z64555:
https://www.youtube.com/watch?v=hA0SCw8s2cg
[11:39:38] <z64555> shame I can't watch that now :(
[11:40:24] <Snert_> he never fires up the lathe anyhow. He just jawbones about it
[11:41:20] <z64555> oh lol
[11:45:02] <z64555> hm, looks like rack and pinions are sold
[11:45:27] <z64555> and T channels
[11:50:41] <z64555> hm.
[11:50:51] <z64555> Could attach a pair of T-channels to a 4x4
[11:51:15] <z64555> and use a board of the same type of wood for the tool holder
[11:54:44] * z64555 smacks some sense into himself
[11:55:04] <z64555> no z64! You will not make a lathe from scratch today!
[13:28:51] <z64555> cool stuff:
https://en.wikipedia.org/wiki/Magnetic_bearing
[13:31:12] <z64555> Brushless in-runner motors have these built-in
[13:32:24] <z64555> translational forces on the axis are probably a pain, though
[13:32:53] <z64555> *axis of rotation
[13:41:19] <SpeedEvil> No, they don't
[13:41:32] <SpeedEvil> they have conventional ball bearings
[13:43:21] <z64555> interesting. I suppose they go with an even/odd number of poles on the rotor and stator?
[13:44:36] <z64555> I want to get my hands on one and take it apart
[13:45:23] <Snert_> they talked about a "backup bearing" for in case power fails to the magnetic bearing.
[13:45:41] <Snert_> and a hybrid case.
[13:48:21] <z64555> probably, _hopefully_ they mean a bushing that'll make contact with the shaft before it hits any of the magnetic bearing's poles
[13:49:31] <Snert_> they also spoke of static continual load carried by a normal bearing, and transient loads being handled by the magnetic bearing.
[13:49:51] <Snert_> so it's a wild world on that one.
[13:51:34] <z64555> k, so the put the ball bearing at the pivot and the magnetic bearing further down the shaft
[13:51:58] <z64555> magnetic bearing helps control wobble from spin-up and spin-down
[13:53:00] <z64555> which, is probably all that it does do, unless there's some non-contact between the axel and the ball bearing somewhere
[14:02:47] <Snert_> sounds beyong my budget.
[14:03:41] <Snert_> I just want some cool quality stuff. At about $100.00- $150.00 per motor.
[16:21:00] <ToAruShiroiNeko> hello
[16:21:38] <ToAruShiroiNeko> so I am working towards building a robot
[16:21:49] <ToAruShiroiNeko> I have a few basic mechanics questions
[16:24:39] <deshipu> it's all just pipes
[16:25:31] <ToAruShiroiNeko> what?
[16:41:53] <deshipu> the internet is just a set of pipes
[16:42:41] <robopal> are the pipes more important than the nodes?
[16:44:52] <deshipu> of course!
[16:55:04] <Snert> which came first? The pipe or the node?
[16:55:19] <Snert> I say the node
[17:35:38] <anonnumberanon> Your mom is a node.
[17:36:13] * anonnumberanon waits for someone to follow up with a pipe joke
[17:41:54] <z64555> something something Bill Clinton and the Alaskan Pipeline
[17:42:13] <z64555> ToAruShiroiNeko: jokes aside, what are your questions?
[17:43:29] <ToAruShiroiNeko> so I am slowly building a robot
[17:43:34] <ToAruShiroiNeko> its conceptual at the moment
[17:43:56] <ToAruShiroiNeko> I have an 8 wheeled Rocker-bogie suspension in mind
[17:44:12] <ToAruShiroiNeko> a bit like this
https://i.ytimg.com/vi/lKUC3dr9AGM/maxresdefault.jpg (not my construction or design)
[17:45:05] <ToAruShiroiNeko> z64555 I am trying to find wheels for my rpuspose
[17:46:05] <z64555> mkay, well the cheap way would be to use some lawnmower wheels
[17:46:29] <z64555> the more expensive way would be to go to a robotics shop/website and get essentially the same thing
[17:47:33] <ToAruShiroiNeko> I am unsure what would be the best way to attach them
[17:47:43] <z64555> oh
[17:47:46] <ToAruShiroiNeko> z64555 I dont know how much of it did you get
[17:48:02] <z64555> "I am trying to find wheels for my rpuspose"
[17:48:34] <ToAruShiroiNeko> so I am looking at various sites
[17:48:39] <ToAruShiroiNeko> ehtey have wheels with 5 holes
[17:49:22] <ToAruShiroiNeko> I mean in the rim
[17:49:24] <z64555> no hub? lame
[17:49:33] <ToAruShiroiNeko> http://d2ul0w83gls0j4.cloudfront.net/products/60/600/603385.jpg
[17:49:38] <ToAruShiroiNeko> hub?
[17:49:45] <ToAruShiroiNeko> I havent bought anything yet
[17:50:01] <z64555> the hub is what attaches into those holes
[17:50:06] <z64555> Ever hear of a hub cap?
[17:50:12] <ToAruShiroiNeko> okay thats what its called
[17:50:21] <ToAruShiroiNeko> I am new to mechanics of it
[17:50:45] <z64555> with cars, the brake disc is part of or otherwise attached directly to the hub
[17:50:53] <ToAruShiroiNeko> yeah
[17:50:55] <ToAruShiroiNeko> cars are complex
[17:51:00] <z64555> and then the hub attaches to the rim, and the rim to your tire
[17:51:11] <ToAruShiroiNeko> so each wheel will probably be around 95cm
[17:51:18] <anonnumberanon> make sure you do the rim pipe job correctly
[17:51:42] <z64555> notsure if joke
[17:51:47] <anonnumberanon> :)
[17:51:50] <anonnumberanon> lol
[17:52:00] <ToAruShiroiNeko> this is kind of why I have a vaigue quesiton here, since there ought to be some sort of best practice
[17:52:13] <ToAruShiroiNeko> the robot will probably drag 30-40kg including the load and battery etc
[17:52:23] <z64555> What are your motors
[17:52:28] <ToAruShiroiNeko> so the wheels should be able to carry 50kgs for good measure
[17:52:34] <ToAruShiroiNeko> I dont have motors yet
[17:52:52] <ToAruShiroiNeko> for the moment I am thinking this without motors, a dumb cart to see how well the suspension actually works at walk speed
[17:53:19] <ToAruShiroiNeko> Rocker-bogie is supposed to be for very very slow speeds
[17:53:35] <ToAruShiroiNeko> I want to see how well it performs in walk speed
[17:54:08] <ToAruShiroiNeko> for motos I am thinking of having 4 motors, one for each set of two
[17:54:16] <ToAruShiroiNeko> or two motos, one for each side
[17:54:39] <z64555> ok, so you'll need a chain or pulley to distribute the power between wheel pairs
[17:54:48] <ToAruShiroiNeko> and they carry the torque via gears and straps
[17:55:01] <z64555> s/pully/belt
[17:55:04] <ToAruShiroiNeko> yeah
[17:55:25] <ToAruShiroiNeko> the belts would go into the pully turning around at the attachment as in the picture
[17:55:56] <z64555> belts can slip, just so you are aware
[17:56:13] <z64555> If you need high-torque in your system, you may need to switch to chains
[17:56:28] <ToAruShiroiNeko> but thats an issue for later since first thing I need to do is order wheels which will take about a month to arrive
[17:56:38] <ToAruShiroiNeko> a gear system may work better than
[17:56:41] <ToAruShiroiNeko> *then
[17:56:49] <ToAruShiroiNeko> the ultimate goal for this thing to climb stairs
[17:56:50] <z64555> with that kind of suspension? probably not
[17:57:01] <ToAruShiroiNeko> hmm
[17:57:07] <ToAruShiroiNeko> I can also do one motor per wheel
[17:57:22] <ToAruShiroiNeko> I dont know which method would be better
[17:57:32] <z64555> that gives you the most flexibility from the software side of things
[17:57:44] <ToAruShiroiNeko> yeah
[17:57:45] <z64555> as you can control precisely the amount of power to each wheel
[17:58:09] <z64555> stick a voltmetere or ammeter in with each motor, and you can detect when it slips
[17:58:10] <ToAruShiroiNeko> I cant see any reason to contol the pairs individually at the moment though
[17:58:13] <z64555> or stalls
[17:58:29] <ToAruShiroiNeko> I think I would go for servo motors rather than step
[17:58:30] <z64555> well, you said it yourself, stairs
[17:59:52] <ToAruShiroiNeko> http://smath.info/wiki/GetFile.aspx?File=Climbing2.gif
[18:00:35] <z64555> since *when* have you ever seen perfectly shaped stairs like that? :D
[18:01:30] <z64555> also, a lot of wooden and metal stairs don't have the tread boards flush with the kick boards (?)
[18:02:17] <z64555> s/kick board/riser
[18:03:22] <ToAruShiroiNeko> http://architectureideas.info/2013/07/stair-shapes/
[18:03:33] <ToAruShiroiNeko> it actually turns like the 90 winder stairs at the end
[18:03:44] <ToAruShiroiNeko> but thats something I dont want to think about right now
[18:04:17] <z64555> true. First, you need some 5-bolt wheel hub assemblies
[18:04:38] <ToAruShiroiNeko> Rocker-bogie would not have too much trouble climbing stairs if the wheel was large, with the same height of the stair or close to it
[18:05:04] <ToAruShiroiNeko> no?
[18:05:33] <z64555> dunno. I'm an electrical engineer with only a dash of mechanical knowledge
[18:05:52] <ToAruShiroiNeko> well, my proof of concept will test that
[18:06:11] <ToAruShiroiNeko> so which wheels should I go for?
[18:06:49] <ToAruShiroiNeko> I have 12.5kg per wheel for 50kgs probably
[18:07:34] <z64555> 50Kgs * 2.2 / number of wheels. :)
[18:07:56] <z64555> Hey, 2.2 works for signal sampling, why not elsewhere?
[18:08:23] <ToAruShiroiNeko> its 4 wheels because its Rocker-bogie
[18:08:49] <ToAruShiroiNeko> I am pretending it has only 4 of the 8 weels touching to give it extra durability
[18:08:49] <z64555> ah
[18:09:08] <ToAruShiroiNeko> and I dnot expect it to carry more than 30 kgs with 10kg for the hardware
[18:09:14] <z64555> so 12.5Kg should be more than enough
[18:09:16] <ToAruShiroiNeko> plus 10kg extra
[18:09:48] <ToAruShiroiNeko> I probably wouldnt load it with more than 20kg
[18:10:07] <ToAruShiroiNeko> once I build my dumb cart I will go shopping with it to see how well it performs
[18:10:16] <ToAruShiroiNeko> it wont have balance issues since I will be holding it
[18:12:54] <ToAruShiroiNeko> like
http://www.aliexpress.com/item/4Pcs-RC-1-10-Rock-1-9inch-Beadlock-Wheel-Rim-96mm-Tyre-Tires-For-Crawler-RC4WD/32522781730.html
[18:13:10] <ToAruShiroiNeko> this one is too expensive imho
[18:14:49] <z64555> yeah, rock climbers tend to be
[18:15:47] <z64555> hm. They'll give you the best grip for going up stairs, for sure, but they're just as likely to tear up said stairs
[18:17:03] <z64555> anonnumberanon: you see my rings of power? :D
[18:17:13] <ToAruShiroiNeko> tear the stairs? how?
[18:17:51] <ToAruShiroiNeko> I can give it a stair climbing mode where it can rely on a bit more than mechanical gain
[18:18:15] <z64555> eh, this is a gut feeling, sorry
[18:18:30] <ToAruShiroiNeko> its no good if it leaves rubber marks on it
[18:19:09] <ToAruShiroiNeko> I was hoping one wheel to hold the weight while the other climbed
[18:21:54] <z64555> oh he did see my power ring
[18:31:59] <z64555> ahah...
[18:32:42] <z64555> That moment when, you buy screws and nuts the wrong size, but then relize the holes are the perfect size to be tapped to fit the screws
[18:34:30] <z64555> I bought some fasteners to replace the cheap-ass all-thread I used to hold the electronics platters to the metal chassis
[18:35:21] <z64555> oh, shoot, forgot to pick up something to hold the battery down
[18:35:31] <z64555> zip ties are... inneffective
[18:37:07] <deshipu> I like velcro for batteries
[18:37:21] <deshipu> and plastic bolts for electronics
[19:15:36] <z64555> heh. typical
[19:16:01] <z64555> Tried sticking the power rings on the quad, and they're too thick to fit between the arm rods and the bottom platter
[19:16:58] <z64555> I can cut the zip ties and slap them on either side of the hub, they have just enough room there
[19:17:19] <z64555> although, the bottom platter really isn't providing support for anything other than the battery
[19:17:31] <z64555> which I can strap it to the arms
[19:18:32] <z64555> or to the top platter
[19:20:12] <deshipu> metal bolts and screws are so heavy
[19:21:44] <z64555> yeah, but this is a prototype. it's built for abuse
[19:23:27] <z64555> hm, i think i'll keep the bottom platter on. Gives me a place to mount some bottom facing sensors or cameras
[21:20:02] <RustyShackleford> https://www.amazon.com/gp/product/B00LNCDGKU/ref=ox_sc_act_title_3?ie=UTF8&psc=1&smid=A2B7MUSQY6UNFM
[21:20:11] <RustyShackleford> I'm thinking about buying a crank standing desk like this
[21:20:25] <RustyShackleford> and then possibly adding my own motor so I don't have to hand crank it
[21:21:14] <RustyShackleford> what kind of motor do I need? There are several kinds of electric motors
[21:21:47] <RustyShackleford> reviews make it seem like its geared very low, 6 turns per 1 inch of desk height. Probably don't need anything with too much torque
[21:21:52] <Jak_o_Shadows> I'd be tempted to try something like a window wiper motor
[21:22:49] <Jak_o_Shadows> geared very low probably means more torque
[21:23:04] <RustyShackleford> you're right I have it backwards
[21:24:40] <RustyShackleford> there's a cool store near me that sells all kinds of parts, plenty of electric motors salvaged from stuff
[21:25:43] <RustyShackleford> i'm just not sure what to look for hah
[21:39:47] <Jak_o_Shadows> Probs not an AC motor
[21:39:54] <Jak_o_Shadows> they tend (as a general thing) to like to spin
[22:07:41] <RustyShackleford> Jak_o_Shadows, you mean to spin constantly?
[22:07:57] <RustyShackleford> instead of infrequent bursts
[22:15:25] <Jak_o_Shadows> Sort of. More that they like to do lots of revolutions
[22:15:41] <Jak_o_Shadows> Whereas DC motors are probably better at slow grindy motion.
[22:15:46] <Jak_o_Shadows> As a general thing
[22:15:48] <Jak_o_Shadows> can get around it
[22:44:55] <z64555> ok, brain's back up and running, but dang does it need a serious defrag
[23:30:55] <anonnumberanon> z64555, right now they are inert, your rings of power, show me them supplying some juice!!!
[23:33:54] <z64555> If things are well, they'd look exactly the same but connected to other bits
[23:34:13] <z64555> if things are not well, then the insulation would be melted off and the platter would be on fire or near it
[23:37:43] <Jak_o_Shadows> my joysticsk arrived
[23:37:51] <Jak_o_Shadows> ...all 6 of them. I can't recall ordering more than 4
