Back
[03:47:17] <deshipu> where would you rather have them?
[03:59:26] <Jak_o_Shadows> At the base.
[03:59:48] <Jak_o_Shadows> but it's a pretty different system.
[04:00:11] <Jak_o_Shadows> you move the complicated joints, but really, they aren't too bad
[04:19:43] <deshipu> then you would need at least two servos per "leg", no?
[04:20:24] * veverak is watching that video third time
[04:21:56] <deshipu> the 2mm headers arrived, now I can have my esp8266 modules pluggable :)
[04:23:19] <veverak> (y)
[04:23:21] <veverak> :)
[04:25:14] <deshipu> I can't believe I didn't think about this before
[04:26:18] <Jak_o_Shadows> Nah, you can do it with one
[04:26:50] <Jak_o_Shadows> I'm not 100% sure on what impact it has on range of motion
[04:26:56] <Jak_o_Shadows> range of motion of parallel manipulators is hard
[04:27:37] <Jak_o_Shadows> Obviously the ideal is linear actuators though
[04:29:22] <veverak> hmm
[04:29:24] <veverak> damn it
[04:29:27] * veverak is in tight spot
[04:29:41] * veverak got part that can be reasonably only 3d printed
[04:29:52] <veverak> and can't think of suitable replcement
[04:30:07] <veverak> so question is if I shouldn't give up on "no 3d printer needed"
[04:30:28] <deshipu> veverak: the camera gimbal?
[04:30:48] <veverak> deshipu: leg strengthening
[04:30:59] <veverak> gimbal I was able to figure out
[04:31:03] <deshipu> veverak: chave you considered chiseling in granite? ;)
[04:31:09] <deshipu> have
[04:31:29] <deshipu> iron casting
[04:31:34] <deshipu> there are lots of ways
[04:32:01] <veverak> hmmm
[04:32:16] <veverak> deshipu: I wanted something that anybody could create
[04:32:23] <veverak> so, bring as many ways to build parts as possible
[04:32:25] <veverak> :/
[04:32:55] <veverak> deshipu:
https://github.com/Schpin/schpin-chassis/blob/master/tote/scad/strengthen/servo.stl
[04:33:01] <veverak> this part holds leg base servos together
[04:33:21] <veverak> not helds exactly, just helps the doublesided tape
[04:38:38] <Jak_o_Shadows> That is REALLY neat of github
[04:39:43] <Jak_o_Shadows> You could make it out of a solid block, but it'd be pretty wasteful
[07:21:29] <veverak> nah
[07:23:17] <veverak> really considering to remove "all parts can be no3d printed" rule
[07:24:02] <veverak> (not counting iron casting, and lathe)
[07:24:08] <[VEGETA]> veverak, good to talk to you again xD
[07:24:39] <[VEGETA]> I didn't log for a week or so because of some circumstances... ramadan and stuff
[10:44:32] <pokmo> are the motors used in typical camera gimbals steppers?
[10:44:53] <deshipu> define "typical"
[10:45:13] <veverak> deshipu: battery fits perfectly between servos
[10:45:37] <deshipu> veverak: yeah, i put it there for some of my totes
[10:45:45] <pokmo> deshipu: something like
http://www.feiyu-tech.com/products/6/
[10:46:37] <veverak> deshipu:
http://squirrel.veverak.org/laptop/scad/gama.png
[10:47:28] <deshipu> pokmo: that one uses brushless motors
[10:48:26] <pokmo> deshipu: but are they steppers?
[10:48:40] <deshipu> no
[10:48:49] <pokmo> deshipu: but how do you tell?
[10:49:12] <deshipu> pokmo: they write it on the specs page
[10:50:57] <deshipu> "高精度无刷电机直驱控制"
[10:51:07] <pokmo> deshipu: if they aren't steppers, would that mean some sort of encoder is used?
[10:51:21] <veverak> usually yeah
[10:51:23] <veverak> :)
[10:51:35] <deshipu> pokmo: possibly, or just a feedback loop with an accelerometer
[10:52:12] <deshipu> you know, they don't need to know the relative angles of the motors, just the position of the whole camera
[10:52:25] <pokmo> true
[10:52:47] <veverak> deshipu: have you got any upgrades to your servo_controller board?
[10:52:54] <veverak> https://hackaday.io/project/9131-servo-controller
[10:53:01] * veverak is thinking about making one or two
[10:53:02] <deshipu> veverak: no, it's pretty much finished
[10:53:09] <veverak> goo
[10:53:11] <veverak> d
[10:53:15] <deshipu> veverak: other people have made other versions, though
[10:57:51] <veverak> good
[11:02:36] <deshipu> veverak: by the way, I'd rather use that code with
https://hackaday.io/project/9067-universal-servo-breakout
[11:03:22] <veverak> ok
[11:39:22] <rue_house> wow, you people are STILL trying to control servos
[15:25:24] <mrdata> rue_house, whats wrong with trying to control servos?
[15:25:30] <mrdata> the part where it's all try and no success?
[15:33:25] <mrdata> i made a servo controller with a 555 timer and a potentiometer
[15:33:36] <mrdata> fine tuning was a chore but it works great
[16:51:39] <rue_house> I used a tiny13, and in the same 8 pin, swith less components, and no tuning, was able to control 2 servos :P
[19:08:32] <SpeedEvil> https://xkcd.com/560/
[19:08:43] <SpeedEvil> oops
[19:08:52] <rue_house> how much current do you think the tail rotor motor of a copter takes at full load?
[19:11:03] <rue_house> aha, 0.12W
[19:13:19] <rue_house> https://www.precisionmicrodrives.com/product/106-002-6mm-dc-motor-12mm-type
[19:31:04] <codepython777> if i have to have a battery that i can step up from, vs step down - which one do i pick and why?
[19:33:06] <z64555> thats... not enough info. Because with a battery you want power
[19:33:18] <z64555> not just current, or just voltage
[19:34:26] <z64555> Having a battery with a higher voltage than needed can be used to power circuits that use a lower voltage easier/cheaper than it would be if it where the reverse
[19:34:47] <z64555> ...not sure if that made sense, sorry. half asleep
[19:36:16] <z64555> one thing about the step-down method, Voltage regulators and voltage dividers are typically inefficient as compared to boost mode SMPC circuits
[19:36:46] <z64555> with voltage dividers being the least efficient in terms of power transfer
[19:37:47] <z64555> but going back to my earlier statement. Supposed you have a battery with a large capacity, but low voltage. and a battery with a higher voltage, but lower capacity
[19:38:07] <z64555> which one do you choose?
[19:43:32] <codepython777> z64555: I'm trying to run a laptop type computer that requires 19v 6.3A - and am deciding for a battery
[19:46:38] <Wetmelon> 6.3A?
[19:46:51] <Wetmelon> Eh that's only 119W, fair enough
[19:47:04] <orlock> Sounds like common laptop requirements
[19:47:43] <Wetmelon> You pick one with a high energy density and low power density, like an LG HG2
[19:54:33] <SpeedEvil> Or you just pick a lower power platform
[19:56:10] <codepython777> Wetmelon: I was thinking of just using a lipo - 4S - 18.5V
[19:56:39] <codepython777> Or I could do 5S
[19:56:40] <Wetmelon> That's fine, but it won't last as long
[19:56:48] <SpeedEvil> codepython777: Why do you need that much power?
[19:56:55] <SpeedEvil> 4s is not 18.5V
[19:57:15] <codepython777> 5S or 6S - sorry not 4S or 5S
[19:57:36] <SpeedEvil> 5s is 11.8-21
[19:57:57] <SpeedEvil> why can't you use the existing battery?
[19:57:59] <codepython777> 5S = 18.5
[19:58:06] <SpeedEvil> No, it's not.
[19:58:20] <SpeedEvil> That is the nominal voltage.
[19:59:28] <codepython777> SpeedEvil: so a 5S Lipo rated at 18.5V - what does it actually supply?
[19:59:46] <SpeedEvil> From 11.8-21V or so from flat to full
[19:59:58] <SpeedEvil> 2.8-4.2V/cell.
[20:00:12] <SpeedEvil> And you need a protection circuit to manage the battery.
[20:00:14] <SpeedEvil> why can't you use the existing battery?
[20:00:34] <codepython777> SpeedEvil: Which existing battery? Its a machine I put together - 120W PSU
[20:00:45] <codepython777> 19v
[20:00:57] <SpeedEvil> 'laptop type computer' tends to imply to most people a laptop
[20:01:15] <codepython777> ah ok
[20:01:29] <SpeedEvil> What is the power supply input voltage specced to ?
[20:01:30] <SpeedEvil> Max/min
[20:01:32] <codepython777> so i'll need a voltage step-up/down from the 5S
[20:01:42] <codepython777> 19v +- 3%
[20:01:52] <SpeedEvil> yes.
[20:01:55] <SpeedEvil> Why so much power?
[20:02:04] <codepython777> its an i7 box
[20:02:49] <codepython777> how do i power it correctly using a lipo?
[20:04:39] <SpeedEvil> http://www.ebay.co.uk/itm/16A-Battery-BMS-Protection-Board-Balance-3S-4S-5S-Packs-Li-ion-lithium-Battery-/172017403295?hash=item280d09459f:g:Y3UAAOSw7FRWX2Yh - for example. plus
[20:05:36] <SpeedEvil> http://www.ebay.co.uk/itm/10A-DC-DC-BUCK-BOOST-MODULE-STEP-DOWN-UP-5-30V-TO-1-30V-WITH-CURRENT-CONTROL-/171674659434?hash=item27f89b6a6a:g:PxkAAOSwX~dWp4ir
[20:05:56] <SpeedEvil> you will need a fan
[20:06:25] <SpeedEvil> The first is an example of a battery protection circuit that will stop the battery dying on first discharge you accidentally leave it on
[20:13:44] <SpeedEvil> Very, very few robots require an I7
[20:14:54] <codepython777> SpeedEvil: I was thinking of just using a voltage alarm for the battery
[20:15:02] <codepython777> so i just need the buck converter?
[20:15:30] <SpeedEvil> For that size of lithium pack, the protection board is free.
[20:15:51] <SpeedEvil> Compared to even a small chance of once shorting it, or running it down
[20:15:56] <codepython777> SpeedEvil: I'll need to connect that board to the balancer pins
[20:16:09] <SpeedEvil> yes, it also needs connected to the balance pins
[20:16:15] <codepython777> SpeedEvil: is there a plug and play version of that?
[20:16:26] <SpeedEvil> probably, that was the first one I found.
[20:16:34] <SpeedEvil> search '5s protection board
[20:16:47] <SpeedEvil> by 'welding' they mean solder a link
[20:20:58] <codepython777> SpeedEvil:
http://www.aliexpress.com/item/DC-Boost-Converter-DC-8-40V-to-12-60V-10A-160W-Adjustable-Power-Supply-Module-DC/32595856945.html?spm=2114.01010208.3.2.2BlvAa&ws_ab_test=searchweb201556_8,searchweb201602_3_10017_507_401_10040,searchweb201603_6&btsid=32e3d6bd-f559-4934-9556-f1153492c297 ?
[20:22:09] <codepython777> doesnt look as nice as the one you pointed to though
[20:22:18] <SpeedEvil> perhaps. It will need a fan
[20:24:30] <codepython777> SpeedEvil:
http://www.aliexpress.com/item/Numerical-control-digital-display-DC-DC-DC-booster-module-420W-Constant-voltage-constant-current-module/32459846865.html?spm=2114.01010208.3.27.kxtOMm&ws_ab_test=searchweb201556_8,searchweb201602_3_10017_507_401_10040,searchweb201603_6&btsid=f7c8cb71-e00f-4263-afda-f66ca8ce5f2d - looks nice
[20:25:16] <SpeedEvil> In principle
[20:26:18] <codepython777> SpeedEvil:
http://www.aliexpress.com/item/High-Efficiency-95-DC-DC-600W-IN-12-60V-OUT-12-80V-Boost-Converter-Step-Up/32374850067.html - will this not do step down?
[20:59:41] <SpeedEvil> yes
