#robotics Logs

Oct 10 2015

00:38 mrdata my sister removed her fingerprints completely
03:34 deshipu yawn
03:34 deshipu veverak: not at that hour
03:35 deshipu rue_shop3: http://www.aliexpress.com/item/Free-Shipping-Wltoys-V959-Parts-Water-Jet-Pistol-Component-For-WL-V959-4CH-RC-Quadcopter-UFO/1844006198.html
04:14 veverak deshipu: as I looked into your code, your leg moves are timed for each frame?
04:14 veverak I mean, "this moves takes 4 frames.."
05:11 deshipu yes
07:14 veverak I see
07:15 veverak it looks like last night I decidet I want to know how much time remains for servo to reach it's position, and made "estimate_move_time(point)"
07:15 veverak hmm
11:44 deshipu that's difficult
11:44 deshipu as the servo has a PID controller in it
11:47 veverak deshipu: made "speed" attribute for each servo
11:47 veverak (degree/sec)
11:47 veverak hmm, will see if it will work or not :)
11:50 deshipu well, you can always move the servos slower than their max speed
11:50 deshipu by sending them the next position every time
12:10 deshipu veverak: I got a table saw!
12:15 veverak !! :D
12:15 verak is 3d printing leg
12:15 veverak :)
12:27 SpeedEvil deshipu: https://www.youtube.com/watch?v=u7sRrC2Jpp4 - you need to watch
12:32 SpeedEvil @4:20 if you're not watching it all
13:22 deshipu SpeedEvil: well, it's a fretsaw
13:22 deshipu SpeedEvil: not rotary
13:23 deshipu or scrollsaw?
13:27 SpeedEvil ah
13:27 SpeedEvil yeah - it's really hard to kill yourself with a scrollsaw.
13:29 deshipu I will keep trying
13:29 SpeedEvil That's the spirit.
13:30 deshipu one thing I already determined is that I can't really cut acrylic with it
13:30 deshipu it melts and welds back right after the blade
13:31 deshipu depron works fine, though
13:31 SpeedEvil you may find coolant helps
13:31 SpeedEvil If you can
14:10 deshipu or really slow cutting speed
14:11 deshipu or wider blade
14:33 veverak deshipu: table saw seems like something for big projects
14:34 deshipu scrollsaw
14:34 deshipu it's a scrollsaw
14:35 veverak nice
14:36 Hyratel deshipu, as mentioned, cooling the blade, lower speed
14:36 Hyratel you might get good results with just air cooling
14:37 deshipu I can connect a vacuum cleaner to it
14:37 deshipu sucking is not as good as blowing, but it's something
14:38 deshipu I wonder if wood or metal sawblades would be better
14:38 Hyratel deshipu, put the hose on the exhaust
14:38 Hyratel wood, definitely
14:38 deshipu the tiny teeth on the metal ones would get clogged, I guess
14:38 Hyratel you need the larger 'bite' of the wood blades
14:38 Hyratel also that
14:38 deshipu or what's the word
14:43 deshipu I will try that on Monday
14:43 deshipu tomorrow is the national no-noise day in here :(
14:44 deshipu of course church bells are the exception
19:46 veverak deshipu: I suppose I will print soem parts for tote
19:46 veverak I suppose making simple holder of two servos, which are shifted 90 degrees should e possible
19:47 veverak (reason is that avoiding glueing it together sounds promising)
21:28 RobotDuty Hello! According to the discussion last night, I did some maths to understand the concepts you explained in excel sheet, but I'm still wondering about the mechanical of gear connected with the axle or the wheel's hub. Can you explain it to me?
21:29 Jak_o_Shadows I don't think I was there last night
21:29 Jak_o_Shadows But it is something I can probably explain
21:30 RobotDuty Good :)
21:30 RobotDuty (I read you)
21:35 Jak_o_Shadows So what's your problem?
21:36 RobotDuty Hum, to understand the mechanical of the gear connexion (wheel - motor)
21:36 RobotDuty or "hub" - motor
21:36 RobotDuty I don't know as you see it :S
21:39 RobotDuty Something like that : http://etotheipiplusone.net/pics/moter/rage44.jpg
21:39 Hyratel RobotDuty, a wheel or gear attached to the axle, and the axle turns to turn the wheel is a "live axle" and the wheel or gear has to be attached in some way
21:39 RobotDuty Maybe you can point me some references or resources that can help me understand the connection
21:40 Hyratel this is done by Splines (many small grooves longwise on the shaft, and matching grooves inside the wheel hub)
21:40 Hyratel or by a set screw
21:40 Jak_o_Shadows You may be best just going and looking at a bicycle
21:40 Jak_o_Shadows Or a keyway
21:40 Hyratel or a machine Key, which matches a slot in the hub and shaft
21:40 Hyratel or a Flatted/D shaft, which matches a flat spot inside the hub
21:41 Hyratel or a shaped shaft, such as Hex or Square shaft
21:41 Hyratel have you ever played with legos?
21:41 Hyratel they use a style between several -0 the cross shaft
21:41 RobotDuty Yes :p
21:48 RobotDuty Hyratel: http://postimg.org/image/uxgsem7rj/ like this ?
21:49 Hyratel bad view
21:49 Hyratel oh
21:49 Hyratel no
21:49 Hyratel actually
21:49 Hyratel that's a dead axle
21:49 RobotDuty a dead axle mean I can't remove it?
21:49 Hyratel dead axle means the axle does not rotate
21:50 Hyratel it means the axle is only load bearing. it does not transfer torque
21:50 RobotDuty Ok, I understand the dead axle :)
21:50 Hyratel google live axle vs dead axle
21:50 RobotDuty So, I need a none-dead axle?
21:52 RobotDuty Is it possible to build two very small live axles ?
21:52 Jak_o_Shadows what are you actually trying to do?
21:53 RobotDuty A Robot that move on 4 wheel with one drill motor (2 wheel for stability) and he can move up to 300 lbs (like a bulldozer robot)
21:56 RobotDuty Of course, I do need a solid axle I guess.
21:56 RobotDuty like a "panhard rod"
21:58 Hyratel https://dl.dropboxusercontent.com/u/33593534/images/Robot/DSCN2011-1k2.jpg
21:59 Hyratel https://dl.dropboxusercontent.com/u/33593534/images/Robot/DSCN2016-1k2.jpg
22:00 RobotDuty Ha, the motor move the chain?
22:01 RobotDuty (nice robot by the way :p)
22:03 RobotDuty What does block the chain from going to the left ?
22:03 RobotDuty in the first picture
22:09 Jak_o_Shadows There's spokes there I think
22:13 RobotDuty Ok, that sounds very complex for a starter in robotics, but I will do the best to understand it. Thanks you guys :)
22:21 Hyratel jackburton, spokes?
22:22 Hyratel sprockets turn drivechain
22:23 Jak_o_Shadows ah. That is the word
22:23 Jak_o_Shadows teeth!