#robotics Logs

Oct 14 2015

00:08 anonnumberanon The two stronger servos are mg959 by the way. (cost a fortune at $30 each).
00:08 zhanx 30 is cheap
00:08 anonnumberanon cheap for the torque they bring, IF these things last
00:09 zhanx i paid 63 each for mine but they stripped gears fast
00:09 anonnumberanon I suspect some of the mg995s will may break if I'm not careful with the motions.
00:09 anonnumberanon the mg959?
00:09 zhanx maybe been 7 years
00:10 anonnumberanon The ones I have are mg959 version 2. 7 years ago, I think those were version one still.
00:11 zhanx just remember holding torque will kill them
00:11 zhanx most are meant to move not hold
00:12 anonnumberanon That spider you made still around?
00:12 zhanx no i made a mistake and charged the battery in the robot
00:12 anonnumberanon Would have been good to have a switch between the battery and the rest.
00:13 anonnumberanon What did you kill?
00:13 zhanx well when the rest is abs plastic and the battery goes it all melts
00:13 anonnumberanon ahh, overheating..
00:14 zhanx happens
00:14 anonnumberanon Wish you had caught that on video.
00:15 anonnumberanon So from research I determined that the mg996r are a newer, crappier version of mg995.
00:15 anonnumberanon It's a weird market.
00:15 zhanx shoot i built it in iraq and lost it in afagan
00:16 anonnumberanon Opened up both cases and the mg996r has a shorter motor, not sure if it means less power..
00:16 zhanx less power yes
00:16 zhanx smaller winding
00:17 anonnumberanon Were you in the engineers section of the US armed forces?
00:17 anonnumberanon or just playing around with robots?
00:17 zhanx nope
00:17 zhanx door kicker that is smart
00:18 anonnumberanon I'd just kick the door open with a light frag.
00:18 anonnumberanon follow with flash
00:18 anonnumberanon :)
00:18 zhanx and why you wouldn't live
00:19 zhanx not being mean
00:19 anonnumberanon What's the proper way to do it?
00:19 zhanx controlled charge
00:19 zhanx that way you know when its gonna open
00:20 zhanx with a delay on the flash bangs after the initial blast
00:20 anonnumberanon If you're lucky enough to not have been seen on your way to the door :)
00:20 zhanx who care
00:20 zhanx care
00:20 zhanx ugh
00:21 anonnumberanon My skin which doesn't like piercing from 7.52 does.
00:21 zhanx its not a fun time for sure
00:22 anonnumberanon If I was there I'd have been too tempted to distribute cheap laptops to the kids with Linux, but then I'm sure they would have been sent back to the makers of IEDs.
00:22 zhanx my 82 year grand farther in law spent 4 years in germany
00:23 zhanx IED's are cheaper than that
00:23 zhanx 2 hack saw blades and a cushion
00:24 zhanx clothes pin and foil
00:24 zhanx etc etc
00:24 anonnumberanon Those are the IEDs which hit the ones who lived to tell the story and describe the devices... hehe
00:24 anonnumberanon Meh, I don't pretend to know anything about that subject though.
00:25 zhanx its ok
00:25 zhanx make robots its happier, in a crappy mode
00:25 anonnumberanon Well I'm still being kind of edgy, my bot is meant to fight other bots.
00:26 zhanx needs awesome programming then
00:28 zhanx fyi old floppy disk drives are worm gear ish, you can use a weight to stablize the bot
00:28 anonnumberanon Yeah. I see this as a pretty intense discovery of very practical programming applications. I've already drone a quadcopter controller so I can use the accelerometer/gyroscope chips, but the walking motions, and turning them on according to the sensor's feedback, may be a great challenge.
00:28 zhanx but a fun one
00:29 anonnumberanon yup, wouldn't do it otherwise
00:31 anonnumberanon The way I look at it is that hopefully in the process, I get to find real-life applications derived from this project.
00:32 zhanx not peace on earth? what good are you geessh
00:34 anonnumberanon Well let's be hones, this is a hard project. I chose to do this after the quadcopter, which I thought was really hard, and I was looking for another hard project after I graduate, so I don't stop being productive and learning/researching.
00:38 anonnumberanon It's not like I was recruited by JPL or SpaceX at graduation. sigh...
00:39 zhanx Raytheon and i turned it down. i was wrong
00:42 anonnumberanon I'm very interested in working on technologies that could help spacecraft grapple asteroids for landing.
00:42 anonnumberanon Lots of software, intricate mechanical engineering as well, for a change. Maybe some chemical.
00:43 orlock Have you read Seveneves?
00:43 anonnumberanon No.
00:43 orlock Worth reading, if thats something you are interested in
00:44 anonnumberanon I do have Cryptonomicon on my shelf that I haven't opened yet. lack of time. I love hard sci-fi, is Seveneves like that?
00:44 orlock Yes
00:44 orlock Lots of stuff related to asteroid mining, etc
00:45 anonnumberanon Yes I'm fascinated by that, I don't know why, kind of the thought of not knowing what they contain. Could be a gold rush all over again.
00:45 anonnumberanon BUT WITH SPACESHIPS
00:45 orlock Cryptonomicon is good, but has small doses of "magic!"
00:45 orlock alongside many of his other books
00:46 orlock but Seveneves is pretty hard sci fi
00:47 anonnumberanon I've literally researched things I could work on my own and related to the space industry but I didn't really find any ideas, related to Electrical/Electronics/Computer Engineering.
03:40 anonnumberanon what's the link for rue's power supply I'm trying to source the volt and amp meters used in it
08:43 itc hi
09:29 mr_snowf1ake hi itc, what's up?
10:34 mr_snowf1ake what are your thoughts on mpu6050 vs pololu minimu (lsm303d + l3gd20h)?
10:35 mr_snowf1ake i like the interrupt feature on the mpu6050
13:38 wolfmanjm i've used both, the miniimu has 9 degrees which does correction, many 6050 one s are only 6 axis. the 6050 can offload the calculations from the mcu which is good if you have a slow mcu. the miniimu needs to do the kalman filtering etc on the mcu
13:55 mr_snowf1ake wolfmanjm: does the mpu9250 do the sensor fusing on chip as well (correction via compass)?
14:01 wolfmanjm mr_snowf1ake: yes it can, I am not sureif it will do the drift correction if an external compass is attached as mine only has 6 axis and no compass.
14:01 mr_snowf1ake wolfmanjm: i thought the mpu9250 had the compass built in?
14:01 wolfmanjm oh 9250 I am not familiar with
14:02 wolfmanjm I only have the 6050
14:02 mr_snowf1ake yeah, okay
14:02 mr_snowf1ake same
14:02 wolfmanjm the problem is the firmwre that does the fusing on the 6050 is not open source so yo have to download a binary to it
14:02 mr_snowf1ake yeah.
14:03 mr_snowf1ake hmm... actually, can you just download that from an arduino or something?
14:03 mr_snowf1ake how does that work?
14:03 wolfmanjm the freeimu stuff uses the 6050 and does the fusing and drift correction externally
14:03 mr_snowf1ake i figure it must be over i2c
14:03 wolfmanjm yea you load it over I2C
14:03 mr_snowf1ake but it doesn't /come/ with that preinstalled eh?
14:03 wolfmanjm no
14:03 mr_snowf1ake alright
14:04 mr_snowf1ake thanks
14:05 wolfmanjm http://www.i2cdevlib.com/devices/mpu6050#source Jeff Rowbergs stuff loads the 6050 firmware but it is a binary blob
14:08 mr_snowf1ake huh.
14:08 mr_snowf1ake interesting
14:08 mr_snowf1ake yeah, idk, while i do like things that are open source, if the binary blob works well i guess i'm also okay with that
14:15 mr_snowf1ake sounds like mpu 9250 sensor fusion doesn't do compass :/
18:22 SpeedEvil http://i.imgur.com/vzurPyb.gif Now I'm wondering how to make a kitty a little backpack.
18:23 Snert_ thats just bizarre. Spidycat
20:42 rue_shop4 that is crazy