#robotics Logs

Apr 21 2015

00:44 rue_house oooo
00:45 Jak_o_Shadows graphs are always nice
00:45 rue_house electronic load works
00:46 rue_house I was current sweeping some power adapters
00:46 rue_house the reason they open circuit votlage is so high is because they have about 9 ohms impedence,
00:46 rue_house at rated current they seem to consistantly be 1V over reated votlage
00:47 rue_house so...
00:47 rue_house lets make one up
00:47 rue_house 6V 1500mA
00:47 rue_house so, at 1500mA it would be 7V
00:47 rue_house over the 1500mA it would go up at 9 ohms
00:48 rue_house zippo:/files/temp# ohm -r 9 -i 1.5
00:48 rue_house Wattage is: 20.250000
00:48 rue_house Current is: 1.500000
00:48 rue_house Voltage is: 13.500000
00:48 rue_house Resistance is : 9.000000
00:48 rue_house so... I would expect an open circuit voltage of
00:48 rue_house 20.5V
00:49 rue_house hopefully it would be less than 9 ohms
00:49 rue_house how about 6 ohms...
00:49 rue_house zippo:/files/temp# ohm -r 6 -i 1.5
00:49 rue_house Wattage is: 13.500000
00:49 rue_house Current is: 1.500000
00:49 rue_house Voltage is: 9.000000
00:49 rue_house Resistance is : 6.000000
00:50 rue_house so 16V O.C.
00:51 rue_house it seems logical they would limit the internal power loss
00:51 rue_house I should look at those numbers later
00:51 rue_house I'd bet there is a ballpark realted to adapter size
00:52 rue_house (unregulated magnetic adapters)
02:15 just_corey hey rue you here?
06:36 malinus It only took one week for smart-prototyping from order to shipping of my pcb.
06:36 malinus That's pretty impressive, considering the price ($10 for 10 2-layer boards, 5x5cm)
07:09 malinus anyone making this one https://www.youtube.com/watch?v=ABzjUf3E_0c
07:09 Jak_o_Shadows I am tempted
07:09 Jak_o_Shadows It would be cool.
07:10 malinus Very hard, probably
07:11 malinus I want someone to make a hobby-prototype, at least.
09:10 rue_house just_corey, hey!
09:10 rue_house finally online!
09:18 rue_house did you not see how its made?
18:20 Hyratel hey, anyone here built their own flight joystick before?
19:27 rue_house ooo thats a 3d printer project if I ever heard one
19:38 Hyratel rue_house, right?
19:38 Hyratel the Gravis Blackhawk joystick has an excellent feel
19:38 Hyratel and it has a PISO shift register in the handle that should make interfacing trivial
19:39 Hyratel the only problem is it has to be installed all as one big part - the baseplate holds the axis arms
19:39 Hyratel while the top half of the base clamshell holds the pots
19:40 Hyratel http://www.amazon.com/Gravis-G10171B-Blackhawk-Digital-Joystick/dp/B00000K4TP
19:41 orlock new job yay
19:41 Hyratel rue_house, there's a bunch of not-quite-great joysticks out there, but they all seem to fall flat in one or anbother dept
19:41 orlock there is a product assembly floor here
19:42 orlock they build robots
19:42 Hyratel problem with the Blackhawk Digital is it's not a simple Gameport device
19:42 Hyratel it has to load a custom driver that turns a gameport into a soft serial port
19:42 Hyratel I bet it's I2C tho
19:49 Hyratel rue_house, ping)))
22:18 rue_house whats going on>?
22:37 Hyratel any suggestions for finding a linear potentiometer with a 3/16" shaft?
22:37 Hyratel digikey's selection is nonexistent
22:39 rue_house just_corey, you awake!?
22:40 rue_house linear and a round shaft dont go togethor
22:40 rue_house do you mean a lienar taper?
22:42 rue_house http://www.aliexpress.com/item/Delta-75mm-Length-sound-console-dimming-Slide-potentiometer-double-straight-slide-B10k-15mm-4-2/32213118556.html
22:47 Hyratel yes, linear taper
22:48 rue_house http://www.aliexpress.com/item/10pcs-Potentiometer-Pot-B10K-10K-Linear-shaft-20mm/1124604940.html
22:52 Hyratel what shaft size
22:54 Hyratel if there was room to drill out the shaft sockets on the device I'd do that, but there's very little clearance