From rich.gibson at gmail.com Wed Mar 5 19:58:28 2008 From: rich.gibson at gmail.com (Rich Gibson) Date: Wed Mar 5 19:58:43 2008 Subject: [dorkbotsebastopol-blabber] No dorkbot tonight... Message-ID: I didn't send out an announcement, but no dorkbot tonight, I have another commitment. Cheers, Rich From steve at chalem.com Mon Mar 17 16:15:19 2008 From: steve at chalem.com (Steve Chalem) Date: Mon Mar 17 16:16:01 2008 Subject: [dorkbotsebastopol-blabber] Sebastopol Dorkbot Build Meeting this Week Message-ID: <3606B5BAD467A349AC94B0D05164DBD603BE5384@EXVBE014-13.exch014.msoutlookonline.net> We'll be meeting this week at my shop to start integrating the flea circus*. Doors open at 6pm, meeting starts at 7pm. My shop is at 4019 Sebastopol Rd. in Santa Rosa. If you haven't been there, please email me for additional directions. --Steve * (The "flea circus" is mine and Bruce L's motion-control learning project. Bruce has built a framework about 2.5 feet across and 1.5 feet tall with three towers. At the top of each tower is a stepper motor that will drive a "drum" with thread wrapped around it. The three threads will meet in the middle and support a small weight. By winding and unwinding each spool, the weight can be moved in three dimensions. I've built a driver box with three EZ-Driver stepper-motor drivers, three limit=sense lines, and a 25vdc power supply; and I'm building a control box with a joystick (for the x- and y-axes) and a pot (for the z axis). Wednesday, we're going to hook this all together with an Arduino and try to make it do something. Helpers, kibbitzers, torta-fetchers, and people who just want to stand around and talk are all welcome.) From bsilva at sonic.net Mon Mar 17 16:59:32 2008 From: bsilva at sonic.net (bsilva) Date: Mon Mar 17 16:59:44 2008 Subject: [dorkbotsebastopol-blabber] Sebastopol Dorkbot Build Meeting this Week In-Reply-To: <3606B5BAD467A349AC94B0D05164DBD603BE5384@EXVBE014-13.exch014.msoutlookonline.net> References: <3606B5BAD467A349AC94B0D05164DBD603BE5384@EXVBE014-13.exch014.msoutlookonline.net> Message-ID: To all: Any opinions on Beer/Sodas/Pizza/Chinese/etc? Brad On Mon, 17 Mar 2008, Steve Chalem wrote: > We'll be meeting this week at my shop to start integrating the flea > circus*. Doors open at 6pm, meeting starts at 7pm. My shop is at 4019 > Sebastopol Rd. in Santa Rosa. If you haven't been there, please email > me for additional directions. > > --Steve > > > * (The "flea circus" is mine and Bruce L's motion-control learning > project. Bruce has built a framework about 2.5 feet across and 1.5 feet > tall with three towers. At the top of each tower is a stepper motor > that will drive a "drum" with thread wrapped around it. The three > threads will meet in the middle and support a small weight. By winding > and unwinding each spool, the weight can be moved in three dimensions. > > I've built a driver box with three EZ-Driver stepper-motor drivers, > three limit=sense lines, and a 25vdc power supply; and I'm building a > control box with a joystick (for the x- and y-axes) and a pot (for the z > axis). > > Wednesday, we're going to hook this all together with an Arduino and try > to make it do something. Helpers, kibbitzers, torta-fetchers, and > people who just want to stand around and talk are all welcome.) > ........................................................................ > .........dorkbot: people doing strange things with electricity.......... > ..........................http://dorkbot.org............................ > ........................................................................ > > From steve at chalem.com Tue Mar 18 16:31:38 2008 From: steve at chalem.com (Steve Chalem) Date: Tue Mar 18 16:30:42 2008 Subject: [dorkbotsebastopol-blabber] Sebastopol Dorkbot Build Meetingthis Week In-Reply-To: Message-ID: <3606B5BAD467A349AC94B0D05164DBD603C6DA2E@EXVBE014-13.exch014.msoutlookonline.net> I'm going to want to pick up some food & beverage for the Wed night meeting. Offhand I know of good Mexican and Thai near my place. -----Original Message----- From: dorkbotsebastopol-blabber-bounces@music.columbia.edu [mailto:dorkbotsebastopol-blabber-bounces@music.columbia.edu] On Behalf Of bsilva Sent: Monday, March 17, 2008 2:00 PM To: A discussion list for dorkbot-sebastopol Cc: dorkbotsebastopol-blabber@dorkbot.org Subject: Re: [dorkbotsebastopol-blabber] Sebastopol Dorkbot Build Meetingthis Week To all: Any opinions on Beer/Sodas/Pizza/Chinese/etc? Brad On Mon, 17 Mar 2008, Steve Chalem wrote: > We'll be meeting this week at my shop to start integrating the flea > circus*. Doors open at 6pm, meeting starts at 7pm. My shop is at > 4019 Sebastopol Rd. in Santa Rosa. If you haven't been there, please > email me for additional directions. > > --Steve > > > * (The "flea circus" is mine and Bruce L's motion-control learning > project. Bruce has built a framework about 2.5 feet across and 1.5 > feet tall with three towers. At the top of each tower is a stepper > motor that will drive a "drum" with thread wrapped around it. The > three threads will meet in the middle and support a small weight. By > winding and unwinding each spool, the weight can be moved in three dimensions. > > I've built a driver box with three EZ-Driver stepper-motor drivers, > three limit=sense lines, and a 25vdc power supply; and I'm building a > control box with a joystick (for the x- and y-axes) and a pot (for the > z axis). > > Wednesday, we're going to hook this all together with an Arduino and > try to make it do something. Helpers, kibbitzers, torta-fetchers, and > people who just want to stand around and talk are all welcome.) > ........................................................................ > .........dorkbot: people doing strange things with electricity.......... > ..........................http://dorkbot.org............................ > ........................................................................ > > ........................................................................ .........dorkbot: people doing strange things with electricity.......... ..........................http://dorkbot.org............................ ........................................................................ From steve at chalem.com Sun Mar 23 16:21:45 2008 From: steve at chalem.com (Steve Chalem) Date: Sun Mar 23 16:22:05 2008 Subject: [dorkbotsebastopol-blabber] Stepper annoyances Message-ID: <3606B5BAD467A349AC94B0D05164DBD6012530@EXVBE014-13.exch014.msoutlookonline.net> Brad, I did some more tests, this time with an ezdriver connected *directly* to the arduino (no ribbon cable); the "wall-wart" 12v power supply; short, direct wiring between the ezdriver and the motor, and a solid ground connection between the motor/driver circuit and the arduino. Result: same as before! The .4A vexta (or whatever) motor turns back and forth once the amp-limit trim pot is fine-tuned, but on closer examination is skipping a lot of steps. The little epson motor just flutters. Our hypothesis that the problems are caused by 60hz noise reaching the "direction" pin still makes sense, although of course i can't confirm the presense of the noise without an oscilliscope. BUT, I've done everything we discussed to eliminate noise and saw no change in behavior. One addl data point: the only time I've actually witnessed an ezdriver operating a motor properly was when you had one connected to a bitwhacker. I've never actually seen one work with an arduino. I do know people are using this combination successfully. --Steve -------------- next part -------------- An HTML attachment was scrubbed... URL: http://music.columbia.edu/pipermail/dorkbotsebastopol-blabber/attachments/20080323/4f300367/attachment.html From bsilva at sonic.net Sun Mar 23 18:57:55 2008 From: bsilva at sonic.net (bsilva) Date: Sun Mar 23 18:58:25 2008 Subject: [dorkbotsebastopol-blabber] Re: Stepper annoyances In-Reply-To: <3606B5BAD467A349AC94B0D05164DBD6012530@EXVBE014-13.exch014.msoutlookonline.net> References: <3606B5BAD467A349AC94B0D05164DBD6012530@EXVBE014-13.exch014.msoutlookonline.net> Message-ID: I've been busy with Family stuff this weekend, so I've not had much time to try and reproduce the issue. I did dig through my box of steppers yesterday and found an epson with a similar mechanical design to the small ones you're using, so hopefuly tonight I can give that a try (I'm at an Easter dinner at the moment). Meanwhile, I'll put my scope back in the truck and see if we can find a time where we can both be your shop some evening this week. Or, perhaps some morning? What time do you get going in the morning? Later, Brad On Sun, 23 Mar 2008, Steve Chalem wrote: > Brad, > > I did some more tests, this time with an ezdriver connected *directly* to the arduino (no ribbon cable); the "wall-wart" 12v power supply; short, direct wiring between the ezdriver and the motor, and a solid ground connection between the motor/driver circuit and the arduino. > > Result: same as before! The .4A vexta (or whatever) motor turns back and forth once the amp-limit trim pot is fine-tuned, but on closer examination is skipping a lot of steps. The little epson motor just flutters. > > Our hypothesis that the problems are caused by 60hz noise reaching the "direction" pin still makes sense, although of course i can't confirm the presense of the noise without an oscilliscope. BUT, I've done everything we discussed to eliminate noise and saw no change in behavior. > > One addl data point: the only time I've actually witnessed an ezdriver operating a motor properly was when you had one connected to a bitwhacker. I've never actually seen one work with an arduino. I do know people are using this combination successfully. > > --Steve > From bsilva at sonic.net Mon Mar 24 00:29:14 2008 From: bsilva at sonic.net (bsilva) Date: Mon Mar 24 00:30:07 2008 Subject: [dorkbotsebastopol-blabber] Re: Stepper annoyances In-Reply-To: <3606B5BAD467A349AC94B0D05164DBD6012530@EXVBE014-13.exch014.msoutlookonline.net> References: <3606B5BAD467A349AC94B0D05164DBD6012530@EXVBE014-13.exch014.msoutlookonline.net> Message-ID: Well, I have a small epson (looks like two pancake coils sandwiched together (Hmmm.. Two food metaphors in one sentence, must be hungry)) and it's working fine. One difference, it's a six wire unit and yours is a four. I think the next step is to bring my test setup to your shop along with my scope and see what's different. I'm not sure I can do this week though, I have some major paperwork to do along side my normal job. I'll try though, I'm very curious about this. Brad P.S. Does the stepper exhibt the same symptoms immediately after powering on the ezstepper? i.e. Could we looking at the ezstepper going into thermal shutdown? Two suggestions; try a bigger heatsink and try turning the current limit pot clockwise. I've taken a real close look at the pot on my unit and viewed from the side you can see where a top and bottom piece of metal come together. It appears that the wiper is directly opposite this fold. It also appears that if the wiper is pointed at the "adj" marking the current should be at its minimum. That's assuming that your wiper is the same type as mine. Hmm... too many vague statements in this paragraph. I think I'm going to write the guys at Sparkfun and ask them to put a pot on this thing where it's possible to have a clue as to how it's set. On Sun, 23 Mar 2008, Steve Chalem wrote: > Brad, > > I did some more tests, this time with an ezdriver connected *directly* to the arduino (no ribbon cable); the "wall-wart" 12v power supply; short, direct wiring between the ezdriver and the motor, and a solid ground connection between the motor/driver circuit and the arduino. > > Result: same as before! The .4A vexta (or whatever) motor turns back and forth once the amp-limit trim pot is fine-tuned, but on closer examination is skipping a lot of steps. The little epson motor just flutters. > > Our hypothesis that the problems are caused by 60hz noise reaching the "direction" pin still makes sense, although of course i can't confirm the presense of the noise without an oscilliscope. BUT, I've done everything we discussed to eliminate noise and saw no change in behavior. > > One addl data point: the only time I've actually witnessed an ezdriver operating a motor properly was when you had one connected to a bitwhacker. I've never actually seen one work with an arduino. I do know people are using this combination successfully. > > --Steve > From steve at chalem.com Mon Mar 24 13:16:36 2008 From: steve at chalem.com (Steve Chalem) Date: Mon Mar 24 13:20:22 2008 Subject: [dorkbotsebastopol-blabber] Stepper annoyances References: <3606B5BAD467A349AC94B0D05164DBD6012530@EXVBE014-13.exch014.msoutlookonline.net> <3606B5BAD467A349AC94B0D05164DBD6012532@EXVBE014-13.exch014.msoutlookonline.net> Message-ID: <3606B5BAD467A349AC94B0D05164DBD6012533@EXVBE014-13.exch014.msoutlookonline.net> Brad, I'll try both motors with a just-powered-up ezdriver and let you know what happens. I'm in Oakland for a few days, so I won't be able to try it until Thursday or so. (I'm also not expecting to make the Wed. nite meeting this week.) Re next steps, I'd like to compare your setup with mine and it'd be great to have your help diagnosing this. Friday or next weekend should be good, or one day the following week. Meanwhile I'll try the above and also a bigger heat sink and twiddling the pot. --Steve ________________________________ From: bsilva [mailto:bsilva@sonic.net] Sent: Sun 3/23/2008 9:29 PM To: Steve Chalem Cc: dorkbotsebastopol-blabber@dorkbot.org Subject: Re: Stepper annoyances Well, I have a small epson (looks like two pancake coils sandwiched together (Hmmm.. Two food metaphors in one sentence, must be hungry)) and it's working fine. One difference, it's a six wire unit and yours is a four. I think the next step is to bring my test setup to your shop along with my scope and see what's different. I'm not sure I can do this week though, I have some major paperwork to do along side my normal job. I'll try though, I'm very curious about this. Brad P.S. Does the stepper exhibt the same symptoms immediately after powering on the ezstepper? i.e. Could we looking at the ezstepper going into thermal shutdown? Two suggestions; try a bigger heatsink and try turning the current limit pot clockwise. I've taken a real close look at the pot on my unit and viewed from the side you can see where a top and bottom piece of metal come together. It appears that the wiper is directly opposite this fold. It also appears that if the wiper is pointed at the "adj" marking the current should be at its minimum. That's assuming that your wiper is the same type as mine. Hmm... too many vague statements in this paragraph. I think I'm going to write the guys at Sparkfun and ask them to put a pot on this thing where it's possible to have a clue as to how it's set. On Sun, 23 Mar 2008, Steve Chalem wrote: > Brad, > > I did some more tests, this time with an ezdriver connected *directly* to the arduino (no ribbon cable); the "wall-wart" 12v power supply; short, direct wiring between the ezdriver and the motor, and a solid ground connection between the motor/driver circuit and the arduino. > > Result: same as before! The .4A vexta (or whatever) motor turns back and forth once the amp-limit trim pot is fine-tuned, but on closer examination is skipping a lot of steps. The little epson motor just flutters. > > Our hypothesis that the problems are caused by 60hz noise reaching the "direction" pin still makes sense, although of course i can't confirm the presense of the noise without an oscilliscope. BUT, I've done everything we discussed to eliminate noise and saw no change in behavior. > > One addl data point: the only time I've actually witnessed an ezdriver operating a motor properly was when you had one connected to a bitwhacker. I've never actually seen one work with an arduino. I do know people are using this combination successfully. > > --Steve > -------------- next part -------------- An HTML attachment was scrubbed... URL: http://music.columbia.edu/pipermail/dorkbotsebastopol-blabber/attachments/20080324/24f06c1d/attachment.html