Re: [Emc-users] Watchdog Sizing
S, Erik Christiansen piše: > On Wed, Dec 08, 2010 at 07:00:27PM -0800, Kirk Wallace wrote: >> Thank you John. I really appreciate the time you take to help. Using >> your information above, I redrew the schematic, which I'll revise as I >> go. It's at the bottom of the page here: >> http://www.wallacecompany.com/machine_shop/Shizuoka/ > Kirk, apropos the comment there that it's not quite clear how the charge > pump works, does it help at all, just for a more physical visualisation, > to imagine C1 as a liquid pump's cylinder, with the top plate being the > piston, driven up and down by IC1A, and D1& D2 as fluid non-return > valves? C2 is the reservoir into which this pump is pumping "positive > charge" [1]. If C1 isn't driven up and down, charge isn't going to flow > out of ground to C2, and its charge decays through R2. > > The only change I'd make to the circuit is to connect R1 to +5v, so that > the default state of IC1A output is low. That is because a capacitor is > more likely than not to go short circuit in the rare event that it > fails. That would give a false "OK", in the absence of input. (It'll > work fine as-is if there's no component failure.) > > Dunno if my attempt to paint a picture really ended up less laboured, > and more descriptive that going through it in purely electronic terms, > but we can always do that if this attempt isn't as clear as it should > be. > > Erik Maybe you have just too little current in output. So just route unused gates paralel to last one. (pins 1,3,5,9 together and pins 2,4,6,8 together) -- This SF Dev2Dev email is sponsored by: WikiLeaks The End of the Free Internet http://p.sf.net/sfu/therealnews-com ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Expansion of EMC
Hallo, 1. EMC appeals to the hobbyists. It has a good basic structure inherited from NIST but lately lots of things have been happening that are not so well structured and documented. 2. Here and there it gets a bit stale already. 3. The user interface needs a lot of critical thinking still, to bring it up to scratch. Have a good look at the latest FANUCs for instance. 4. So to me it is a perfect solution for specials. But it will need a LOT of work to make i appealing to the mass market. In fact I do heavy evangelizing in the workplace, but the resistance is unbelievable. 5. So personally I will not invest in such a company. But your mileage may differ. 6. Where money comes in through the frontdoor, trust leaves through the backdoor; and the most important thing is NOT going to happen anytime real soon, because now we are argueing. 7. So I propose we rather consentrate on enjoyment and see if we cannot clean up a few things in the software here and there. Perhaps see if we can make a professional version that costs a bit more in switches etc, but that will be very presentable. Regards, Jan de Kruyf. On Thu, Dec 9, 2010 at 7:50 AM, Edward Bernard wrote: > I'm surprised there were no comments on this. I'm wondering how such a > venture > could effect our beloved software. > > > > - Original Message > From: Anonymous Investor > To: emc-users@lists.sourceforge.net > Sent: Wed, December 8, 2010 9:10:13 AM > Subject: [Emc-users] Expansion of EMC > > *Business Opportunity related to EMC2* > > EMC2 may be well written CNC control software, but it does not appear to be > making progress entering mainstream applications. We believe that the > largest impediment to success is the lack of a full scope supplier. We > feel > that the mainstream machine builder community, meaning hobby, professional, > and OEM, remains outside the open source community. Furthermore, we feel > that the solution is not to try and bring machine builders into the open > source community, but rather to bring complete solutions to machine > builders. We propose the creation of a company which delivers EMC based > solutions, essentially the Red Hat of CNC. To that end, we will finance > such a company. > > > > *Perspective:* > > There are quite a few hobby oriented suppliers, based on Mach3, TurboCAD, > and other solutions, which offer everything including ballscrews, motors, > drivers, and circuit boards. These companies serve their customers well, > but they do not come up to the level of professionalism that is necessary > to > attract serious commercial machine builders. > > > > There are mid-level suppliers, such as Flashcut, CamSoft, or Centroid, > which > offer reasonable value but cannot provide the security, vendor > independence, > or continuity of supply, which would be available with a more open > technology. Of course the 800 lb gorilla is Fanuc, having sold 2.2 > million > control systems. While offering the ultimate in performance, Fanuc > solutions come with minimum vendor independence and dismal ROI for those > only needed mid-level performance. > > > > We believe a full service, professional grade supplier, offering complete > control systems solutions, can be an effective competitor and is sorely > needed by all levels of machine builders. We are not proposing open source > hardware, but rather combining open source software with support and > conventional industrial components to develop full spectrum solutions. This > is not a matter of welcoming machine builders into the open source > community; rather it is an issue of bringing the resources and value of > open > source to the market, offering attractive ROI to both customers and > investor. > > > > *Details and How to Proceed:* > > We are looking to invest in a start-up business which meets the general > goals as outlined above. We will provide the majority of capital and > mentoring as needed. We will not participate in, nor attempt to control, > the day to day activities of the business. If you want this to be your > start-up business, submit a business plan to the email of Anonymous > Investor > at the address [backgroundpartner at gmail.com]. All submissions will > remain confidential. There are many resources available for guidance on > the > development of a business plan, Google it. There is no specific timeline > for this venture, but we will keep it open for at least 2 months. This is > not a contest; it’s an investment and a partnership. A credible plan may > be > reviewed with suggestions for improvement. We have limited time for dialog > and are unlikely to answer email from those with idle curiosity. > > > > *Anti-Spam and Scam Issues:* > > The legitimacy of this opportunity should speak for itself. This offer is > only going out to the EMC email list and at no time will we ask for money, > deposits, or personal financial information. Our anonymity will be removed > for those whose negotiations appear credible an
Re: [Emc-users] Expansion of EMC
I'm surprised there were no comments on this. I'm wondering how such a venture could effect our beloved software. - Original Message From: Anonymous Investor To: emc-users@lists.sourceforge.net Sent: Wed, December 8, 2010 9:10:13 AM Subject: [Emc-users] Expansion of EMC *Business Opportunity related to EMC2* EMC2 may be well written CNC control software, but it does not appear to be making progress entering mainstream applications. We believe that the largest impediment to success is the lack of a full scope supplier. We feel that the mainstream machine builder community, meaning hobby, professional, and OEM, remains outside the open source community. Furthermore, we feel that the solution is not to try and bring machine builders into the open source community, but rather to bring complete solutions to machine builders. We propose the creation of a company which delivers EMC based solutions, essentially the Red Hat of CNC. To that end, we will finance such a company. *Perspective:* There are quite a few hobby oriented suppliers, based on Mach3, TurboCAD, and other solutions, which offer everything including ballscrews, motors, drivers, and circuit boards. These companies serve their customers well, but they do not come up to the level of professionalism that is necessary to attract serious commercial machine builders. There are mid-level suppliers, such as Flashcut, CamSoft, or Centroid, which offer reasonable value but cannot provide the security, vendor independence, or continuity of supply, which would be available with a more open technology. Of course the 800 lb gorilla is Fanuc, having sold 2.2 million control systems. While offering the ultimate in performance, Fanuc solutions come with minimum vendor independence and dismal ROI for those only needed mid-level performance. We believe a full service, professional grade supplier, offering complete control systems solutions, can be an effective competitor and is sorely needed by all levels of machine builders. We are not proposing open source hardware, but rather combining open source software with support and conventional industrial components to develop full spectrum solutions. This is not a matter of welcoming machine builders into the open source community; rather it is an issue of bringing the resources and value of open source to the market, offering attractive ROI to both customers and investor. *Details and How to Proceed:* We are looking to invest in a start-up business which meets the general goals as outlined above. We will provide the majority of capital and mentoring as needed. We will not participate in, nor attempt to control, the day to day activities of the business. If you want this to be your start-up business, submit a business plan to the email of Anonymous Investor at the address [backgroundpartner at gmail.com]. All submissions will remain confidential. There are many resources available for guidance on the development of a business plan, Google it. There is no specific timeline for this venture, but we will keep it open for at least 2 months. This is not a contest; it’s an investment and a partnership. A credible plan may be reviewed with suggestions for improvement. We have limited time for dialog and are unlikely to answer email from those with idle curiosity. *Anti-Spam and Scam Issues:* The legitimacy of this opportunity should speak for itself. This offer is only going out to the EMC email list and at no time will we ask for money, deposits, or personal financial information. Our anonymity will be removed for those whose negotiations appear credible and who sign non-disclosure agreement. Yours, Anonymous Investor -- What happens now with your Lotus Notes apps - do you make another costly upgrade, or settle for being marooned without product support? Time to move off Lotus Notes and onto the cloud with Force.com, apps are easier to build, use, and manage than apps on traditional platforms. Sign up for the Lotus Notes Migration Kit to learn more. http://p.sf.net/sfu/salesforce-d2d ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- This SF Dev2Dev email is sponsored by: WikiLeaks The End of the Free Internet http://p.sf.net/sfu/therealnews-com ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Watchdog Sizing
On Wed, Dec 08, 2010 at 07:00:27PM -0800, Kirk Wallace wrote: > > Thank you John. I really appreciate the time you take to help. Using > your information above, I redrew the schematic, which I'll revise as I > go. It's at the bottom of the page here: > http://www.wallacecompany.com/machine_shop/Shizuoka/ Kirk, apropos the comment there that it's not quite clear how the charge pump works, does it help at all, just for a more physical visualisation, to imagine C1 as a liquid pump's cylinder, with the top plate being the piston, driven up and down by IC1A, and D1 & D2 as fluid non-return valves? C2 is the reservoir into which this pump is pumping "positive charge" [1]. If C1 isn't driven up and down, charge isn't going to flow out of ground to C2, and its charge decays through R2. The only change I'd make to the circuit is to connect R1 to +5v, so that the default state of IC1A output is low. That is because a capacitor is more likely than not to go short circuit in the rare event that it fails. That would give a false "OK", in the absence of input. (It'll work fine as-is if there's no component failure.) Dunno if my attempt to paint a picture really ended up less laboured, and more descriptive that going through it in purely electronic terms, but we can always do that if this attempt isn't as clear as it should be. Erik [1] While it's electrons going the other way really, it's more convenient to discuss "positive charge" when talking about accumulating a positive voltage. -- This SF Dev2Dev email is sponsored by: WikiLeaks The End of the Free Internet http://p.sf.net/sfu/therealnews-com ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Watchdog Sizing
On Wed, 2010-12-08 at 15:53 -0500, John Kasunich wrote: ... snip > It isn't that complicated. A 0.1uF output cap (C3) will work for > the frequencies and delays we are interested in with EMC. Choose > the output time constant and pick the R5 accordingly: R5 = T / C3. ... snip Thank you John. I really appreciate the time you take to help. Using your information above, I redrew the schematic, which I'll revise as I go. It's at the bottom of the page here: http://www.wallacecompany.com/machine_shop/Shizuoka/ -- Kirk Wallace http://www.wallacecompany.com/machine_shop/ http://www.wallacecompany.com/E45/index.html California, USA -- This SF Dev2Dev email is sponsored by: WikiLeaks The End of the Free Internet http://p.sf.net/sfu/therealnews-com ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
[Emc-users] Tool change challenge (Advanced Configuration forum)
Still undecided as how to resolve the tool change challenge. I am deliberating on two solutions Option #1 Use a DC servomotor like a Homeshops 850 oz-in and a drive like the Gecko 320. This will allow positioning the spindle with plenty of accuracy and spin my cutter at around 3,000 RPM. Since the Gecko drive has a step and direction input I hope to be able to reconfigure the HAL code to use A step generator to control the spindle rather than the PWM generator. The one downside is less horsepower than I would like. Using the servomotors I have seen with a gecko 320 delivers a shaft power output less than 1HP, I would prefer 2HP. I continue looking for alternative motors and drives that could provide more HP. Suggestions welcome! Option #2 Use a Variable frequency drive like a Durapulse GS3 this has A flux vector mode (as suggested by Andy also thanks for the video clip) and a inverter grade induction motor. I have talked with techs that work for vendors of these types of drives and have received conflicting opinions as to whether I could position the spindle with enough accuracy for my tool change. I suspect this would work but it could also be an expensive disappointment! It would be very helpful if I could locate some one who has real world experience using these new variable frequency drives, particularly if they are using EMC2 also. -- This SF Dev2Dev email is sponsored by: WikiLeaks The End of the Free Internet http://p.sf.net/sfu/therealnews-com ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Watchdog Sizing
On Wed, 08 Dec 2010 12:15 -0800, "Kirk Wallace" wrote: > This is what I have from the last time I played with the above type of > circuit (sourced by JK?): > http://www.wallacecompany.com/machine_shop/Shizuoka/watchdog-1b.png > > It worked on my breadboard but didn't work when I transferred it to a > PCB. Other things came up and I didn't get back to fixing it. A few things come to mind looking at that circuit. 1) Using a schmidt input gate (the 74LS14) is good, but I would use a CMOS input gate like a 74HC14. That way the loading on the pump can be ignored, and you can use much larger resistors and smaller caps. 2) The caps seem very large. When I see microfarads, I think electro- lytics, which have sloppy tolerances, high leakage current, and are polarized. This is the kind of circuit that wants to use film or ceramic caps. I would design it with the output cap (C3) as 0.1uF or maybe 1uF if I had that value laying around in ceramic or film. 3) The pump caps (C1 and C2) should be 10 to 100 times smaller than the output cap. You don't want a single pulse on the input to be able to transfer a significant amount of charge to the output - it should take many pulses to charge the output. 4) The time constant of the load resistor (R5) and the output cap (C3) is what determines how long it will take to drop out after the input stops pulsing. It should be much longer than the input period, but short enough to be safe. For a 1kHz input, I'd probably aim for 100mS. With a 0.1uF output cap, that is a 1 meg R5... hence the desire for a CMOS input. 5) I worry a bit about the extra stage. The classic charge pump circuit has only two diodes and one pump cap. Imagine the circuit as drawn, with IC1C and C2 removed, and D3 shorted. That version produces an output voltage that is always a little less than the output swing of IC1F minus two diode drops, which ensures that the input to IC1A is always lower than it's power supply rail. The version shown, with three diodes and two pump caps, can produce an output that approaches twice the IC1 output swing minus three diode drops. That exceeds the input rating of IC1A. The above statements are based on CMOS logic, where output swings are nearly rail-to-rail, and inputs are high impedance. With the LS family logic, you probably get a lot less output but the circuit is much harder to analyze in detail. > The analog method is probably more practical, but the digital > solution may be viable too. Of course there are many ways to solve the problem. > It may be possible to do this with very few > components (Vregulator, cap or two, ATtiny2313), at the same cost and > have more flexibility (wide charge pump frequency range, learning mode, > different fault responses, complex WD signal). The parts count may be similar, but the complexity is not. All of those features add complexity. The more complex something is, the more likely it is to contain un-anticipated failure modes, or just plain outright bugs. ANY software or firmware dramatically increases the complexity. > I'm still playing with > it, and for me the programming hurdle is pretty high, so who knows what > the result might be. > > For someone needing a one-off circuit for a particular machine, the > analog circuit above is probably the quickest solution. Especially, if > there were(was?) a widget or cloud app that one could use to calculate > the part values and model performance (Spice? but that is another > unfilled time sink). It isn't that complicated. A 0.1uF output cap (C3) will work for the frequencies and delays we are interested in with EMC. Choose the output time constant and pick the R5 accordingly: R5 = T / C3. The pump cap(s) C1 (and C2, if using the two stage design) should be no more than 1/10 of C3, so 0.01uF (10nF) maximum. If you make them too small, you won't get enough output voltage. I'd probably start with 1nF, and increase if needed. The higher the charge pump frequency in relation to the output time constant, the smaller the pump caps can be. If you are pumping at 1kHz and the output time constant is 100mS, 1nF might be too small. If pumping at 10kHz, it should work fine. I guess in the end it depends on what you are familiar with. I can design the analog circuit in a few minutes, build a perfboard version in 20 minutes, and test it within an hour of starting. It would take me several times that long to get a microcontroller development system running to the point of being able to write and execute even the simplest program. Other people probably have the exact opposite situation. John -- John Kasunich jmkasun...@fastmail.fm -- This SF Dev2Dev email is sponsored by: WikiLeaks The End of the Free Internet http://p.sf.net/sfu/therealnews-com ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lis
Re: [Emc-users] Watchdog Sizing
On Wed, 2010-12-08 at 13:53 -0500, John Kasunich wrote: > On 4 December 2010 00:46, Kirk Wallace > wrote: > > > > I'm working on using an ATtiny to watch EMC2's charge pump. > > Why not use a charge pump circuit to watch the charge pump signal? > > That is what it was designed for, and is probably the most fail-safe > solution. The timeout period is set by the capacitors and resistors > you choose, and can't get accidentally changed or disabled. > > A charge pump circuit consists of two diodes, one small capacitor > (a few hundred pF or a few nF), one medium capacitor (a few tens > of nF), and a resistor. Also needed is something to look at its > output and turn off the dangerous stuff if the output drops too low. > That can be as simple as a transistor driving a relay coil, or you > could use a schmidt trigger input logic gate followed by whatever > you need to drive. This is what I have from the last time I played with the above type of circuit (sourced by JK?): http://www.wallacecompany.com/machine_shop/Shizuoka/watchdog-1b.png It worked on my breadboard but didn't work when I transferred it to a PCB. Other things came up and I didn't get back to fixing it. > No microcontroller, no programming, no configuration, no bits. > Analog lives! > > John Kasunich The analog method is probably more practical, but the digital solution may be viable too. It may be possible to do this with very few components (Vregulator, cap or two, ATtiny2313), at the same cost and have more flexibility (wide charge pump frequency range, learning mode, different fault responses, complex WD signal). I'm still playing with it, and for me the programming hurdle is pretty high, so who knows what the result might be. For someone needing a one-off circuit for a particular machine, the analog circuit above is probably the quickest solution. Especially, if there were(was?) a widget or cloud app that one could use to calculate the part values and model performance (Spice? but that is another unfilled time sink). -- Kirk Wallace http://www.wallacecompany.com/machine_shop/ http://www.wallacecompany.com/E45/index.html California, USA -- This SF Dev2Dev email is sponsored by: WikiLeaks The End of the Free Internet http://p.sf.net/sfu/therealnews-com ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Watchdog Sizing
S, Roland Jollivet piše: > I was wondering, can a fault ever occur with EMC where the frequency of the > charge pump frequency increases?? This would keep the charge pump detector > 'up', but a uP would detect an error condition. > > Regards > Roland > NE567 can solve that too... -- This SF Dev2Dev email is sponsored by: WikiLeaks The End of the Free Internet http://p.sf.net/sfu/therealnews-com ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Watchdog Sizing
Roland Jollivet wrote: > I was wondering, can a fault ever occur with EMC where the frequency of the > charge pump frequency increases?? This would keep the charge pump detector > 'up', but a uP would detect an error condition. > It seems unlikely. The most likely effect of a software problem will be a crash. This would most likely cause pulses to stop, not to speed up. There is now a watchdog HAL component, which can monitor heartbeats from other modules (not that any other modules currently output such a heartbeat), and which will disable its output if any heartbeat stops. This would cause situations where some userspace modules die, but the realtime kernel keeps running, to still cause a fault. (As it is, if RT is running, the heartbeat will be output, regardless of whether e.g. the GUI has crashed) - Steve -- This SF Dev2Dev email is sponsored by: WikiLeaks The End of the Free Internet http://p.sf.net/sfu/therealnews-com ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Watchdog Sizing
actually - really? we could get it - just paying for your time? thanks sam On 12/8/2010 1:25 PM, Roland Jollivet wrote: > I was wondering, can a fault ever occur with EMC where the frequency of the > charge pump frequency increases?? This would keep the charge pump detector > 'up', but a uP would detect an error condition. > > Regards > Roland > > > On 8 December 2010 20:53, John Kasunich wrote: > >> On 4 December 2010 00:46, Kirk Wallace >> wrote: >>> I'm working on using an ATtiny to watch EMC2's charge pump. >> Why not use a charge pump circuit to watch the charge pump signal? >> >> That is what it was designed for, and is probably the most fail-safe >> solution. The timeout period is set by the capacitors and resistors >> you choose, and can't get accidentally changed or disabled. >> >> A charge pump circuit consists of two diodes, one small capacitor >> (a few hundred pF or a few nF), one medium capacitor (a few tens >> of nF), and a resistor. Also needed is something to look at its >> output and turn off the dangerous stuff if the output drops too low. >> That can be as simple as a transistor driving a relay coil, or you >> could use a schmidt trigger input logic gate followed by whatever >> you need to drive. >> >> No microcontroller, no programming, no configuration, no bits. >> Analog lives! >> >> John Kasunich >> >> -- >> John Kasunich >> jmkasun...@fastmail.fm >> >> >> >> -- >> This SF Dev2Dev email is sponsored by: >> >> WikiLeaks The End of the Free Internet >> http://p.sf.net/sfu/therealnews-com >> ___ >> Emc-users mailing list >> Emc-users@lists.sourceforge.net >> https://lists.sourceforge.net/lists/listinfo/emc-users >> > -- > This SF Dev2Dev email is sponsored by: > > WikiLeaks The End of the Free Internet > http://p.sf.net/sfu/therealnews-com > ___ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > -- This SF Dev2Dev email is sponsored by: WikiLeaks The End of the Free Internet http://p.sf.net/sfu/therealnews-com ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Watchdog Sizing
I was wondering, can a fault ever occur with EMC where the frequency of the charge pump frequency increases?? This would keep the charge pump detector 'up', but a uP would detect an error condition. Regards Roland On 8 December 2010 20:53, John Kasunich wrote: > On 4 December 2010 00:46, Kirk Wallace > wrote: > > > > I'm working on using an ATtiny to watch EMC2's charge pump. > > Why not use a charge pump circuit to watch the charge pump signal? > > That is what it was designed for, and is probably the most fail-safe > solution. The timeout period is set by the capacitors and resistors > you choose, and can't get accidentally changed or disabled. > > A charge pump circuit consists of two diodes, one small capacitor > (a few hundred pF or a few nF), one medium capacitor (a few tens > of nF), and a resistor. Also needed is something to look at its > output and turn off the dangerous stuff if the output drops too low. > That can be as simple as a transistor driving a relay coil, or you > could use a schmidt trigger input logic gate followed by whatever > you need to drive. > > No microcontroller, no programming, no configuration, no bits. > Analog lives! > > John Kasunich > > -- > John Kasunich > jmkasun...@fastmail.fm > > > > -- > This SF Dev2Dev email is sponsored by: > > WikiLeaks The End of the Free Internet > http://p.sf.net/sfu/therealnews-com > ___ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > -- This SF Dev2Dev email is sponsored by: WikiLeaks The End of the Free Internet http://p.sf.net/sfu/therealnews-com ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Watchdog Sizing
On 4 December 2010 00:46, Kirk Wallace wrote: > > I'm working on using an ATtiny to watch EMC2's charge pump. Why not use a charge pump circuit to watch the charge pump signal? That is what it was designed for, and is probably the most fail-safe solution. The timeout period is set by the capacitors and resistors you choose, and can't get accidentally changed or disabled. A charge pump circuit consists of two diodes, one small capacitor (a few hundred pF or a few nF), one medium capacitor (a few tens of nF), and a resistor. Also needed is something to look at its output and turn off the dangerous stuff if the output drops too low. That can be as simple as a transistor driving a relay coil, or you could use a schmidt trigger input logic gate followed by whatever you need to drive. No microcontroller, no programming, no configuration, no bits. Analog lives! John Kasunich -- John Kasunich jmkasun...@fastmail.fm -- This SF Dev2Dev email is sponsored by: WikiLeaks The End of the Free Internet http://p.sf.net/sfu/therealnews-com ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] EMC2 and 4th axis in milling: specifying speed and angular velocity?
On Wed, Dec 08, 2010 at 09:00:57AM -0500, Stephen Wille Padnos wrote: > This is how the manual describes combined linear and rotary motion: "If > any of XYZ are moving, F is in units per minute in the XYZ cartesian > system, and all other axes (UVWABC) move so as to start and stop in > coordinated fashion" Because this can be confusing if you then switch between combined and angular-only moves, also consider the hint in "G Code Best Practices" http://www.linuxcnc.org/docs/html/gcode_overview.html#r3_8 which says Because the meaning of an F-word in feed-per-minute mode varies depending on which axes are commanded to move, and because the amount of material removed does not depend only on the feed rate, it may be easier to use G93 inverse time feed mode to achieve the desired material removal rate. -- This SF Dev2Dev email is sponsored by: WikiLeaks The End of the Free Internet http://p.sf.net/sfu/therealnews-com ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] fixed jog distance
On 12/07/2010 09:30 PM, Tom Easterday wrote: > I want to be able to jog my machine a fixed small distance (.001") at a press > of a button/arrow key/joystick. Currently my joystick or arrow keys moves > continuously, which is fine in some cases and not in others. Is there a way > to enable, say holding down button 4, on my joystick causes each jog to be a > fixed distance? > Sure! When axis.N.jog-enable is true, the motion controller responds to changes in the value of axis.N.jog-counts by jogging the axis the distance specified by axis.N.jog-scale. So you might try something like this: * Set .jog-scale (on all axes) to +0.001 or -0.001 depending on whether a plus-direction or minus-direction button is pushed. * Set .jog-enable true on the one axis corresponding to the jog button pushed. * Use an encoder component in counter-mode to make a counter that increments whenever any of the "jog a fixed amount" buttons is pushed. Untested! But that's where I would start. -- Sebastian Kuzminsky -- This SF Dev2Dev email is sponsored by: WikiLeaks The End of the Free Internet http://p.sf.net/sfu/therealnews-com ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] OT: Hall 10Bit 360° Programmabl e Magnetic Rotary Encoder
On Wed, 2010-12-08 at 15:56 +0200, Roland Jollivet wrote: > I have looked at these. The linearity is quite poor, see pg. 6 and 7 > It looks like you might be up to 10 counts out at any position with an > optimally placed magnet. > > Slotted encoders are usually out by a % of less than one count. > > The parameters will also change as the bearings wear over time. I think they > are great for something like a butterfly valve or accelerator pedal where > lots of discrete steps are required, but their relative accuracy is not > important. > > Regards > Roland I have played with a similar device, the AEAT6010: http://wallacecompany.com/machine_shop/EMC2/AEAT-6010/ My plan is to use it with my tool changer carousel as an absolute pocket encoder. This allows me to know the pocket position without going through an initializing motion to find an index on an incremental encoder. One issue, for an absolute encoder, is the data link to EMC2. There is only a digital bit input so far. My AEAT6010 application uses an SPI link for which I created a halcomponent that bit-bangs the serial bits into a few parallel port pins. http://wallacecompany.com/machine_shop/EMC2/AEAT-6010/ This can work well for a tool changer, but not for realtime motion control. I suspect anywhere a potentiometer can be used, these Hall sensors would be an appropriate replacement, plus there is no or less mechanical wear and dirt issues. Now if I would just get off my behind and finish the project, you could see it work. -- Kirk Wallace http://www.wallacecompany.com/machine_shop/ http://www.wallacecompany.com/E45/index.html California, USA -- This SF Dev2Dev email is sponsored by: WikiLeaks The End of the Free Internet http://p.sf.net/sfu/therealnews-com ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] EMC2 and 4th axis in milling: specifying speed and angular velocity?
Igor Chudov wrote: > > Let's say I wanted to mill a helical spiral. > > Can I use EMC2 to instruct the milling table to move along X at a > given velocity, while at the same time, the rotary table is turning > with another given angular rotational speed. You can't specify two different feedrates. The feedrate applies to the X motion, the A axis follows along so that it completes at the same time as the X move. So, you would code someting like : G01 X1 F50 Z-0.1 F5 X2.345 A360 F7.5 Z1 EMC computes feedrate based solely on the X distance, ignoring the contribution of the A rotation. Jon -- This SF Dev2Dev email is sponsored by: WikiLeaks The End of the Free Internet http://p.sf.net/sfu/therealnews-com ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Laser control
dambacher-retrofit.de wrote: > Hi Neil > > Am 07.12.2010 19:00, schrieb Neil Baylis: > >> What's the best strategy for controlling a laser? >> >> My machine uses 2 axes to move the laser optic to the right position. I've >> got this much working satisfactorily. Now I need to control the laser power. >> I was planning to use a 3rd axis for this, let's call it Z. >> >> My plan was to use the sign of the Z position to control the laser-enable >> signal, and the magnitude of the Z position to control the laser power. But >> maybe this is a stupid idea... I don't know. >> > > maybe you shold use the spindle controls for this, e.g. use S for laser power > and M3/M4/M5 for switching. > This way you could use normal cam to program your machine. > I believe that any change to spindle speed will cause a pause in the axis motion. I know any start/stop command (M03 -- M05) will do that. Anyway, I believe that spindle speed changes are not synchronized with the motion. Jon -- This SF Dev2Dev email is sponsored by: WikiLeaks The End of the Free Internet http://p.sf.net/sfu/therealnews-com ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Laser control
Neil, >> What's the best strategy for controlling a laser? My machine uses 2 axes to move the laser optic to the right position. I've got this much working satisfactorily. Now I need to control the laser power. I was planning to use a 3rd axis for this, let's call it Z. My plan was to use the sign of the Z position to control the laser-enable signal, and the magnitude of the Z position to control the laser power. But maybe this is a stupid idea... I don't know. << It is often a conundrum as to whether it is better to treat the laser as spindle or an axis. If you are doing cutting, it is more like a spindle, but if you are doing engraving it is more like an axis. In your case, making it an axis is probably the better choice. It has the advantage of being able to design in 3D and have it look like the intended engraving (also in 3D). At least that is the plan, but see below. >> For example, let's say I wanted to cut/burn a dashed line. It would be preferable if the optic could keep moving at a constant speed, and the beam would just turn on and off at the appropriate positions. Would I be able to do that if the beam was controlled by the Z axis position? << Yes, but with some limitations. Make sure you understand the consequences of section "3.1.4 Planning Moves" in the user manual (http://linuxcnc.org/docs/EMC2_User_Manual.pdf). If you have very small vector lengths and/or are running at high speed, the system will slow down as described in that section. One method of minimizing this is to, in the G-Code, use very small values for Z, then scale up to the range of the controlling output, be it an analog or pwm. Further there are timing limitations such as the servo period which is going to dictate how the maximum rate at which you can change the laser power. If your servo period is set to 1ms for example, then the quickest you will be able to adjust the laser power is 1ms. Further, the laser itself has a maximum rate at which the power can be changed, typically 5Khz (200 microseconds) or slower. Lasers used for high speed laser engraving will often simply gate the enable, thus turning the laser on and off, rather than adjust the laser power. >> This thing moves pretty fast.. maybe 25 to 30 inches per second, and I'm not sure if I'll be able to turn the beam on and off with enough precision. << 30 IPS with a 1ms servo loop means a maximum theoretical resolution of 30 thousandths. >> Later, I'll need to compensate for the linear velocity of the optic, so that it burns with less power when it is moving slowly. This will require computing the real-time velocity vector in x-y space and using that to control the laser power. << See Feedcomp: http://linuxcnc.org/docs/html/man/man9/feedcomp.9.html Regards, Eric -- This SF Dev2Dev email is sponsored by: WikiLeaks The End of the Free Internet http://p.sf.net/sfu/therealnews-com ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
[Emc-users] Expansion of EMC
*Business Opportunity related to EMC2* EMC2 may be well written CNC control software, but it does not appear to be making progress entering mainstream applications. We believe that the largest impediment to success is the lack of a full scope supplier. We feel that the mainstream machine builder community, meaning hobby, professional, and OEM, remains outside the open source community. Furthermore, we feel that the solution is not to try and bring machine builders into the open source community, but rather to bring complete solutions to machine builders. We propose the creation of a company which delivers EMC based solutions, essentially the Red Hat of CNC. To that end, we will finance such a company. *Perspective:* There are quite a few hobby oriented suppliers, based on Mach3, TurboCAD, and other solutions, which offer everything including ballscrews, motors, drivers, and circuit boards. These companies serve their customers well, but they do not come up to the level of professionalism that is necessary to attract serious commercial machine builders. There are mid-level suppliers, such as Flashcut, CamSoft, or Centroid, which offer reasonable value but cannot provide the security, vendor independence, or continuity of supply, which would be available with a more open technology. Of course the 800 lb gorilla is Fanuc, having sold 2.2 million control systems. While offering the ultimate in performance, Fanuc solutions come with minimum vendor independence and dismal ROI for those only needed mid-level performance. We believe a full service, professional grade supplier, offering complete control systems solutions, can be an effective competitor and is sorely needed by all levels of machine builders. We are not proposing open source hardware, but rather combining open source software with support and conventional industrial components to develop full spectrum solutions. This is not a matter of welcoming machine builders into the open source community; rather it is an issue of bringing the resources and value of open source to the market, offering attractive ROI to both customers and investor. *Details and How to Proceed:* We are looking to invest in a start-up business which meets the general goals as outlined above. We will provide the majority of capital and mentoring as needed. We will not participate in, nor attempt to control, the day to day activities of the business. If you want this to be your start-up business, submit a business plan to the email of Anonymous Investor at the address [backgroundpartner at gmail.com]. All submissions will remain confidential. There are many resources available for guidance on the development of a business plan, Google it. There is no specific timeline for this venture, but we will keep it open for at least 2 months. This is not a contest; it’s an investment and a partnership. A credible plan may be reviewed with suggestions for improvement. We have limited time for dialog and are unlikely to answer email from those with idle curiosity. *Anti-Spam and Scam Issues:* The legitimacy of this opportunity should speak for itself. This offer is only going out to the EMC email list and at no time will we ask for money, deposits, or personal financial information. Our anonymity will be removed for those whose negotiations appear credible and who sign non-disclosure agreement. Yours, Anonymous Investor -- What happens now with your Lotus Notes apps - do you make another costly upgrade, or settle for being marooned without product support? Time to move off Lotus Notes and onto the cloud with Force.com, apps are easier to build, use, and manage than apps on traditional platforms. Sign up for the Lotus Notes Migration Kit to learn more. http://p.sf.net/sfu/salesforce-d2d ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] EMC2 and 4th axis in milling: specifying speed and angular velocity?
Stephen, thanks, this is a wonderful way to implement this! i -- What happens now with your Lotus Notes apps - do you make another costly upgrade, or settle for being marooned without product support? Time to move off Lotus Notes and onto the cloud with Force.com, apps are easier to build, use, and manage than apps on traditional platforms. Sign up for the Lotus Notes Migration Kit to learn more. http://p.sf.net/sfu/salesforce-d2d ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] EMC2 and 4th axis in milling: specifying speed and angular velocity?
Igor Chudov wrote: > I am not too far from adding a 4th axis to my Bridgeport Interact > mill. The 4th axis will be a servo driven rotary table that sits > vertically on the milling table, so that the axis of the rotary ta ble > is parallel to X. > > I have a question, inspired by a recent discussion. > > Let's say I wanted to mill a helical spiral. > > Can I use EMC2 to instruct the milling table to move along X at a > given velocity, while at the same time, the rotary table is turning > with another given angular rotational speed. In other words, can I > specify two speeds, one for XYZ move and another for the angular > speed? > You can't specify two speeds, but you can decide how much to rotate the A axis (A is parallel to X) during the XYZ move. This is how the manual describes combined linear and rotary motion: "If any of XYZ are moving, F is in units per minute in the XYZ cartesian system, and all other axes (UVWABC) move so as to start and stop in coordinated fashion" So, if you want to make a helical groove that wraps around the workpiece 3 times, you need to perform a 1080 degree move (3 * 360) along with whatever the XYZ move is: G1 X 3 A 1080 F 1 The line above will make a single groove that wraps around the stock 3 times, with 1 inch spacing between, and it will take 3 minutes to complete (F1 for 3 inches = 3 minutes). So basically the rotational speed is adjusted so that the rotation takes the same amount of time as the linear motion. - Steve -- What happens now with your Lotus Notes apps - do you make another costly upgrade, or settle for being marooned without product support? Time to move off Lotus Notes and onto the cloud with Force.com, apps are easier to build, use, and manage than apps on traditional platforms. Sign up for the Lotus Notes Migration Kit to learn more. http://p.sf.net/sfu/salesforce-d2d ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] OT: Hall 10Bit 360° Programmable M agnetic Rotary Encoder
I have looked at these. The linearity is quite poor, see pg. 6 and 7 It looks like you might be up to 10 counts out at any position with an optimally placed magnet. Slotted encoders are usually out by a % of less than one count. The parameters will also change as the bearings wear over time. I think they are great for something like a butterfly valve or accelerator pedal where lots of discrete steps are required, but their relative accuracy is not important. Regards Roland On 8 December 2010 15:00, Andrea Montefusco wrote: > Hi all, > > Did anyone ever used this sensor ? > > http://docs-europe.electrocomponents.com/webdocs/0d59/0900766b80d59dc8.pdf > > on the paper it seems very interesting (1024 steps/turn up to 30K RPM). > > BTW: how about using them as encoders in a small gantry router ? > > *am* > > - > Andrea Montefusco iw0hdvhttp://www.montefusco.com > tel: +393356992791 fax: +390623318709 > - > > > -- > What happens now with your Lotus Notes apps - do you make another costly > upgrade, or settle for being marooned without product support? Time to move > off Lotus Notes and onto the cloud with Force.com, apps are easier to > build, > use, and manage than apps on traditional platforms. Sign up for the Lotus > Notes Migration Kit to learn more. http://p.sf.net/sfu/salesforce-d2d > ___ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > -- What happens now with your Lotus Notes apps - do you make another costly upgrade, or settle for being marooned without product support? Time to move off Lotus Notes and onto the cloud with Force.com, apps are easier to build, use, and manage than apps on traditional platforms. Sign up for the Lotus Notes Migration Kit to learn more. http://p.sf.net/sfu/salesforce-d2d ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
[Emc-users] EMC2 and 4th axis in milling: specifying speed and angular velocity?
I am not too far from adding a 4th axis to my Bridgeport Interact mill. The 4th axis will be a servo driven rotary table that sits vertically on the milling table, so that the axis of the rotary ta ble is parallel to X. I have a question, inspired by a recent discussion. Let's say I wanted to mill a helical spiral. Can I use EMC2 to instruct the milling table to move along X at a given velocity, while at the same time, the rotary table is turning with another given angular rotational speed. In other words, can I specify two speeds, one for XYZ move and another for the angular speed? I apologize in advance if I used wrong terminology. -- What happens now with your Lotus Notes apps - do you make another costly upgrade, or settle for being marooned without product support? Time to move off Lotus Notes and onto the cloud with Force.com, apps are easier to build, use, and manage than apps on traditional platforms. Sign up for the Lotus Notes Migration Kit to learn more. http://p.sf.net/sfu/salesforce-d2d ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
[Emc-users] THC and following error [was THC misbehavior]
Hello, folks! After my previous mail to the list I was encouraged by John Thornton to simplify thc.comp, and so I did. I removed several functions, including the idea that Z position is reported back without the offset added by thc. I would like thc to be as simple as possible - compare actual thc.volts and thc.volts-requested and then issue changes for Z position, if necessary. And that is it. I find it more convenient, if EMC receives back actual Z position, not the (actual - offset). And I find it more convenient, if that offset is not removed, once EMC knows the actual Z position. But the problem with this concept is that now I am stuck with a fundamental question - how to avoid following error on Z axis. The thing is that THC module "sits" between axis.3.motor-pos-cmd and stepgen.3.position-cmd, so the actual behavior after enabling THC is that axis.3.motor-pos-fb changes, while axis.3.motor-pos-cmd does not. And, if I understand correctly, then EMC checks difference between these two to calculate the amount of following error. So I have a question - is there a way to "tell" EMC, that joint.3 following error should be ignored, when and only when THC is enabled? But I suspect that I would get that following error as soon as THC is disabled. So can thc module be placed before axis.3.motor-pos-cmd? Or maybe something similar in this order: 1) taking axis.3.motor-pos-cmd value, saving it as "old value", e.g. axis.3.motor-pos-cmd-old 2) giving it to z-pos-in 3) calculating offset 4) giving new position data to z-pos-out 5) give z-pos-out value to axis.3.motor-pos-cmd Would something like this actually work? Thanks in advance! with best regards, Viesturs -- What happens now with your Lotus Notes apps - do you make another costly upgrade, or settle for being marooned without product support? Time to move off Lotus Notes and onto the cloud with Force.com, apps are easier to build, use, and manage than apps on traditional platforms. Sign up for the Lotus Notes Migration Kit to learn more. http://p.sf.net/sfu/salesforce-d2d ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
[Emc-users] OT: Hall 10Bit 360° Programmable M agnetic Rotary Encoder
Hi all, Did anyone ever used this sensor ? http://docs-europe.electrocomponents.com/webdocs/0d59/0900766b80d59dc8.pdf on the paper it seems very interesting (1024 steps/turn up to 30K RPM). BTW: how about using them as encoders in a small gantry router ? *am* - Andrea Montefusco iw0hdvhttp://www.montefusco.com tel: +393356992791 fax: +390623318709 - -- What happens now with your Lotus Notes apps - do you make another costly upgrade, or settle for being marooned without product support? Time to move off Lotus Notes and onto the cloud with Force.com, apps are easier to build, use, and manage than apps on traditional platforms. Sign up for the Lotus Notes Migration Kit to learn more. http://p.sf.net/sfu/salesforce-d2d ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Rotary Axis
Hi Len, >> I could see where you could configure the rotary axis as if it were a >> linear axis, but you'd have to reconfigure that axis and restart emc2 >> every time you changed stock to a different diameter. Another possibility, depending on the kind of work would be to configure the rotary as a linear axis of some fixed length and then scale that axis only of the drawing to suit. i.e. feed the machine a distorted drawing with A at the fixed length of the wrapped axis but X and Z normal size. One program which I have come across - ArtCam - uses a linear A axis but I can't remember how the scaling worked. I do know, however, that the company I saw it at produced decoration round a range of sizes from small ferrules for round knife handles up to large tea/coffee pots and the work was one-offs in the main. They didn't use EMC2 but I can't see how another program could be significantly different.. Ian -- What happens now with your Lotus Notes apps - do you make another costly upgrade, or settle for being marooned without product support? Time to move off Lotus Notes and onto the cloud with Force.com, apps are easier to build, use, and manage than apps on traditional platforms. Sign up for the Lotus Notes Migration Kit to learn more. http://p.sf.net/sfu/salesforce-d2d ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
