Homing and Precision Homing with ClearPath Integrated Servos

[@SuperYellowsubmarin]

I already use the hard stop homing on my lathe and it works quite well. But this will definitely be a plus, I'll upgrade today. Thank you for supporting your products in the long run. The autonomous homing procedure is useful for DIY CNC because if makes for a much more accurate homing that inductive or mechanical sensors, and does not waste the feedback line (have to use it as fault feedback) or any CNC controller input.

[@signaturemotion7852]

Awesome, love new content! Really hoping you are making more videos because it goes a long way to showing what is possible!

[@getinthespace7715]

Very cool. I'm designing a simple piece of equipment that requires speed control, a start button, a home button and an e-stop. I was considering using the ClearCore and incorporating limit switches... but I don't think I need that anymore. 1 pwm speed control and 2 buttons I should be able to setup with just the I-O on the integrated motor controller if I use torque limits for hard stop homing. This feature is great. Saves time and reduces hardware and failure points.

[@TeknicInc]

Hi getinthespace7715, Yes, exactly, a big benefit of the ClearPath’s Hard-Stop Homing feature is reduced hardware and failure points. The description of your application has me curious, though. Most ClearPath applications that use PWM to control speed are for axes that can rotate indefinitely, and therefore don’t need to homed. It’s possible that your application is unique, but it might be helpful to give us a call and speak with an engineer. We’d be happy to make sure you are getting the most appropriate motor for your needs, and make sure that everything will work the way you want it to the first time around. You can speak with a Teknic Applications Engineer by calling 585-784-7454, or leaving a message at teknic.com/contact/. Best regards, Ian R., Teknic Servo Systems Engineer

[@TeknicInc]

Hi getinthespace7715, Yes, exactly, a big benefit of the ClearPath’s Hard-Stop Homing feature is reduced hardware and failure points. The description of your application has me curious, though. Most ClearPath applications that use PWM to control speed are for axes that can rotate indefinitely, and therefore don’t need to homed. It’s possible that your application is unique, but it might be helpful to give us a call and speak with an engineer. We’d be happy to make sure you are getting the most appropriate motor for your needs, and make sure that everything will work the way you want it to the first time around. You can speak with a Teknic Applications Engineer by calling 585-784-7454, or leaving a message at teknic.com/contact/. Best regards, Ian R., Teknic Servo Systems Engineer

[@Evan-inc.]

But *HOW* does it work?

[@CrazyMineCuber]

By reading a document from clearpath, it appears that precision homing is done through the software remembering the partial rotation of the motor during the initial homing calibration. Then, if the end stop gets worn down by a mm, the software can still use the information from the endstop to restore the correct full number of motor rotations, but the partial motor rotation is reset from the initial calibration. This means that the motor can correct for worn down endstops up to +- half a motor turrn.

[@SuperYellowsubmarin]

On the first homing it will memorize the encoder count. Then the homing procedure will only be used to identify on which rotation to home, and the encoder count on that rotation will do the rest.

[@TeknicInc]

Hi @Evan-inc. As @CrazyMineCuber and @SuperYellowsubmarin said, precision homing can automatically account for variations in the physical home position (either a hard stop or sensor) because the motor "calibrates" the home location the first time it is homed. Then, the motor references that calibrated position every time it needs to home again. As you can see in the video, even after adding the shim or removing the bumper, we home the motor until it detects the hard stop. Upon reaching the hard stop, the motor compares the measured home location to the calibrated home location and automatically accounts for any difference between the two (up to +/- 0.5 motor revs). Precision homing can also be used with a sensor to compensate for variations in sensor position and homing speed. For more information about homing a ClearPath motor, I suggest checking out the ClearPath User Manual found on our website: teknic.com/downloads/. If you have any additional questions about precision homing or anything else, please feel free to contact us directly at teknic.com/contact or give us a call at 585-784-7454. Thanks, Jon K. - Teknic Servo Systems Engineer

[@jamesbarratt593]

Im about to buy clear path SDSK-3421S-RLN for X and Y and then SDSK-3432S-RLN for Z axis. Just wondering for my mill should I get the HP models which cost a little more but then supposed to be very very good.

[@TeknicInc]

Hi James I'm an applications engineer with Teknic and would like to help answer your question. The primary difference between the SDSK and the SDHP is that the SDHP has more shaft power. Because shaft power is the product of speed and torque you can get more power by either spinning faster, producing more torque, or both. The other notable difference is that the SDHP models come standard with the "Enhanced" ("E" versus "R" in the part number) encoder option with a command resolution of 6,400 quad counts/rev versus 800 quad counts per rev on the SDSK. The Enhanced option also includes the full complement of the Regressive Auto Spline settings for double jerk limiting your profile for smoother motion. For most CNC mill retrofit kits, the power and capability of the SDSK closed-loop servo series is more than sufficient. As an example, many of these CNC retrofit systems use ballscrews with a 5 tpi pitch (0.2 inch lead) so, with the CPM-SDSK-3421S-RLN motor at 75 Vdc, you can theoretically achieve 200 inches/min (1,000 rev/min x 0.2 inches/rev = 200 inches/min). There are naturally a lot of factors that go into picking the optimal motors for your CNC upgrade, but I would start with determining what top speeds (during both rapids and cutting) are important for your application. By understanding the top speed objectives along with your mechanics, you can then narrow down the motor selection. If you have any further questions, please feel free to contact Teknic at 585-784-7454 or submit a contact request at teknic.com/contact/. Thanks, Abe A. - Teknic Applications Engineer

[@jamesbarratt593]

⁠​⁠@@TeknicIncwould you know can I use Centroid 6 axes with your motors sdsk 3421s-rln and 3432 sdsk motor?

[@TeknicInc]

Hello ​James, We don’t personally have direct experience with the Centroid CNC controllers but we do know that many mutual customers use them and seem to be quite pleased with the performance and capabilities. The controllers well-suited for use with ClearPath SDSK and SDHP motors are the Centroid Acorn and AcornSix. There’s also a convenient break-out board for routing control signals from the controller to the ClearPath motors (you can use our standard controller cables without modification). This break-out board is produced and sold by CNC4PC and is called the “C89-ACCP”. www.cnc4pc.com/c86accp-clearpath-connector-board-for-the-acorn-controller.html If you decide to use the Centroid Acorn controller, I’d also recommend the KZbin channel, MartysCNCGarage. It’s an excellent educational resource for CNC hobbyists using ClearPath motors with the Acorn controller. kzbin.info/door/TNt9IIjsk5HNwnjzer6GVQvideos www.cnc4pc.com/c86accp-clearpath-connector-board-for-the-acorn-controller.html) If you have any further questions, please feel free to contact Teknic at 585-784-7454 or submit a contact request at teknic.com/contact/. Thanks, Abe A. - Teknic Applications Engineer

[@jamesbarratt593]

@@TeknicInc I was trying to read the Acorn Six Datasheet and picked up on something I dont know whether its important or no. Basically it mentions AC motors and I'd though for some reason your motors were dc. I guess the DC part doesn't matter as they will have their own IPC5 power supply. The acorn six with software looks very impressive. So buy that and the breakout board from cncpc then your motors and ipc5 plus cables. Thats a good setup then?

[@maxcnc]

If this motor has an absolute encoder to memorize the position, why does it need to pump to a hard stop? you can simply home it once forever.

[@TeknicInc]

Hi PLC24_max10: Thanks for commenting and taking the time to ask a question. Teknic motors have incremental (not absolute) encoders onboard. We’ve found that incremental encoders tend to be more reliable and less expensive than absolute encoders, which is why we use them in all of our motors. To provide some of the benefits of absolute encoders without the drawbacks, Teknic developed the Precision Homing feature demonstrated in this video. Precision Homing works because the motor “calibrates” and stores (in non-volatile memory) the physical home position the first time it is homed on a set of mechanics. The motor can then reference this stored home position on each subsequent homing cycle. While we still need to home the axis after the machine is power cycled, Precision Homing combined with ClearPath’s Position Recovery feature (demonstrated here: kzbin.info/www/bejne/o3KvmmaVhtasfs0si=B-RDD600dfYfUctP&t=458), can provide much of the benefits of an absolute encoder as long as you maintain logic power at the motor(s). Please feel free to give us a call (585-784-7454) or leave us a message at teknic.com/contact/ if you have any additional questions. Best regards, Jon K. - Teknic Servo Systems Engineer

[@elsunshine9976]

Price?

[@TeknicInc]

Hi el SunShine, Precision Homing is a feature included in all ClearPath SD and MC series motors at no additional cost. If you're looking for product pricing information, this is available on the Teknic website (teknic.com/). If you have any further questions, please feel free to submit a contact request on Teknic’s website at teknic.com/contact/ or give us a call at 585-784-7454. Aimee F. - Teknic Applications Engineer

[@elsunshine9976]

​@@TeknicInchow fast would you be able to ship to Mexico

[@TeknicInc]

Hi @@elsunshine9976, The answer to your question depends on the part number(s) and quantities being ordered. All product-specific information regarding shipping and lead times can be found directly on the Teknic website. Here is a link to Teknic's FAQ's page which includes more information about international shipping: teknic.com/faq/?faq=9#faq_international Aimee F. - Teknic Engineer

[@G5Ckxew]

There's no place like home

someone had to say it.... lol

[@jamesbarratt593]

Before you waste time in these motors know one thing. I spent days familiarising myself on them only to find at checkout I cant buy any. Reason being is the firm only take credit card. After two emails I am finally told to go to motion industries and in doing so I loose money back guarantee. I pay more and they take longer to be sent to me. One of these motor is over $500 and the established firm only take credit cards.

[@TeknicInc]

Hi James, We appreciate your feedback to improve our e-commerce resources for customers and I will pass your suggestions on to our management and marketing teams. We work hard to make the information about our products, ordering, and services as clear as possible to prevent prospective customers from wasting their time if there is a reason they cannot move forward with our products. Our webstore currently accepts all major credit cards such as Visa, Mastercard, Discover, and AMEX, but as you unfortunately found out, it does not accept debit cards. A notable reason for this is that debit cards have a higher level of fraud risk for the vendor (Teknic). We continuously evaluate payment options (e.g., PayPal, Venmo, Zelle, and even crypto), but each option has different transaction fees, costs, and risks with incorporating them into the third-party checkout modules we license. Best of luck with your application and I apologize again for any confusion about our ordering process. Best, Bridgette O. - Teknic Servo Systems Engineer

[@jamesbarratt593]

@@TeknicInci use stripe on my ecommerce website to handle all card types. Credit and debit. To mention charges for uses debit card is one reason you dont accept them when your motors alone can be over $500 each makes me laugh. I offered to wire funds direct to your account. Rather than accept knowing the trouble I have been put through and that the money was over $1800 dollars, neither was my idea accepted or even spoken about. My time was wasted.