Auto Bed Leveling with an Inductive Proximity Sensor
Posted by quillford
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Auto Bed Leveling with an Inductive Proximity Sensor October 18, 2014 05:24PM |
Registered: 9 years ago Posts: 99 |
I have tried the following three inductive sensor on RAMPS 1.4, and none of them worked (1 2 3). I also tried the one on my Printrbot which worked. Two of the three sensors I tried are the same model number as the Printrbot probe. The problem I am having is that the probes will not change state even though the LED on the probe itself changes correctly. Is there something I need to do to the probes to make them work? Did I simply receive three defective probes?
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Re: Auto Bed Leveling with an Inductive Proximity Sensor October 18, 2014 07:26PM |
Admin Registered: 16 years ago Posts: 13,884 |
... several questions: - have you measured the output? - did it change with the LED or not? - which driving voltage (6-36V!) and how did you connect it to the 5V input?
Viktor
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Aufruf zum Projekt "Müll-freie Meere" - [reprap.org] -- Deutsche Facebook-Gruppe - [www.facebook.com]
Call for the project "garbage-free seas" - [reprap.org]
Viktor
--------
Aufruf zum Projekt "Müll-freie Meere" - [reprap.org] -- Deutsche Facebook-Gruppe - [www.facebook.com]
Call for the project "garbage-free seas" - [reprap.org]
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Re: Auto Bed Leveling with an Inductive Proximity Sensor October 18, 2014 07:28PM |
Registered: 9 years ago Posts: 99 |
I have not measured the output. It did not change with the LED. I connected it to the endstop positive and ground pins.Quote
VDX
... several questions: - have you measured the output? - did it change with the LED or not? - which driving voltage (6-36V!) and how did you connect it to the 5V input?
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Re: Auto Bed Leveling with an Inductive Proximity Sensor October 18, 2014 09:55PM |
Registered: 10 years ago Posts: 1,401 |
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Re: Auto Bed Leveling with an Inductive Proximity Sensor October 18, 2014 09:58PM |
Registered: 10 years ago Posts: 1,401 |
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Re: Auto Bed Leveling with an Inductive Proximity Sensor October 18, 2014 11:43PM |
Registered: 9 years ago Posts: 99 |
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Re: Auto Bed Leveling with an Inductive Proximity Sensor October 19, 2014 12:07PM |
Registered: 10 years ago Posts: 1,401 |
Using sensor 1 that is the correct type, connect brown to + blue to - and black to signal. Do M119 if shows triggered switch logic, do M119 and verify that is open, put a metal close to it and do M119 again should say triggered, if not, then you will have to used 12 volts and a voltage divider or LM7805 for signal to ramps.
Now this might be an stupid question: what kind of heated bed you have? Do you have enough metal there for the sensor to work properly?. I used capacitive sensors instead because they read any material and they read the top and not bottom of bed (glass), yes you need to have a table of offsets for different bed temperatures, but easy to do and to me they are more accurate.
Now this might be an stupid question: what kind of heated bed you have? Do you have enough metal there for the sensor to work properly?. I used capacitive sensors instead because they read any material and they read the top and not bottom of bed (glass), yes you need to have a table of offsets for different bed temperatures, but easy to do and to me they are more accurate.
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Re: Auto Bed Leveling with an Inductive Proximity Sensor October 19, 2014 12:10PM |
Registered: 10 years ago Posts: 1,401 |
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Re: Auto Bed Leveling with an Inductive Proximity Sensor October 19, 2014 12:54PM |
Registered: 9 years ago Posts: 99 |
I am not testing with my heated bed, so I will cross that bridge once I get the probe to switch logic. I am testing with an aluminum build plate that works with my Printrbot probe. I already connected them like that. I have not tried using 12V though. I do not understand why I would need 12V if the Printrbot probe works on Printrboard and RAMPS with 5V, but I will try 12V as soon as I get a voltage regulator.Quote
ggherbaz
Using sensor 1 that is the correct type, connect brown to + blue to - and black to signal. Do M119 if shows triggered switch logic, do M119 and verify that is open, put a metal close to it and do M119 again should say triggered, if not, then you will have to used 12 volts and a voltage divider or LM7805 for signal to ramps.
Now this might be an stupid question: what kind of heated bed you have? Do you have enough metal there for the sensor to work properly?. I used capacitive sensors instead because they read any material and they read the top and not bottom of bed (glass), yes you need to have a table of offsets for different bed temperatures, but easy to do and to me they are more accurate.
Edited 1 time(s). Last edit at 10/19/2014 12:55PM by quillford.
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Re: Auto Bed Leveling with an Inductive Proximity Sensor October 19, 2014 12:56PM |
Registered: 9 years ago Posts: 99 |
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Re: Auto Bed Leveling with an Inductive Proximity Sensor October 19, 2014 12:57PM |
Registered: 9 years ago Posts: 99 |
Will this work?Quote
ggherbaz
Using sensor 1 that is the correct type, connect brown to + blue to - and black to signal. Do M119 if shows triggered switch logic, do M119 and verify that is open, put a metal close to it and do M119 again should say triggered, if not, then you will have to used 12 volts and a voltage divider or LM7805 for signal to ramps.
Now this might be an stupid question: what kind of heated bed you have? Do you have enough metal there for the sensor to work properly?. I used capacitive sensors instead because they read any material and they read the top and not bottom of bed (glass), yes you need to have a table of offsets for different bed temperatures, but easy to do and to me they are more accurate.
Edited 1 time(s). Last edit at 10/19/2014 12:58PM by quillford.
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Re: Auto Bed Leveling with an Inductive Proximity Sensor October 19, 2014 02:59PM |
Registered: 10 years ago Posts: 1,401 |
Yes, that's an LM7805. In general any regulator to 5volts will work. Since amperage isn't an issue, you don't need to have a heatsink on it.
Your pull ups are set right, but logics might need adjustment depending on type of sensor.
Edited 2 time(s). Last edit at 10/19/2014 03:05PM by ggherbaz.
Your pull ups are set right, but logics might need adjustment depending on type of sensor.
Edited 2 time(s). Last edit at 10/19/2014 03:05PM by ggherbaz.
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Re: Auto Bed Leveling with an Inductive Proximity Sensor October 19, 2014 03:01PM |
Registered: 9 years ago Posts: 99 |
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Re: Auto Bed Leveling with an Inductive Proximity Sensor October 19, 2014 03:16PM |
Registered: 10 years ago Posts: 1,401 |
Like I said, i'm using capacitive ones, but it's just a matter of preferences and settings. I also used higher distance sensing 10mm instead of 4, this will be specially important if you are under powering the sensor at lower voltages sensing distance might be reduced rendering the sensor useless.
To check the sensor with just a power source and a bulb, if the sensor lights up the bulb, the sensor is in working condition, if no just send it back as defective.
To check the sensor with just a power source and a bulb, if the sensor lights up the bulb, the sensor is in working condition, if no just send it back as defective.
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Re: Auto Bed Leveling with an Inductive Proximity Sensor October 19, 2014 03:23PM |
Registered: 10 years ago Posts: 1,401 |
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Re: Auto Bed Leveling with an Inductive Proximity Sensor October 19, 2014 07:55PM |
Registered: 9 years ago Posts: 99 |
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Re: Auto Bed Leveling with an Inductive Proximity Sensor October 19, 2014 08:04PM |
Registered: 10 years ago Posts: 1,401 |
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Re: Auto Bed Leveling with an Inductive Proximity Sensor October 19, 2014 08:53PM |
Registered: 9 years ago Posts: 99 |
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Re: Auto Bed Leveling with an Inductive Proximity Sensor February 02, 2015 05:23AM |
Registered: 11 years ago Posts: 1 |
I'm kind of late to this discussion...
I like a longer working distance for a capacitive sensor, but I was living under the impression that sensor repeatability is of the order of a few percent of the total scale. The video you suggested mentions a 2% repeatability, and if I use that then you get the measurement error within 0.2mm. I'd like the measurement error to be <0.1mm, but would like a longer working distance.
Can you comment on the repeatability of the capacitive sensor you are using? Maybe providing a part number?
Thanks.
I like a longer working distance for a capacitive sensor, but I was living under the impression that sensor repeatability is of the order of a few percent of the total scale. The video you suggested mentions a 2% repeatability, and if I use that then you get the measurement error within 0.2mm. I'd like the measurement error to be <0.1mm, but would like a longer working distance.
Can you comment on the repeatability of the capacitive sensor you are using? Maybe providing a part number?
Thanks.
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Re: Auto Bed Leveling with an Inductive Proximity Sensor February 03, 2015 03:51AM |
Registered: 10 years ago Posts: 14,672 |
I use a heated bed PCB with an aluminium heat spreader on top and then a glass print bed. I had capacitive sensing working, but the capacitance is small and sensitive to both the thickness of the glass and to whatever coating you use on it to improve adhesion. As I swap glass print beds between prints, I wanted a solution that measures the distance to the top surface of the glass rather than the bottom surface. Inductive sensing would have had the same problem. I settled on a system using two infrared LEDs and one phototransistor. There are now about 100 Ormerod printers using one of my sensors, and most report good results. See [miscsolutions.wordpress.com] for more info and a link to the schematic and firmware.
Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod
Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].
Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod
Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].
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Re: Auto Bed Leveling with an Inductive Proximity Sensor February 10, 2015 12:51AM |
Registered: 9 years ago Posts: 2 |
dc42,
I am working on my reprappro auto-leveling. It works great with an inductive sensor with an exception that the sensor has bad (~1mm) temperature drift. I tried Omron EESPY302 IR sensor and the repeatability was not good at all. It's not easy to find an inexpensive sensor with acceptable repeatability and temperature drift. I am waiting for a Fotek PS-15N sensor from Taiwan now.
Your solution sounds very interesting. Do you deal with temperature drift in firmware or hardware? I see you also experimenting with ultrasound sensor. I could not find a link to schematics on your website. Do you mind posting a link?
I am working on my reprappro auto-leveling. It works great with an inductive sensor with an exception that the sensor has bad (~1mm) temperature drift. I tried Omron EESPY302 IR sensor and the repeatability was not good at all. It's not easy to find an inexpensive sensor with acceptable repeatability and temperature drift. I am waiting for a Fotek PS-15N sensor from Taiwan now.
Your solution sounds very interesting. Do you deal with temperature drift in firmware or hardware? I see you also experimenting with ultrasound sensor. I could not find a link to schematics on your website. Do you mind posting a link?
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Re: Auto Bed Leveling with an Inductive Proximity Sensor February 10, 2015 05:12AM |
Registered: 10 years ago Posts: 14,672 |
Quote
seavan
Your solution sounds very interesting. Do you deal with temperature drift in firmware or hardware? I see you also experimenting with ultrasound sensor. I could not find a link to schematics on your website. Do you mind posting a link?
You can find the schematics at [github.com]. I deal with temperature compensation for the ultrasonic sensor in the 3D printer firmware, see the S and C parameters in the G31 command description at [reprap.org]. However, I don't recommend the ultrasonic sensing, because if you use it when the bed is hot, the reading is affected too much by draughts. The sensitivity to temperature is a fundamental limitation of ultrasonic sensing, caused by the variation the speed of sound in air with temperature.
Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod
Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].
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Re: Auto Bed Leveling with an Inductive Proximity Sensor February 10, 2015 06:57PM |
Registered: 9 years ago Posts: 2 |
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Re: Auto Bed Leveling with an Inductive Proximity Sensor May 06, 2015 05:26AM |
Registered: 9 years ago Posts: 112 |
HI, I new in 3d printing and currently i'm having a new prusa i3 with Proximity Sensor, the issue is this sensor home correct but make my nozzle out of space, can anyone teach me how to move the nozzle to the home correctly, instead of sensor at home and nozzle out of heatbed, appreciate any kind person can tell me!
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Re: Auto Bed Leveling with an Inductive Proximity Sensor May 06, 2015 03:12PM |
Registered: 10 years ago Posts: 1,401 |
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Re: Auto Bed Leveling with an Inductive Proximity Sensor July 12, 2016 06:10PM |
Registered: 7 years ago Posts: 8 |
I am trying to set this up. I have a Prusa I3 printer and changed to a OSOYOO MKS Base V1.4 3D Printer Controller remix Board.
I got an Inductive Sensor (LJ18A3-8-Z/BX 8mm Approach Sensor Inductive Proximity NPN NO Switch DC 6-36V)
I connected it to the 12V supply and put a resistive divider on the output to neg supply.
I measure the output after dividing it and it (not connected to board) reads 4.56 Vdc and
I put it on my aluminum bed, the light lites and the output drops to 0Vdc.
So I know the sensor is working. I connect it to the Z- input and the output starts at the 4.56Vdc and
when triggered it only drops down to 3.3Vdc which is too high to trigger the circuit.
I have removed all pullups and enabled all pullups...It doesn't seem to make a difference.
I do not know what to do next.
I got an Inductive Sensor (LJ18A3-8-Z/BX 8mm Approach Sensor Inductive Proximity NPN NO Switch DC 6-36V)
I connected it to the 12V supply and put a resistive divider on the output to neg supply.
I measure the output after dividing it and it (not connected to board) reads 4.56 Vdc and
I put it on my aluminum bed, the light lites and the output drops to 0Vdc.
So I know the sensor is working. I connect it to the Z- input and the output starts at the 4.56Vdc and
when triggered it only drops down to 3.3Vdc which is too high to trigger the circuit.
I have removed all pullups and enabled all pullups...It doesn't seem to make a difference.
I do not know what to do next.
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Re: Auto Bed Leveling with an Inductive Proximity Sensor July 12, 2016 07:56PM |
Registered: 10 years ago Posts: 1,401 |
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Re: Auto Bed Leveling with an Inductive Proximity Sensor July 18, 2016 01:01PM |
Registered: 9 years ago Posts: 29 |
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Re: Auto Bed Leveling with an Inductive Proximity Sensor July 18, 2016 01:21PM |
Registered: 12 years ago Posts: 548 |
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Re: Auto Bed Leveling with an Inductive Proximity Sensor July 18, 2016 01:49PM |
Registered: 9 years ago Posts: 29 |
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