bottle inspection machine  - Page 1
Forum section: electronics / projects

author: BlogRahul
author_rank: Regular Contributor
timestamp: November 30, 2021, 12:30:37 pm
content: I found a video on Youtube showing how to inspect defectives bottles on the conveyorLink for videoinspection cabin tell which bottle is defective and rejection station send the defective bottle into rejection bin.I wonder how defective bottle get rejected on belt I don't understand logic because inspection cabin and rejection system are far away.How does rejection system know that which bottle need reject at rejection stationDoes anyone have any idea

author: wraper
author_rank: Unknown
timestamp: November 30, 2021, 12:36:03 pm
content: QuoteLine moves at known speed, so the time when defective bottle needs to be removed is known. Also there may be an optical sensor which detects the bottle and can also be used for counting them.

author: BlogRahul
author_rank: Regular Contributor
timestamp: November 30, 2021, 12:45:00 pm
content: Thanks! This means that belt speed should be always constant. We will not get the correct result if the belt speed is more or less.Do you have any idea if the belt speed is adjustable then How the rejection system will work ?

author: wraper
author_rank: Unknown
timestamp: November 30, 2021, 01:02:08 pm
content: I don't know about this exact system but it's quite easy to regulate the belt speed in closed loop or measure its speed.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: November 30, 2021, 01:43:26 pm
content: An inspection camera can also potential measure the speed

author: Ian.M
author_rank: Super Contributor
timestamp: November 30, 2021, 02:43:03 pm
content: Its trivial for the inspection station to queue rejections and delay actuating the rejection ram till the belt has moved the required distance to the rejection station. If there's a transition to another belt in-between, a bottle counter just before the rejection ram may be required.

author: BlogRahul
author_rank: Regular Contributor
timestamp: December 01, 2021, 12:14:43 pm
content: Quote from: Ian.M on November 30, 2021, 02:43:03 pmI really don't understand how the rejection will happen when the belt speed is adjustable? I found that the encoder used in this kind of machine

author: tooki
author_rank: Super Contributor
timestamp: December 01, 2021, 07:02:22 pm
content: Speed x time will always give you distance. Or you could literally just measure distance: suppose you put an encoder on your belt that gives 1 pulse per cm. If you know the rejection station is, say, 250cm from the vision station, then you count 250 pulses and then trigger rejection. The speed of the belt doesn’t matter.

author: Carel
author_rank: Regular Contributor
timestamp: December 01, 2021, 10:20:56 pm
content: I once worked at a factory that produced machines for the yeast (and penicillin) industry. Yeast was extruded, cut to pieces, packaged and sealed. If it was sealed well, the package was hard.So a short distance further down the line a pneumatic device attacked the package, if it went too far due to softness, a gate opened behind the package and off it went with the same device. 1980. The best solutions are simple. And it was fun to see.

author: bdunham7
author_rank: Super Contributor
timestamp: December 01, 2021, 10:28:15 pm
content: Quote from: tooki on December 01, 2021, 07:02:22 pmOn a long-looped conveyer, you could also have a reference ID of some sort, visual or otherwise, for each bottle position. So if the inspection unit flags a defect, it also flags the ID of the spot on the conveyor and then the kicker can get it when that ID gets to it.

author: quemajico
author_rank: Newbie
timestamp: December 02, 2021, 07:53:38 am
content: Bottle conveyors allways have an encoder, to seek preciselly the position on the conveyor, so the controller can track the exact position at the inspection point and follow the bottle to the rejection point.Problems arrise when the line adjust speed and can occur some slip or displacement to the bottle. May times thre are also photoelectric switches to try to match the supposed position whith the real one.Usually also exist displacement registers to track all the bottles from the inspection point or points to the pusher, for each bottle, at the point where enters the machine, a register tracks the position and the status of the inspection (maybe more than one), and with this status, the machine selects also the rejection point, as sometimes, there are different pushers to save or destroy the bottle.Best regards

author: BlogRahul
author_rank: Regular Contributor
timestamp: December 02, 2021, 09:58:25 am
content: Quote from: tooki on December 01, 2021, 07:02:22 pmThe hard part of this system is to understand how an empty bottles are rejected at the right place on the belt.I assume we count 2000 pulse from inspection to rejection I don't understand if all bottles are empty from inspection to rejection point, then how the bottles will be removed

author: Steffalompen
author_rank: Contributor
timestamp: December 02, 2021, 01:25:54 pm
content: Quote from: BlogRahul on December 02, 2021, 09:58:25 amEither quickly with one pusher, with multiple pushers, or stop the line entirely because something is obviously very wrong.A line of bottles resemble a shift register, and that is a useful clue to a possible path to minimize uC programming.

author: BlogRahul
author_rank: Regular Contributor
timestamp: December 02, 2021, 02:29:38 pm
content: Quote from: Steffalompen on December 02, 2021, 01:25:54 pmCan you please explain how the rejection will happen based on location?There is no such microcontroller in my knowledge that has inbuilt shift register features. Will shift register Ic have to interface with micro ?

author: Steffalompen
author_rank: Contributor
timestamp: December 02, 2021, 05:19:55 pm
content: There are so many possibilities and I don't know your production line. I think unless I need a uC for something else to do with this I might forego with it entirely and use the bottles as clock pulse and ADC their status into a sequence of rejection with s.regs.

author: BlogRahul
author_rank: Regular Contributor
timestamp: December 03, 2021, 11:29:42 am
content: I have searched more about this topic on the internet but I don't get much information. I don't know how the location of each bottle will be tracked. I don't understand the logic of shift register with microcontroller.

author: Steffalompen
author_rank: Contributor
timestamp: December 03, 2021, 11:50:44 am
content: By chance I went and googled "programming shift register" to see if I could find one done only in code.The first result was programming a PLC for a bottle filling lineSay there's 8 bottle positions between your scanner and your mechanism. When the scanner reads an anomaly it puts it into the register as a one, 00000001. With incrementing bottles it shifts it left 00001000 etc, perhaps another anomaly occurs 00010001, it reaches the end where the mechanism reads the one and outs the bottle10001000.This gets rid of timing an accurate delay, and of juggling potentially many anomalies each with it's own increment counter in code.

author: BlogRahul
author_rank: Regular Contributor
timestamp: December 03, 2021, 12:37:22 pm
content: Quote from: Steffalompen on December 03, 2021, 11:50:44 amThanks for the reply. My problem is that I don't understand the program for PLC. I only work with microcontrollerMy question is Do I need to connect shift register Ic with a microcontroller ? I don't know any micro that has inbuilt shift register features

author: Steffalompen
author_rank: Contributor
timestamp: December 03, 2021, 12:56:54 pm
content: I realise you are using uC and not PLC, but the principle is the same.By now I hope you have looked beyond code and that you are onboard with the very simple analogy between bottles on a conveyor and digital shift registers. They're basically the same.Yes. (and they can be connected in series)Or it can be done in code.

author: Psi
author_rank: Super Contributor
timestamp: December 03, 2021, 01:18:04 pm
content: The conveyer is likely driven by a stepper motor and the control system is advancing the belt position by a number of steps per second.Hence the speed of the production line can be adjusted to whatever is needed in real-time but the control system can always maintain tracking on how far bottles are moving through and know exactly when they will pass any future point along the line.The example above is pretty trivial. It's more impressive seeing a stream of widgets falling off an edge while a computer scans, identifies and then aims and fires a blast of compressed air at exactly the right time to alter that parts landing position into a different bin.(There is a video of this but I cant seem to find it)

author: BlogRahul
author_rank: Regular Contributor
timestamp: December 03, 2021, 01:55:56 pm
content: Quote from: Steffalompen on December 03, 2021, 12:56:54 pmWhich Serial-in, serial-out shift registers IC will be suitable with 8 bit uC for the projectjust google searched and got 74LVC595A is an 8-bit serial-in/serial

author: tooki
author_rank: Super Contributor
timestamp: December 03, 2021, 09:38:28 pm
content: You don’t need a shift register. You need to think about what a shift register does, and why doing something similar in code would solve your problem.

author: rpiloverbd
author_rank: Regular Contributor
timestamp: December 04, 2021, 05:18:32 am
content: What I can understand from the animation, either there are multiple sensors in the rejection block, or they are using image processing.I could see many types of defected bottles here. Such as-EmptyHalf emptyWrong corkscratched corkA filled bottle can be differentiated from the empty one by optical sensor, the same sensor that we use in line followers. A pressure sensor/weight can do the task too. Obviously, a filled bottle weights more than an empty or half empty one. Black cork can be detected by optical sensors too.If they are using a raspberry pi with a camera, they can detect all types or faulted bottles by image processing. The best way to do this is to apply machine learning.

author: BlogRahul
author_rank: Regular Contributor
timestamp: December 04, 2021, 11:35:33 am
content: Quote from: tooki on December 03, 2021, 09:38:28 pmI assume 8 bottles fit between the scanner and rejection point. there is a variable that stores 8-bit data ( 00000000 ). scanner scan the bottle and put 1 in a shift register if bottle defects otherwise position would be 0 and position will sift for next bottleThis 00010010 sequence show that bootles at 2nd and 5th position defectThe rejection point only checks the last bit if it's 1 or 0. if the bit is 1 then bottle will removed from lineBut Its not undersood how the bit positon will shift for ecach botle between scanner and rejection

author: Renate
author_rank: Super Contributor
timestamp: December 04, 2021, 01:19:15 pm
content: As stated above, there could be multiple sensors at multiple locations. Maybe one looks at caps at one location and another checks for correct filling level at another location.This doesn't alter the algorithm.Code:Sensor A|| Sensor B| || | Sensor C| | || | | Reject| | | || | | |0 0 0 0 0 0 0 everything ok0 0 1 0 0 0 0 B detects0 0 0 1 0 0 0 shift1 0 0 1 0 0 0 A detects0 1 0 0 1 0 0 shift0 0 1 0 0 1 0 shift0 0 0 1 0 0 1 shift & reject for B failure0 0 0 0 1 0 0 shift0 0 0 0 0 1 0 shift0 0 0 0 0 0 1 shift & reject for A failure0 0 0 0 0 0 0 shift & everything ok

author: Steffalompen
author_rank: Contributor
timestamp: December 04, 2021, 02:21:33 pm
content: I understood this notsomuch as "how exactly did they do everything in this video" and more as "I wish to check and reject unfilled bottles somewhat like this".We really need to know more about the project.But the clues this far, like the level of knowledge, hints to keeping it simple.That's why I go with a more primitive industry-automation type solution instead of steppers, loads of sensors and tons of code.The ideal solution to keep it simple would be to combine the detection and rejection into one position.

author: BlogRahul
author_rank: Regular Contributor
timestamp: December 05, 2021, 12:31:28 pm
content: Quote from: Steffalompen on December 04, 2021, 02:21:33 pmAgree, A lot of things are unclear in the video but with the help of all of you guys, I can now understand how any object reject on a conveyor belt. I am doing more research on it I'll come back with a specific question

author: tooki
author_rank: Super Contributor
timestamp: December 05, 2021, 01:23:43 pm
content: Quote from: BlogRahul on December 04, 2021, 11:35:33 amEither the clock that drives the belt, or the encoder used to monitor it.