Suppose there is a food production plant where chocolate is made. The chocolate trays come into the production line and have to pass through a metal detector to check the metal containment. If a metal object is found in the chocolate tray, it is sent to the rejection bin. If there is no metal object, then the chocolates are sent for packaging.


That is why the plant head has given instruction to the machine operator, it has to check whether the metal detector is working or not by passing the metal plate in front of the metal detector thrice a day. If the test is successful all three times, he has to maintain record in the register that he has successfully conducted all the three tests along with the time and date.

But problem is that the plant head found in the camera that the operator sometimes checks the metal detector and never checks but he maintains the register daily. So the plant head reported the matter to his senior in head office.

Management passed an order stating that they wanted a system that checks how many times in a day the operator is testing the metal detector when the operator takes the test it need to send alert notification to the mobile of plant head and senior at head office. Also store alerts message with time and date in database.

if i need to select device for such system i will choose raspberry pi or ESP32 board. As a designer, What would you recommend?

 

I think it would be easier to automate the checking rather than trying to confirm that the operator performed and recorded the test. The sequence I would choose would to log the state of the output on the metal detector and log it with a time stamp. Command an actuator to move the plate under the metal detector. Log the state of the metal detector again together with a time stamp. Command the actuator to retract the plate from under the metal detector. And finally log the state of the metal detector output together with a time stamp. The three states of the detector output together with the time stamps could then be transmitted to the database. If the three tests did not follow the pattern clear, metal detected and clear a warning could be added to the message sent to the data base and a relay operated to prevent production from continuing. These events could be controlled using a cheap PIC or Atmel chip (Which would cost about £1.00) Adding an RTC chip would simplify the software as the software would no longer have to keep track of the time. If the message had to be sent via wi-Fi then an ESP32 or raspberry Pi would be a better choice. The choice depends a lot on the details of the situation. On the computer that did the logging of the data a check could be made that if more than a certain amount of time had elapsed since the last message had been received it would take some action such as warning management.

Les.

 

I think it would be easier to automate the checking rather than trying to confirm that the operator performed and recorded the test. The sequence I would choose would to log the state of the output on the metal detector and log it with a time stamp. Command an actuator to move the plate under the metal detector. Log the state of the metal detector again together with a time stamp. Command the actuator to retract the plate from under the metal detector. And finally log the state of the metal detector output together with a time stamp. The three states of the detector output together with the time stamps could then be transmitted to the database. If the three tests did not follow the pattern clear, metal detected and clear a warning could be added to the message sent to the data base and a relay operated to prevent production from continuing. These events could be controlled using a cheap PIC or Atmel chip (Which would cost about £1.00) Adding an RTC chip would simplify the software as the software would no longer have to keep track of the time. If the message had to be sent via wi-Fi then an ESP32 or raspberry Pi would be a better choice. The choice depends a lot on the details of the situation. On the computer that did the logging of the data a check could be made that if more than a certain amount of time had elapsed since the last message had been received it would take some action such as warning management.

Les.

@LesJones Thank you

I'm glad you mentioned raspberry and ESP32 in choice. But I don't understand how PIC or Atmel with RTC would be suitable for this project. We can keep record of date and time with RTC but we cannot send it to head office. recorded data will be sent to cloud machine.

The process is such that when the operator puts the metal plate in front of the metal detector, the detector generates a sound, which shows that the metal detector is active. When the metal detector detects metal it sends a signal to the RPi, so when the pi receives an active signal it records an alert message with time and date and send the record to cloud machine.

I think an app would be needed to receive alert messages in mobile. So the data that will be received in the cloud has to be inserted in the mobile app.