Here is the famous Edison bistro table !
During the Intel IoT Roadshow session in Paris, I made a Cloud connected table for restaurants with my team. We had many objectives for this hackathon with this table:
- Allow restaurant managers to monitor their daily table usage
- Allow customers to find available tables inside or outside of restaurants
- Improve customer reception
- Improve customer comfort
- Improve payment process
Step 1: The Plan
The plan was to create a table equipped with the Edison board and some sensors:
- Presence sensors on the sides of the table to detect customers
- Some LEDs to simulate the communication with the Cloud
- A light sensor on the top of the table to detect if the user is looking at the menu
- A tiny LCD screen to send some messages to the customer
- A temperature sensor + rotary angle to manage temperature (and to use a maximum of IOs for the hackathon)
- A GPS/Accelerometer + Buzzer to protect the table from thieves (and to use a maximum of IOs for the hackathon)
The plan was to integrate the complete stuff inside the table top board.
Step 2: Prepare the Electronic
The first technical step was to test all electronic components we wanted to use... We made little circuits like:
Edison + Temperature sensor + Rotary angle
We just tried to get the temperature, get values from the rotary angle, transform that into degrees values...
Edison + Temperature sensor + Rotary angle + LCD
We added the LCD to get a feedback of the values and let the user set a temperature target.
Edison + HC-SR04
We tried to make the sonar HC-SR04 work with the Edison board to detect the customer near the table. Unfortunately we failed to make it work so we used the IR Interrupter. The problem of this other component is that it can only detect object distant of 1~3cm. That will be enough for the demo but not for the final product.
Edison + Light sensor
The groove light sensor was working well but its shape was not adapted to our usage. The sensor and the wires were on the same side of the circuit... So we made our own from a simple Light Dependent Resistor (LDR) to be able to have a good looking table.
Edison + GPS
This was working well ! ... but outside :-(
Edison + Accelerometer + Buzzer
Edison can get values quite easily from this sensor. We used it to replace the GPS. The problem was to get the good threshold to activate the buzzer to prevent the stealing of the table.
Step 3: Prepare the Table
We used a big cardboard box that we cut at roughly 8cm to simulate our table board. The top of the table board has been made of a cardboard sheet glue with a sheet of polystyrene to make it a bit stronger.
Then we wired the box, the IR sensors on the sides, the LCD & rotary angle sensor between the cardboard and the polystyrene sheet on the top. The same for the LEDs and the light sensor.
We wired all theses sensors to the Edison inside the box. We added a nice black tablecloth with some holes to make it well finished.
Finally we had to assemble all pieces of code to make a full IoT product.