Mechanical Design¶
The Spice mixer¶
For our group project, we decided to design a spice mixer! Arabic food is considered spicy, if you want to learn how to prepare any dish you have to master mixing the right amount of spices and the right types! this machine does all the mixing automataically! we programed it to do one dish recipe as a start but ideally we hope that one day we can have a list of recipes that our machine can follow and prepare.
How we planned and executed the project?¶
At first we wrote down the main components of our machine:
- Linear system where spices bowl slides under the spice dispensers.
- Dispense system.
- Electronics.
- integration system (frame).
After dividing the components it was easy for us to divide the tasks so we can work in parallel to each other.
1- Linear movement requires design and 3D printing of several parts. this task was given to Lina Hudaib.
2- Dispensers and dispense systems require design and 3D printing. this task was given to Mohammad shuqwara and Ahmad Jaara.
3- Electronics design and integration system design was given to me (Rasha Khalifeh)
4- production of the integration system was given to Ismael Qashou.
5- Soldering and asembling of electronics was given to Lina hudaib.
6- Video and presentation was done by me (Rasha Khalifeh).
Integration system (frame)¶
As a bigginer with fusion360, it wasn’t easy to design the frame. At first I made a 2D frame to cut with the laser, after asembeling it, we decided on few changes and i designed my frame accordingly.
I drew the first frame in our systems integration box with the hinges that will be press fitted into the side elements.
I copied my frame to create two containers, one where the linear movement and dispensers will be placed and second where motors, PCBs and wires will be hiding. I changed the opening to suit our needs.
Modify > move > choose make a copy and choose distance. I measured our linear system and dispensers before deciding on the distance.
Now here is the part I learned after multiple trials to design the frame.
make a surface interlocking with hinges you created, from Modify > combine > cut > choose targeted object and tool object, the most important thing is to press on keep tool now your new surface is purforated from the exact same place your hinges are located! I manually made those openings bigger with .05mm from each side to make it easier to press and fit all components together.
I repeat this with multiple surfaces, the upper, the side and the lower. I then made dispenser openings.
I uploaded all parts designed by my colleagues and added the glass dispensers.
Below is the final design.
Image below shows Spice Mixer machine after assembling of all parts: dispensers, linear movement, motors and frame.
Circuit Design¶
We decided to use stepper motors since we need to count our steps and make our mixing plate stop at certain places. In my circuit I need the following: 1- Stepper motors. 2- Stepper drivers. 3- Power supply. 4- ESP32 do it microcontroller.
One PCB connected to motors and power supply only.
six PCBs connected to stepper drivers, resistors, and power supply.
As you can see we only had through-hole resistors at the lab so we used a th footprint. we made sure there is no short using the multimeter and i put double sided tape on the bottom befor soldering so the resistor wouldn’t move!
Motor drivers PCBs were attached on the back of each motor where we created a box. they were all connected to the motherboard that was also attached in the same box.
Files Download¶
Spice Mixer Schematic Spice Mixer Board Spice Mixer motherBoard Spice Mixer motherBoard Schematic Spice Mixer Frame