Week 08 Electronics Production

Group Assignment

We used smaller CNC machine than last week. And the end-mill is very thin like a hair. So one of the most important thing is to protect the mill. Especially 2 situations. One is setting up, we need to be careful when put the end mill on the machine if I dropped it, easily it would be broken. So I keep the cover on until the set up done. The second is configuration of milling, speed and cut depth should not be too much.

make and test the development board that you designed to interact and communicate with an embedded microcontroller
extra credit: make it with another process

I changed PCB design as below and milled for my final project.(original data: sch / pcb)
Milled a PCB
And soldering.

I did PCB design for the assignment of week6 as below.
Based on advice from instructors I needed to change it below 2 points.
- I did not think about DRC (design rule checking) at all. For example the width of the line. Now I confirmed such rules in the group assignment this week.
- To make lines assignment simple, I put vertical connectors. But this is not durable.
- I just made PCB design for test something, but it would be better for my final project.
For changing my PCB design, I checked VCC and communication io of my final project devices. At this moment I am going to use 3 devices as below;
- Force sensing: FSR402 / 5V / Analog
- Acceleration sensing: Sensor with MMA8452Q/ 3.3V / I2C
- Sound: DFPlayer mini / 5V / UART
xiao2040 has all of io pins above, so I put xiao2040 as the controller of my board.
I learned from instructor Adrian’s work that the pattern line can go under the controller, it made design simple.
As a result I designed as below;
Then extracted pattern and edge line (.svg) for milling

Imported the svg file above. And select only pattern for setting. Then start settings in the tool path window.
Tool path setting is similar to week7 but this time "Pocket" setting is required for patterns. Select "Pocket" -> "Tool" window
Settings as follows;
- end mill size: 0.3mm
- cut speed 150 mm/min
Number of path and cut depth setting.

Settings as follows;
- cut depth 0.2mm
- Number of cut 1
Completed pattern cut settings, and I can see the image of the milling.
Export .rol file (original file)

Select only edge line for setting. Then start settings in the tool path window.
"Contour" cut settings for edge. Select "Contour" -> "Tool" window to change the tool parameters
- end mill size: 1mm
- cut speed 150 mm/min
Number of path and cut depth setting.

Settings as follows;
- cut depth 0.4mm
- Number of cut 4
Completed pattern cut settings, and I can see the image of the milling.
Export .rol file (original file)

Controlling software "Roland VPanel". I can operate the software with the machine being connected the PC and power on.
Put the new board on with sticky tape. So that the board is fixed during the work.
Set end mill (0. 3mm for pattern, 1mm for edge)
Bring the spindle by clicking triangles (red for x, green for y) to the left bottom edge of the board on the stage. Then set xy origin.
For setting z=0, put the touch sensor on the board.

And start z=0 detection on VPanel
x10
x10
- Origin setting complete x10
- Then import .rol file to work start
x10

Used Arduino IDE for editing and uploading code same as week 4
My board has an LED out of the controller. I tried to blink the LED with below sketch.

void setup() {
    pinMode( 2, OUTPUT );
}
void loop() {
    digitalWrite( 2, HIGH );
    delay(100);
    digitalWrite( 2, LOW );
    delay(300);
}

- Successfully worked.

Soldering is simply difficult, but I managed to make my board and the LED worked as expected.
Device worked, but soldering looks not good. So I need to keep practicing.
No debugging around code, continuity test with multimeter was fine, but added solder some as my soldering looked bad.

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