LOC Design with CADLecture Slides

Learning ObjectivesLearn creating LOC part file using

Solidworks

Learn to do basic dimensioning for the LOC part file

Lab-on-a-Chip Designs

For this class you will create two LOC designs per team sequentially through the semester.

The two designs are created to adapt your design ideas to two different chipholder designs and explore different design approaches 4-Hole Chipholder 3-Hole Chipholder

The Chip Requirements document on the Nano Lab Documents Page describes the requirements of the two designs.

Leveraging Lab 1 Experiences

What went wrong or did not work well?

How can this “generic benchmark” be improved upon?

What prevents good performance (e.g., dirt, scratches, poor seals, channel/well proximity, well geometry, etc.) and how can this knowledge be used to create a better design and better practices when testing the design?

Use your observations! Be creative! Use multiple approaches.

Your design should be a marriage of function and form!

LOC DesignGoals

Optimize fluid flow from staging to detection and waste wells

Completely fill the detection well for examination

Design choices Number of wells and channels Shapes of wells and channels Location and size of wells

LOC in Chipholder

LOC Manufacturing Constraints

LOC designs will be milled from an acrylic wafer The milling machine will be using a very small circular bit.

Should not create any internal sharp corners since a circular bit cannot make that shape.

For such features, round the internal corners with a radius of curvature of at least 200 microns.

Also no channel or opening can be smaller than 300 microns.

Extruded part file should be 1/8” (5000 microns) thick with wells and channels 200 microns deep. Put your group letter on one side of the chip for identification.

Round the internal corners with a radius of curvature of at least 200 μm

LOC Manufacturing Constraints –Internal corners

Deliverables

Design DeliverablesEach team will provide two chip designs for the LOC device – One design for each chipholder

 

Initial Sketch Design

Submission for the 1st chip

Preliminary 1st

design

1st Chip Design

Submission

2nd Chip Design Submission

Hand-drawn sketch RequiredNot

requiredNot required Not required

Solidworks Deliverable

Not required

Dimensioned

Part File to GTA

DimensionedPart File to GTA

1.Printout of dimensioned drawings2. Send Solidworks part

file to GTA

Operational Process Not requiredNot

requiredPer Chip

Requirements Revised

Calculations Not requiredDetection

well Volume

Per Chip Requirements Per Chip Reqts. Doc.

LOC Specifications Chip Diameter – 50800 μm

Chip Thickness – 5000 μm

Depth of ALL Features – 200 μm

Channel widths – 300 μm – 400 μm

Detection Well Volume – 3 μl

Round all sharp corners!

Refer to Project Documentation, Checklist, and Deliverables document

Preliminary Design

Solidworks Part File emailed to GTA, due per website.

Includes:

Use of 4-hole chip holder design (seed file) to ensure well alignment

Dimensioned Part File

Calculation of detection well volume

Include separate simple logo to identify your chip

Instructional Team will provide feedback of the designs

Part file (.SLDPRT) Submission

Send one part file per design to your GTA

CONVERT UNITS TO INCHES

USE FILE NAMING CONVENTION FOR EACH FILE

EXAMPLE: “LOC_SP15_B_DESIGN1.SLDPRT”

LAB ON CHIP Semester

And YearGROUP CHIP NUMBER

1st Design Submission Based on the feedback from the

preliminary design by your GTA Send the part files (.SLDPRT) to TA (insure

proper extrusion) Operational Process Calculations for all features per Chip

Requirements document

2nd Design Submission Based on the revisions suggested in the 1st

design Should be drawn on 3 hole chip holder design (seed file) to

ensure alignment. Dimensioned Chip Design drawing file with top

view scaled up to 3:1. Send the part files (.SLDPRT) to TA (insure proper

extrusion) Revised Operational Process Calculations for all features per Chip

Requirements document

Solidworks Part File

Use the 4 Hole (1st Design) and 3 Hole (2nd Design) chipholder templates to create your design.

The templates are in the seed files on the website (dimensions set to microns and has chipholder geometry)

Chip Holder Design with Chip

Solidworks Steps

Go to lab webpage and open Seed File from Solidworks

Extrude circular shape back into sheet 5000 microns

Put sketch plane on circular shape

Turn on visibility of chipholder access holes

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Solidworks steps (cont.)Design your features using the access holes

locations. Put a simple team logo. Connect wells with channels.

Dimension the size all features

Finish sketch, features and logo

Extrude the features into the sheet 200 microns.

Send part file to GTA with correct naming convention.

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SolidWorks: Dimensions

Dimensional Constraints can be added using the Smart Dimension Button

1. Click on the entity2. Move cursor off object3. Click once more to

place dimension

When Constraints are applied the following dialog box will appear displaying• Dimension Name• Editable Dimension

Value• Options (direction,

etc.)

SolidWorks: Dimension Options

Or even 2 points as long as the correct direction is

chosen ( the Smart Dimension tool shows

options when moving the mouse)

Dimensions can be added between 2 lines by selecting the lines

sequentially

Between a point and a line

SolidWorks: Circles and Arcs

Circles or Arcs can be dimensioned by the

diameter (Ø) or radius (R)

A circle can be located by its center point by

constraining both the x and y directions

SolidWorks: Angular Dimensions

Angular Constraints can be added by clicking one line and then the other line. SolidWorks

will automatically assume angular constraint.

Generic Dimensioned Design

Locate dimensions forease of readability

Provide dimensions for sizeand shape of wells and sizeof channels

Team letter only needsoverall width and lengthdimension