Clemson UniversityDepartment of Mechanical Engineering

ME8700-Advanced Design Methodology

Design of a platform for Lab-on-a-Chip devices for secure Microfluidic experimentations

By:Monsur IslamSunnykumar PatelShyamal Satodia

Design of a platform for Lab-on-a-Chip devices for secure experimentation

Problem Statement:Microfluidics and Lab-on-a-chip is one of the most researched areas in scientific community in present days due to its wide range of application. But a little problem that the microfluidics researcher often ignore is that during the experiment the microfluidic device sometimes gets displaced or interrupted due to the movement of the tubes attached with the device or the handling the equipment (e.g. syringe pump, power source). Hence sometimes expected results don't come out and consumes more time to perform the experiment. Hence, our idea is to design a platform where we can place our microfluidic chips securely and perform experiments without any external disturbance.

Objective:Our idea is to design a platform where we can place our microfluidic chips securely and perform experiments without any external disturbance.

Criteria

Robust structure

Stable enough with the handling of other equipment

Flexible with dimension of the chips - 45×25 mm

Safe interaction of chip with the platform

Flexible with the tubing at the inlet and outlet of the chip

Provision for other accessories

Constraint

The displacement of the chip should not be greater than 0.5mm

Low Cost (not more than $70)

The top of the platform should not have any extrusion higher than 10 mm

Box size - 150×150×80 mm

Should have place to manoeuvre the microscope eyepieces over the platform (3mm on either sides of the chip)

EXISTING SETUP

A stable, easy to handle Platform for microfluidic experiments

Safety

Environment

Electrically Insulated

No contamination

User

Cost

Installation

Manufacturing

Materials

Maintenance

Repair

Replacement

Flexible

Flexible with the size of the chip Easy to Handle

Easy replacement of

chip

Easy to clean

Easy to move

Connections

Electrical Connection

Connection with chip

Connection with source

Fluidic Connection

Inlet connection

Outlet connection

Robust structure

Chip steadiness

Platform rigidity

Vibration resistance

OBJECTIVE TREE

MORPHOLOGICAL CHART

SOLUTIONS

Solution 1

Solution 2

Solution 3

Solution 4

Solution 5

Re-evaluating the solutions• We applied different criteria to draw two best solutions.• The criteria which are violated by the solutions are:

1. Vibration resistance – Solution 3 and Solution 5. Spring may undergo displacement if the vibrational force is very high. – Solution 4. The rubber supports cannot restrict the movement of chip. The chip would displace more than 0.5mm. Also, wood is a lighter material and it wouldn’t resist the displacement of the assembly.

Re-evaluating the solutions (continue..)

2. Cost – Solution 3Carbon fiber, though light and very suitable, cannot be used because it is very expensive.

3. Handling of the structure – Solution 4Since the box is detachable it becomes time consuming and hectic to change chips

frequently. Also, detachable box might require it’s own clamping.

• After eliminating two solutions, we are left with Solution 1 and Solution 2.

Solution 1 – A steel fixed box-type structure with bolt mechanism. Solution 2 – A steel fixed plate platform with clamping mechanism.

• Further we compared the solutions using weighted analysis method to get the best result.

Rigidity of platform

Damping Flexibility of the chip Flexibility of the structure

Cost

Solution 1 9 8 9 8 8

Solution 2 7 9 9 8 8

Weight 10 10 8 6 6

Total

Solution 1 90+80+72+48+48=338

Solution 2 70+90+72+48+=320

WEIGHTED ANALYSIS METHOD

Solution 1 is the best among all.

DESIGN

1.Chip Holder 1 2.Chip Holder 2

3.Base Plate (Steel)

DESIGN (Continue..)

4.PCB with electric connections 5.Pipe holder

6.Aluminum rod

DESIGN (Continue..)

Final assembly

4

6

5

3

1,2

SOLUTION 1

• The overall cost of the assembly will be around 45-50 $ inclusive of the manufacturing cost. ( ½ ф – 1 feet Aluminum rod for legs – 3.19$ ) ( 1’ X 0.5’ X 7/8” Low Carbon Steel Plate - 9.29$ ) ( 0.5’ X 0.5’ X 6’ Acrylic Plate – 4.46$ ) ( Fasteners – 2$ ) (All the above rates are available from www.mcmaster.com )

• Since, we are using the chip holders, protrusion from the top of the platform would be not more than 5 mm.

• The size of the assembly is within limit as it is coming around 122mm X 62mm X 72mm.

• Since, the stand for holding the pipes is stand alone, enough space is available to maneuver eyepiece over the chip.

FULFILMENT OF CONSTRAINTS AND CRITERIA

LEARNING & INFERENCES

1. There are not many instruments available in the market for microfluidic experiments, we have attempted a new design incorporating design theories like Pahl and Beitz, Weighted Method, Pairwise Comparison for comparing multiple solution to the design problem posed.

2. More improvements can be brought by changing the material of construction.

3. Initial proposed design was eliminated as it was not providing flexibility with the size of chip.

4. Lastly, as this project serves as a tool in microfluidic research, we got to learn something about the microfluidics world.

THANK YOU!