P08028: Magnet Centering Device
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Establish Target Specifications

List of Metrics

The table below presents the metrics, or engineering specifications, that are incorporated in our design which illustrates the number times a part is used in our process

List of Metrics
Metric No. Metric Used throughout process Units
1 Linear Stage 1 micron
2 Rotary Stage 3 degree
3 Measuring physical diameter of bushing 2 micron
4 Hall effect sensor 2 Volts
5 Vacuum 4 KPa
6 Magnet holder (tolerance) 4 micron
7 Bushing holder (tolerance) 4 micron

The metrics, or engineering specifications, that you created in the preceding list should be directly related to the customer needs. In other words, if you have created an engineering specification, it should have some relationship to a need imposed by the customer or the marketplace. Use the table below to map your customer needs against the metrics (or engineering specifications). In many design and product development circles, the rows along the left is often referred to as the voice of the customer, while the columns across the top are often referred to as the voice of the engineer.

Customer Needs as Related to Engineering Metrics Matrix
Needs and Metrics Linear Stage Rotary Stage Measuring physical diameter of bushing Hall effect sensor Vacuum Magnet holder (tolerance) Bushing holder (tolerance)
Centering magnetic field x x x x x x x
Adhering magnet to the bushings x x
Adaptable x x x x x
Cost within budget x x x x
User friendly x x x x
Maintenance and calibration x x x x x x x
Time to center magnet x x x
Automated x x x x
Portable
Dampening x
Balanced Assembly

Collect Competitive Benchmarking Information

The benchmarking portion of our project consider the test rig of the current rig used to center magnets. This device was not intended to center magnets therefore the centering process and procedure was incorporated into the test rig. The first benchmark was to determine the viability of using a vacuum to hold certain components of our device. Secondly, a benchmark was performed on laser sensors. This benchmark was done to determine if laser exist to the precision that is needed for this project. Thirdly, the last benchmark was performed on the portion of our project that dealt with the motion aspect. This involved the linear and rotary stages.

Benchmark 1 - Vacuum Chucks
A vacuum chuck was an idea that uses compressed air as a mean to produce a vacuum intended to hold a component, in our project a magnet and bushing. Research was done in determining if a vacuum could hold the components and not has the components move or be shifted during the centering process. The suction pads of the type PFYN 95 VU1 generate very high and reliable holding force for precise positioning. They are made of hard-wearing a crack-resistant Vulkollan. The vacuum is generated by a compact ejector with blow-off valve, non-return valve and automatic air saver. Mounted on an ABB industrial robot, this vacuum spider offers fast, safe and precise handling of (glass) parts together with cheap operation and high technical availability. Compnay - Schmalz Vacuum Gripper System. The illustration below provides an idea of what could be held using a compressed air vacuum.
 A Vacuum chuck used by the glass industry to insure a reiable and cheap device

A Vacuum chuck used by the glass industry to insure a reiable and cheap device

Benchmark 2 - Laser Sensor
The second benchmark was done on devices that use laser sensors to determine the position and or diameters of objects. It was determined that laser sensors are used for microelectronics and have high resolution and repeatability which is need for our project to be reliable and automated. The Acuity company uses their laser sensors for the manufacturing and production of semiconductor wafers. AR200 laser measurement sensors are widely used by U.S. and international fabrication equipment designers to monitor and control the location of silicon wafers throughout the fabrication process.
 Laser sensor being used in the manufacturing of semiconductor wafers

Laser sensor being used in the manufacturing of semiconductor wafers

Table below compares different companies with there prices and specs on laser sensor -
 Laser Sensor Companies

Laser Sensor Companies

Benchmark 3 - Linear /Rotary Stages
The linear stages are a necessity for this project, the magnet and bushing need to be moved to their magnetic and physical center, respectively. The portion of the benchmarking of the linear stages is to find a device that could move the components in small increments while being repeatable and accurate or have high resolution. Typical applications include semiconductor wafer inspection, sensor test and calibration, laser machining and ultra-precision assembly.
 Linear Stages being used in semiconductor manufacturing

Linear Stages being used in semiconductor manufacturing

Table below compares different companies with there prices and specs on linear stages -
 Linear Stages Companies

Linear Stages Companies

Table below compares different companies with there prices and specs on rotary stages -
 Rotary Stages Companies

Rotary Stages Companies

Competitive Benchmarking Matrix
Metric No. Need Nos. Metric Importance Units Benchmark 1 Value Benchmark 2 Value Benchmark 3 Value
1 Need 1,1 Linear Stages 5 micron 25 1 .01
2 Need 1,2 Rotary Stage 5 micron 30 1 3
3 Need 2 Vacuum Chuck 4 kPa 13 54 94
4 Need 3 Laser Sensor 4 micron 0.9 1 10

Set Ideal and Marginally Acceptable Target Values

List of Metrics
Metric No. Need Nos. Metric Importance Units Marginal value Ideal Value
1 Need 1,1 Linear/Rotary Stages - Accuracy 3 % 5 1
2 Need 1,2 Linear/Rotary Stages - Repeatability 5 micron 3 1
3 Need 1,3 Linear/Rotary Stages - Resolution 5 micron 3 1
4 Need 2,1 Laser Sensor - Accuracy 5 micron 1 0.1
5 Need 2,2 Laser - Size 4 cubic cm 750 600
6 Need 3,1 Vacuum Chuck - Holding force 4 kPa 13 54

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