5‐Concept evaluation and product architecture - V-Div-26-27-Odd/REPO-2 GitHub Wiki
PUGH CHART
Assign Weights to the Objectives
| Objectives | Weights |
|---|---|
| Safety | 7 |
| user friendly | 8 |
| Accuracy | 5 |
| Cost | 8 |
Pugh Chart for Alternative Designs
| Design Objectives | Weights | Design 1 | Design 2 | Design 3 | Design 4 | Design 5 |
|---|---|---|---|---|---|---|
| Accuracy | 5 | + | Datum | + | 0 | ++ |
| Safety | 7 | + | Datum | 0 | ++ | - |
| Cost | 8 | 0 | Datum | - | + | + |
| user friendly | 8 | - | Datum | - | - | + |
| Score (+) | 12 | 0 | 21 | 22 | 26 | |
| Score (-) | 8 | 0 | 8 | 11 | 7 | |
| Total | +4 | 0 | +13 | +11 | +19 |
5.1 JUSTIFICATIONS FOR SCORE GIVEN
| Design No. | Objective | Score Allocated | Justification for the Score |
|---|---|---|---|
| 1 | Safety | +7 | The hopper and servo flap reduce direct contact with components hence |
| User friendly | -8 | The conveyor and camera needs more programming making it complex | |
| Accuracy | +5 | IR sensor and ESP32Cam gives reasonable accuracy | |
| Cost | 0 | Same cost as that of datum | |
| 2 | Safety | Datum | Considered as a reference |
| user friendly | Datum | Considered as a reference | |
| Accuracy | Datum | Considered as a reference | |
| Cost | Datum | Considered as a reference | |
| 3 | Safety | 0 | Sensors and machines have almost similar mechanism as of reference |
| user friendly | ++8 | Automatic detection makes the machine simple to operate | |
| Accuracy | ++5 | FSR + Web cam provide better identification and measurement | |
| Cost | -8 | The step belt, webcam, slider increases overall cost | |
| 4 | Safety | ++7 | Here the sensors are of no contact hence the safest option |
| user friendly | -8 | The star wheel mechanism needs more setup compared to reference | |
| Accuracy | 0 | Proximity sensors provide accuracy similar to that of reference | |
| Cost | +8 | The simple tray and basic camera keep the overall cost relatively low | |
| 5 | safety | -7 | Comparatively more complex structure |
| user friendly | +8 | easy movement of components | |
| Accuracy | ++5 | rotating disc make positioning easy | |
| Cost | +8 | affordable than the reference taken |
5.2 SELECTED DESIGN
MECHANISMS
- Components are fed from hopper using DC geared motor
- Sensor detects each component and sends signal
- Camera identifies the component type
- Rotating disc rotates and position the object at correct place using stepper motor
- Components falls into respective bin using servo flap
5.3 PRODUCT ARCHITECTURE
FUNCTION CLUSTERING
Subsystem List
| SL.# No. | Subsystem |
|---|---|
| 1 | Handling unit |
| 2 | Sensing and computing unit |
| 3 | Sorting unit |
| 4 | Storage unit |
5.4 INTERACTION BETWEEN SUBSYSTEMS
Subsystem 1: Handling Unit
| Interaction Type | Subsystem 2 (Sensing & Computing) | Subsystem 3 (Sorting) | Interaction Details |
|---|---|---|---|
| Spatial | yes | - | Components moves to sensing unit |
| Data | - | - | |
| Material | yes | - | Metals/semiconductor interacts with sensors |
Subsystem 2: Sensing and Computing Unit
| Interaction Type | Subsystem 1 (Handling) | Subsystem 3 (Sorting) | Interaction Details |
|---|---|---|---|
| Spatial | - | - | |
| Data | yes | yes | Sensing unit sends signal to control handling |
| Material | - | yes | Sensing unit sends component category to sorting |
Subsystem 3: Sorting Unit
| Interaction Type | Subsystem 1 (Handling) | Subsystem 2 (Sensing & Computing) | Interaction Details |
|---|---|---|---|
| Spatial | - | - | No direct contact between sorting and handling units |
| Data | - | - | No direct reverse interaction is required |
| Material | - | - |
Subsystem 4: Storage Unit
| Interaction Type | Subsystem 1 (Handling) | Subsystem 2 (Sensing & Computing) | Subsystem 3 (Sorting) | Interaction Details |
|---|---|---|---|---|
| Spatial | - | - | yes | Positioned directly beneath or adjacent to sorting flaps/chutes |
| Data | - | - | - | No direct reverse data signal required |
| Material | - | - | yes | Receives and holds segregated components from the sorting unit |