# Create Week9.html and link from index
_Exported on 11/10/2025 at 05:50:21 EST from Cursor (2.0.63)_
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**User**
make a copy of Week8.html called Week9.html and link it from index.html as Assignment 09. include of summary of the group assignment section in week9 copy.html in Week9.html using the images and datasheets in week9groupassignment. include a link for full details to:
https://fab.cba.mit.edu/classes/863.25/people/SaleemAldajani/week9.html#group-assignment
add a highlights section at the top with the images groupassignment-moldingcasting.jpeg and groupassignment-lion.jpeg
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**Cursor**
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Week 9 - Molding & Casting Group Assignment Summary
Week 8 - Output Devices Group Assignment Summary
Measuring Power Consumption of Output Devices
Assignment Overview
This page summarizes the group assignment for Week 8, focusing on measuring power consumption of motors, servos, and stepper motors using adjustable power supplies and precision energy analyzers. We systematically investigated different motor types to understand their performance characteristics and when to use each type.
Group Assignment: Measuring Power Consumption of Output Devices
Measuring power consumption of motors, servos, and stepper motors using adjustable power supplies and precision energy analyzers to understand performance characteristics and when to use each type.
Measurement Setup
We used an adjustable power supply set to 15V and measured quiescent power consumption of 450 mW (0.03 A, where P=IV) before connecting any motors. Power measurements were conducted using the Joulescope (JS220) Precision Energy Analyzer to measure current, voltage, power, charge, and energy in real-time.
Power supply set to 15V for motor testing
Joulescope JS220 Precision Energy Analyzer
Joulescope software interface
Using a potentiometer to change motor speed, we observed that below a certain threshold, the motor doesn't have enough power to spin (no mechanical work, just electrical losses). Above this threshold, speed increases with power. The dI/dt (rate of current change) cannot change instantly—it takes time. The PWM signal from the microcontroller (roughly 50% duty cycle) is smoothed after passing through the motor driver, with more linear behavior on the rising edge than the falling edge.
Motor circuit connections
Complete motor testing setup
50% duty cycle PWM from microcontroller
Smoothed PWM signal after motor driver
Zoomed-in power measurement
Zoomed-out power measurement
Motor Comparison Results
All motors tested at 15V supply, 2A current limit, with the same potentiometer value for comparison. The potentiometer determines speed and power for DC motors, and position for servos.
DC Motors (Voltage-Controlled)
DC Brushed Motor (Large)
Characteristics: Low-speed, high torque, no positional control
Current: 57 mA
Voltage: 14.49 V
Power: 0.8 W
Large DC brushed motor measurement
DC Brushed Motor (Small)
Characteristics: High speed, medium torque, no positional control
Current: 0.34 A
Voltage: 14.47 V
Power: 4.86 W
Small DC brushed motor measurement
Small DC brushed motor operation
DC Stepper Motor (Current-Controlled)
Characteristics: Medium speed, medium torque, zero absolute positional control (relative positioning only)
Current: 2.0 A
Voltage: 10.93 V
Power: 22.33 W
Stepper motor measurement
Stepper motor operation
Servo Motors (5V Supply, Position-Controlled)
All servos tested at 5V supply, 2A current limit. Potentiometer determines position; power consumption remains relatively constant.
Detailed documentation of output device power consumption measurement and motor comparison analysis
Full Assignment Details
For complete details on the Week 8 group assignment, including comprehensive power consumption measurements, detailed motor comparison tables, and complete analysis results, please visit the full assignment page.
We would like to express our sincere gratitude to all members of our section for their invaluable collaboration throughout this group assignment. Your contributions were essential to the success of this comprehensive output device power consumption analysis project.
Collaboration Activities
Power measurement and energy analyzer operation
Motor testing and characterization
Power consumption analysis
Measurement technique documentation
Knowledge Sharing
Joulescope energy analyzer operation and setup
Motor characteristics and power measurement methodologies
Output device selection and application guidelines
Embedded systems power management
This collaborative effort demonstrates the power of teamwork in technical education and hands-on learning. The collective knowledge and shared experiences significantly enhanced our understanding of output device power characteristics and measurement techniques.
References
Output Device Power Analysis Comprehensive guide to measuring and analyzing power consumption of motors and actuators
Energy Analyzer Operation Professional measurement equipment usage and power analysis methodologies
Motor Selection Best practices for selecting appropriate motor types for different applications
Power Management Current limiting, voltage regulation, and power consumption optimization techniques
Embedded Systems Design Guidelines for designing efficient output device interfaces
Ethical AI Use
Documentation of AI tool usage for this week's group assignment summary and website development work.
Week 8 - Output Devices Group Assignment Summary Development
This session covers the development of the Week 8 page for the output devices group assignment, including content structure, technical documentation, and comprehensive coverage of power consumption measurement processes.
Complete development transcript documenting the AI-assisted creation of the Week 8 group assignment page, including content structure, technical documentation, and website development process.
Key AI Activities
Content Structure Creation of comprehensive HTML structure for output device power consumption documentation
Technical Documentation Development of detailed sections covering power measurement and motor comparison techniques
Process Integration Implementation of output device characterization and measurement workflow information
Navigation Integration Addition of Week 8 link to main index page for seamless course navigation
Image Integration Integration of key images and videos from week8groupassignment folder with proper styling and captions
Link Integration Addition of external link to full Week 8 assignment details with proper accessibility attributes
AI Tools Used
Cursor AI Code generation, content structuring, and website development assistance
Technical Content Generation Creation of comprehensive output device power consumption documentation
Website Design Implementation of consistent styling and responsive layout
Content Integration Seamless integration of Week 8 content into the page structure
Media Processing Integration and styling of images and videos with proper responsive layouts
Material benchmarking, SDS review, and casting trials
Week Highlights
Group SDS review and Anthony's lion casting demo guided our material tests.
Prepping silicone and gypsum batches before pour tests.
Anthony's lion casting demo reinforced alignment and venting practices.
Assignment Overview
Our group validated molding workflows by machining wax, pouring silicone tooling, and casting mineral and metal parts while staying aligned with SDS guidance.
Reviewed manufacturer SDS documents for every material before handling.
Measured mix ratios, pot life, and demold windows during silicone and plaster trials.
Documented casting quality, surface finish, and durability to match materials to future needs.
Material Benchmarking Summary
Key findings distilled from the detailed group assignment notes in week9 copy.html.
Mold Materials
Material
Key Specs
Handling Notes
SDS
Mold Star 15 SLOW
1A:1B mix; 50 min pot life; 4 hr demold; Shore A 15.
Low viscosity pour, forgiving for intricate cavities. Ventilate and use nitrile gloves.
Machine wax blanks with >=5 mm wall thickness and add alignment bosses to minimize silicone flash.
Proof mold boxes with water, then pour silicone in a thin stream and tap for about 60 seconds to release bubbles.
Keep oversized pour spouts and witness buttons so we can monitor cure without disturbing the part.
Match casting medium to duty cycle: Hydro-Stone for strength, Drystone for fidelity, and Roto281 for reusable metal prototypes.
SDS Safety Essentials
Condensed reminders - always refer to the full SDS linked below before working.
Mold Star silicones: Part B contains amines; wear nitrile gloves, avoid eye contact, and clean uncured spills with absorbent wipes.
Gypsum products (Hydro-Stone and Drystone): Use N95 masks while weighing powder, protect eyes from alkaline slurry, and never dump set plaster down drains.
Roto281 alloy: Treat as hot metal work - face shield, long sleeves, dry workspace, and staged cooling before handling ingots.
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- Rebuilt `Week9.html` with a top highlights gallery, condensed mold and casting material tables pulling in the Week 9 images and SDS downloads, SDS safety reminders, and a call-to-action that links to the full documentation on the course site.
```191:330:Week9.html
Week Highlights
Group SDS review and Anthony's lion casting demo guided our material tests.
Prepping silicone and gypsum batches before pour tests.
Anthony's lion casting demo reinforced alignment and venting practices.
Assignment Overview
Our group validated molding workflows by machining wax, pouring silicone tooling, and casting mineral and metal parts while staying aligned with SDS guidance.
Reviewed manufacturer SDS documents for every material before handling.
Measured mix ratios, pot life, and demold windows during silicone and plaster trials.
Documented casting quality, surface finish, and durability to match materials to future needs.
Material Benchmarking Summary
Key findings distilled from the detailed group assignment notes in week9 copy.html.
Full Assignment Details
Read the complete documentation - including CAM strategies, tooling notes, and additional cast comparisons - on the course site.
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- Linked the new page from the home index as “Assignment 09” so navigation stays consistent.
```27:35:index.html
Assignment 01 Assignment 02 Assignment 03 Assignment 04 Assignment 05 Assignment 06 Assignment 07 Assignment 08 Assignment 09
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Next steps: preview `Week9.html` in a browser to confirm the new imagery and downloads render as expected, and spot-check external links such as the full Week 9 write-up ([fab.cba.mit.edu Week 9 group assignment](https://fab.cba.mit.edu/classes/863.25/people/SaleemAldajani/week9.html#group-assignment)) for accuracy.
```html
Week Highlights
Group SDS review and Anthony's lion casting demo guided our material tests.
Prepping silicone and gypsum batches before pour tests.
Anthony's lion casting demo reinforced alignment and venting practices.
Assignment Overview
Our group validated molding workflows by machining wax, pouring silicone tooling, and casting mineral and metal parts while staying aligned with SDS guidance.
Reviewed manufacturer SDS documents for every material before handling.
Measured mix ratios, pot life, and demold windows during silicone and plaster trials.
Documented casting quality, surface finish, and durability to match materials to future needs.
Material Benchmarking Summary
Key findings distilled from the detailed group assignment notes in week9 copy.html.
Full Assignment Details
Read the complete documentation - including CAM strategies, tooling notes, and additional cast comparisons - on the course site.
```
```html
Assignment 01 Assignment 02 Assignment 03 Assignment 04 Assignment 05 Assignment 06 Assignment 07 Assignment 08 Assignment 09
```
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**User**
need subsections for: (can be brief and summarize)
Best Practices for Mold-Making Processes
Comparing Mold-Making Processes
Negative vs. Positive Mold Workflows
fix this line to be more descriptive Key findings distilled from the detailed group assignment notes in week9 copy.html. (no need to include the source file since there is a link to the other page for full details)
---
**Cursor**
```html
Week 9 - Molding & Casting Group Assignment Summary
Week 9 - Molding & Casting Group Assignment
Material benchmarking, SDS review, and casting trials
Week Highlights
Group SDS review and Anthony's lion casting demo guided our material tests.
Prepping silicone and gypsum batches before pour tests.
Anthony's lion casting demo reinforced alignment and venting practices.
Assignment Overview
Our group validated molding workflows by machining wax, pouring silicone tooling, and casting mineral and metal parts while staying aligned with SDS guidance.
Reviewed manufacturer SDS documents for every material before handling.
Measured mix ratios, pot life, and demold windows during silicone and plaster trials.
Documented casting quality, surface finish, and durability to match materials to future needs.
Material Benchmarking Summary
Key takeaways from our molding and casting comparison work this week.
Mold Materials
Material
Key Specs
Handling Notes
SDS
Mold Star 15 SLOW
1A:1B mix; 50 min pot life; 4 hr demold; Shore A 15.
Low viscosity pour, forgiving for intricate cavities. Ventilate and use nitrile gloves.
Machine wax blanks with >=5 mm wall thickness and add alignment bosses to minimize silicone flash.
Proof mold boxes with water, then pour silicone in a thin stream and tap for about 60 seconds to release bubbles.
Keep oversized pour spouts and witness buttons so we can monitor cure without disturbing the part.
Match casting medium to duty cycle: Hydro-Stone for strength, Drystone for fidelity, and Roto281 for reusable metal prototypes.
Best Practices for Mold-Making Processes
Prep wax with three-point hot glue fixturing and maintain thin beeswax skins for easy cleanup.
Size registration bosses intentionally so silicone halves seat without flash or misalignment.
Mix silicones by pouring the heavier component first, scrape walls, and pour in a steady ribbon.
Use oversized sprues, vents, and clamp pressure that suits each casting medium.
Comparing Mold-Making Processes
3D-printed tooling: fast turnaround for complex shapes, but needs sealing to hide layer lines.
CNC-machined wax: best surface finish and registration, trades for longer CAM prep.
Hand-sculpted wax: quick for simple forms, limited to low-temperature casting media.
Negative vs. Positive Mold Workflows
Direct negative molds: cast straight into rigid tooling—great when parts have easy draft and tolerate demolding forces.
Positive-to-negative sequences: machine or print a master, then pour silicone inserts for flexible release and repeatability.
Choose flexible tooling whenever undercuts, delicate surfaces, or repeated pours are expected.
SDS Safety Essentials
Condensed reminders - always refer to the full SDS linked below before working.
Mold Star silicones: Part B contains amines; wear nitrile gloves, avoid eye contact, and clean uncured spills with absorbent wipes.
Gypsum products (Hydro-Stone and Drystone): Use N95 masks while weighing powder, protect eyes from alkaline slurry, and never dump set plaster down drains.
Roto281 alloy: Treat as hot metal work - face shield, long sleeves, dry workspace, and staged cooling before handling ingots.
Thanks to Anthony for the lion casting demo and safety walk-through, and to the team for calibrating mix ratios and documenting every trial.
```
- Refined the summary intro to highlight the Week 9 molding and casting comparison work without referencing internal files.
- Added concise subsections covering best practices, mold-making process comparisons, and negative vs. positive workflow guidance.
Looks good. Preview `Week9.html` in a browser to confirm the new sections read cleanly and align with the external Week 9 reference.
