Transcript Document 7350009
Product Design Process
By Team Strider
Table of Contents
• Introduction • Customer Needs • Benchmarking • Programming Concepts • Structural/Lift Concepts • Propulsion Concepts • Concept Integration • Gantt Chart/Conclusion
Introduction
• Ultimate goal Design and fabrication of an autonomous hovercraft • Product Development Process Two phases completed Benchmarking & Customer Needs Concept Generation
Introduction (continued)
Benchmarking & Customer Needs Results: – Several existing models assessed – Company owner interviewed
Introduction (continued)
Concept Generation: • Hovercraft subsystems divided into three groups • Structure and Lift • Propulsion and Power • Instrumentation & Control
Introduction (continued)
Assessment: • Pugh Matrix • Concept scoring matrix
Customer Needs
By Team Strider
Customer Needs Evaluation
• Consulted Bryan Phillips, owner/operator of Amphibious Marine, a commercial hovercraft manufacturing company • Amphibious Marine builds hovercraft used in industry as well as recreation, for private and government customers.
Important • Basic functionality • Reliability Relatively Unimportant • Costs • Adaptability
Benchmarking
By Team Strider
The Benchmarking Process
• Evaluate our competition to obtain knowledge • Comparative analysis of competitors products.
• Process, methods, and service performance against competitors.
Existing Products
Specifications
Power:
4.8 to 8.4 volt 600mA/Hr and greater capacity (mA/Hr) NiCad, MiMH or Lipoly batteries.
Runs on 4, 6, or 7 cell batteries.
Propellers:
Thrust:
3 inch (0.0762 m) ducted fan
Lift:
3 inch (0.0762 m) ducted fan
Motors:
280 size
Skirt:
Black Rip-stop Vinyl
Operating Surface:
Water or Land (will float off of hover and return to full hover) Will transition from water to land
Radio Requirements:
2, 3 or 4 channel land based RC systems ( as used in RC cars and boats)
Speed Controller Requirements:
5 Amp 7-8 cell Electronic Speed Controller (ESC). Can use ILC model for 2 channel control with forward/reverse thrust
Craft size:
Length: 18 inches (0.4572 m) Width: 8 inches (0.2032 m) Height: 5 inches (0.127 m)
Craft Weight:
17 ounces (0.481941893 kg) loaded with battery, ESC and radio equipment (as in our combo)
Max speed:
30 km/h (8.33 m/s)
Range:
¼ mile (402.33600 m)
Product SR.N5
Figure 2 Reference 1 Existing Products
Specifications
Craft size:
Length: 26 inches (0.6604 m) Width: 20 inches (0.508 m) Height: 11 inches (0.2794 m)
Craft Weight:
2.4 Pounds (1.08862169 kg) loaded with battery and radio equipment (as in our combo)
Power:
7.2 or 8.4 volt 1700mA/Hr and greater capacity (mA/Hr) NiCad RC car battery.
Motors:
400 size
Propellers:
Thrust:
6 inch (0.1524 m)
Lift:
4 inch ducted fan (.1016 m)
Skirt:
Black Rip-stop Vinyl
Operating Surface:
Water or Land (will float off of hover and return to full hover) Will transition from water to land
Hover Height:
1.5 inches (0.0381 m) (no additional load other than kit as built with 6 cell NiCad)
Speed:
10-25 MPH (4.4704 - 11.17600 m/s) depending on terrain and operating conditions
Radio Requirements:
2 or 4 channel land based RC systems ( as used in RC cars and boats)
Speed Controller Requirements:
Electronic Speed Controller (ESC) 20 Amp 7-8 cell
Product HoverDart Figure 3 Reference 1 Existing Products
Specifications
Craft size:
Length: 24 inches (0.6096 m) Width: 16 inches (0.4064 m) Height: 9 inches (0.2286 m) Craft Weight: 2.3 Pounds (1.04326245 kilograms) loaded with battery and radio equipment (as supplied in our combo)
Power:
7.2 or 8.4 volt 1700mA/Hr and greater capacity (mA/Hr) NiCad RC car battery. Can also be used with LiPoly and NiHM battery packs.
Motor:
480 size
Propellers:
6 inch (0.1524 m), Ducted
Skirt:
Black Rip-stop Vinyl
Operating Surface:
Water or Land (will float off of hover and return to full hover) Will transition from water to land
Hover Height:
1.5 inches (0.0381 m) (no additional load other than kit as built with 6 cell NiCad)
Radio Requirements:
2 channel land based RC systems ( as used in RC cars and boats)
Speed Controller Requirements:
Electronic Speed Controller (ESC) 20 Amp 7-8 cell
Issues with Current Products • • • • Speed – Products rarely exceed the 30 – 35 km/h barrier – Can be overcome by: • Increasing Size and Number of Fans • Minimizing the Weight/ Size of Product Maneuverability – Reduced Performance in Reverse – Can be overcome by: • Implementing a Dual Fan Propulsion Assembly Safety – Exposed Fan Blades – Can be overcome by: • Protective Screens Placed at Ends of Ducted Fans Durability – Brittle and Vulnerable Components – Can be overcome by: • Additional Layer of Rubber Applied to the Body
Project Specifications • Circular Base: • Height: • Weight: • Payload Capacity: • Volume: • Footprint: • Top Speed: 13 inches 3.5 inches < 2.5 lbs.
> 5 lbs.
618.5 cubic inches 176.71 square inches 30 km/h
Programming Concepts
Hovercraft Programming Concept Design By Team Strider’s Programming Team
Introduction to Concept Generation
• • • • • • • • Navigation: Most important. The hovercraft’s ability to navigate the course based upon sensor location and types of sensors accounts for 25% of the weight. It is most important that the hovercraft be able to navigate the course and complete the main objective Sensitivity: Weighted at 20%.
Without perfectly functioning sensors, there would be no hovercraft, being that malfunction in the hovercrafts sensors would create a significant handicap in its mobility. It would interfere with the programming and therefore, make the hovercraft incapable of follow commands. Durability: Weighted at 20%, it focuses on the durability of the sensors. It is imperative that the sensors are durable for the reasons mentioned above. So when selecting the final concept we had to account for the placement of the sensor that will allow them to last and not to be exposed to collisions. Ability to be integrated: Integration was weighted at 15%.
When selecting a concept we analyzed which concept would have the ability to facilitate our integration phase without interfering in any way with other subsystems.
Introduction to Concept Generation
• • • • • • Versatility: Versatility was weighted at 10%.
We had to focus on those concepts that would enable us to make the programming of the hovercraft system more versatile. We are mainly searching for versatility in the programming section that makes the craft adaptable. This versatility will somewhat depend on the sensors placement on our hovercraft. Sensor balance: The sensor balance accounts for 5% of the weight. The sensor balance deals with equal distribution of the sensors placement accounting for every side of the hovercraft. Though ballasts could be used to counter any weight inconsistencies, it is preferable not to need them and keep weight down. When we focused on the criteria, we focused on the concept that would provide us with the most balance.
Sensor stability: The stability of the sensor also accounted for 5% of the weight. It is important that the sensors are positioned on the hovercraft on a spot where they would not fall off or be subjected to movement, and risk the chance of being ruined, or displaced.
Concept Generation
Concept #2 Concept #1
The Concepts (continued)
Concept #4 Concept #3
The Concepts (continued)
Concept #6 Concept #5
The Concepts (continued)
Concept #7
Weighted Criteria
Concept 1 Concept 2 Concept 3 Concept 4 Concept 5 Concept 6 Concept 7 Sensor Balance (5%) 6 1 5 3 2 4 7 Durability (20%) Sensitivity (20%) Versatility (10%) Sensor Stability (5%) 3 4 1 6 7 5 2 7 3 2 4 5 6 1 7 3 2 4 5 6 1 3 1 1 6 7 5 2 Ability to be Integrated (15%) 1 Navigation of Course (25%) 4 5 6 1 2 4 3 3 6 2 7 7 5
Pugh Chart
Balance Durability Concept 1 Concept 2 Concept 3 Concept 4 Concept 5 Concept 6 Concept 7 * * 0 + 0 + 0 + - 0 - 0 - + Sensitivity Versatility Stability Compatibili ty * * * * - - + - - - + - - - + - 0 + 0 0 + + 0 0 + + 0 0
Concept Selection
*Images care of Microsoft Office Clipart
Concept Selection (continued)
CONCEPT XY!!!!
*Images care of Microsoft Office Clipart
Structural/Lift Concepts
Hovercraft Programming Concept Design By Team Strider’s Structural/Lift Team
Figure 1
• Frisbee-like circular base • Centrifugal fan
Figure 2
• Square, styrofoam base • Piston based air pump • Distributed arrangement
Structure/Lift – Figure 3
•Thin Metal or Balsa wood base with axial symmetry •Axial fan •Dispersed load
Structure/Lift Pugh Chart
Strength Durability Balance Ease of Construction Availability of materials Cost Safety Weight Size Payload assisting Sum +'s Sum 0's Sum -'s Net Score Rank Continue ?
No 2 2 6 -4 + + 0 0 0 0 0 0 10 0 0 0 0 0 0 0 0 0 + + 3 2 5 -2 0 + 0 0 0 0 4 6 -6 0 0 + 1 6 3 -2 0 0 0 0 0 0 + 2 5 3 -1 0 0 + 0 0 0 Yes No No No No Yes 0 0 0 0 10 0 0 0 0 0 0 0 0 0
Structure/Lift Pugh Chart
Strength Durability Balance Ease of Construction Availability of materials Cost Safety Weight Size Payload assisting Sum +'s Sum 0's Sum -'s Net Score Rank Continue ?
0 + 0 + + 4 2 4 0 + No No 0 + 0 + 0 3 4 3 0 + 0 0 + 0 + 2 3 5 -3 0 0 + 0 + 0 3 5 2 1 + 0 0 0 0 0 0 0 0 0 0 10 0 0 0 0 0 0 0 1 9 -8 0 0 0 0 0 0 0 0 10 0 0 0 0 0 0 0 0 0 0 4 6 -6 0 0 0 0 0 0 0 0 10 0 0 0 0 0 No No Yes No Yes
All-Terrain Vehicle
United States Patent 6845833 • Rectangular/trapezoidal shape with a main cabin • Lift engine supplies lift to the backside of the main body. Separate from propel engine.
• Incorporated various structural shapes in our concept generation.
• Assumed the lift engine to be separate from the propel engine.
Vehicle Assisting Fabric
United States Patent 6955192 • External fabric utilized to support vehicle in snow, sand, or mud.
• When using fragile materials, such as Styrofoam, for the base, rubberized spray can be applied to reinforce the structure.
Air Cushion Vessel
United States Patent 6672234 • Weight supported by varying elements such as surfaces, different volumes, air cushions, and pressure.
• Size/arrangement are designed to achieve the best effect for lift and motion.
• Incorporated concepts like size of volume and need for strong powered lift fan to provide air cushion.
• Recognized need for distributed arrangement to create balance for lift and motion.
Propulsion/Power Concepts
Hovercraft Programming Concept Design By Team Strider’s Propulsion/Power Team
Propulsion Concepts
Figure 4 Reference 2 Hovercraft Concept Design Rear mount Propulsion with rear mount steering fan
Propulsion Concepts (continued)
Hovercraft Concept Design Dual Propulsion/Steer motor Single lift motor Figure 5 Reference 2
Propulsion Concepts (continued)
Figure 6 Reference 2 Hovercraft Concept Design Dual Propulsion/Steer motors
Propulsion Concepts (continued)
Figure 7 Reference 2 Hovercraft Concept Design Dual Propulsion motors Single lift motor
Propulsion Concepts (continued)
Figure 8 Reference 1 Hovercraft Concept Design Rear Facing Propeller with Rudders
Propulsion Concepts (continued)
Figure 9 Reference 1 Hovercraft Concept Design Air Intake and Directional Expulsion System
Propulsion Concepts (continued)
Figure 10 Hovercraft Concept Design Dual Rear Angled Propellers
Propulsion Concepts (continued)
Figure 11 Hovercraft Concept Design Dual Front Mounted Pulling Propellers
Propulsion Concepts (continued)
Figure 12 Hovercraft Concept Design Multi-Directional Propellers That Pull
A. Dual Propulsion/ Steer Motor B. Rear Mount Propulsion w/ Rear Mount Steering Fan C. Dual Mid mounted Rotating Propellers D. Dual Fixed Mid-mounted Propellers
E. (Reference) Rear Facing Propeller with rudder
F. Air Intake and Directional Expulsion System G. Dual Rear Angled Propellers H. Dual Front Mounted Pulling Propellers I. Multi Directional Propellers Photos from Reference 1
Selection Criteria
Size Minimum Fan Output Maximum Fan Output Cost Ease of Integration Weight Aesthetics Variable Power Durability # of Fans (2 is best) Turning Radius A 0 0 0 0 -' 0 0 +' 0 +' +' B -' 0 +' -' -' -' 0 +' 0 -' 0 C 0 0 +' 0 -' 0 0 +' 0 +' +' 0 +' 0 +' 0 0 +' 0 +' +' D 0 Concepts
E 0
F +'
0 0 0 0 0 0 0 0 0 0
-' -' 0 -' +' +' -' 0 -' 0 G 0 0 +' 0 +' 0 0 +' 0 +' 0 H -' 0 +' -' -' -' 0 +' -' +' -' -' I 0 +' -' -' -' -' +' -' -' +'
Sum +'s Sum 0's Sum -'s A 3 8 1 B 2 4 6 C 4 6 4 D 5 6 1
E
0 12 0 F 4 3 5 G 4 7 1 H 3 2 7 I 3 1 8 Net Score Rank Continue?
2
3
Yes -4 7 (t) No 0 4 (t) Yes 4
1
Yes 0 4 (t) Yes -1 6 No 3
2
Yes -4 7 (t) No -5 9 No
Selection Criteria
Power Requirements Size Minimum Fan Output Maximum Fan Output Cost Ease of Integration Weight Aesthetics Variable Power Durability Number of Fans Turning Radius
Weight
Dual Propulsion/ Steer Motor
Ratin g Scor e
Dual Mid mounted Rotating Propellers
Ratin g Concepts - Propulsion Scor e
Dual Fixed Mid mounted Propellers
Ratin g Scor e
(Reference) Rear Facing Propeller with rudder
Ratin g Scor e
Dual Rear Angled Propellers
Ratin g Scor e
8% 10% 5% 5% 10% 10% 10% 5% 14% 5% 8% 10%
Total Score Rank 3 3 3 3 4 2 3 3 3 3 3 4
3.1
4 0.24
0.3
0.15
0.15
0.4
0.2
0.3
0.15
0.42
0.15
0.24
0.4
2 3 3 4 3 2 3 3 4 3 4 4
3.19
3 0.16
0.3
0.15
0.2
0.3
0.2
0.3
0.15
0.56
0.15
0.32
0.4
2 3 3 4 3 4 3 3 4 3 4 3
3.44
1 0.16
0.3
0.15
0.2
0.3
0.4
0.3
0.3
0.56
0.15
0.32
0.3
3 3 3 3 3 2 3 3 2 2 2 2
2.53
5 0.24
0.3
0.15
0.15
0.3
0.2
0.3
0.15
0.28
0.1
0.16
0.2
2 3 3 4 3 3 3 3 4 3 4 3
3.34
2 0.16
0.3
0.3
0.2
0.3
0.3
0.3
0.15
0.56
0.15
0.32
0.3
Dual Fixed Mid-mounted Propellers
Power Concepts
Power Concepts
Figure 13 Reference 4 Hovercraft Power Supply Design 4 "AA" Serial Battery Holders
Power Concepts (continued)
Figure 14 Reference 5 Hovercraft Power Supply Design "PP3" Serial Battery Holders
Power Concepts (continued)
Figure 15 Reference 6 Hovercraft Power Supply Design 7.2V Rechargeable Battery Pack
Power Concepts (continued)
Figure 16 Reference 7 Hovercraft Power Supply Design Solar Panels
4 "AA" Serial Battery Holders "PP3" Serial Battery Holders (Reference) Battery Pack Solar Panels Photos from Reference 4, 5, 6, 7
Selection Criteria
Power Output Size Weight Ease of Integration Cost Availability 4 "AA" Serial Battery Holders 0 '+' '+' '+' '+' +' Sum +'s Sum 0's Sum -'s Net Score Rank Continue?
5 1 0 5 2 Yes Concepts "PP3" Serial Battery Holders (Reference) Battery Pack +' +' +' 0 0 0 Solar Panels -' 0 0 +' +' +' 0 0 0 -' -' +' 6 0 0 6 1 Yes 0 6 0 0 3 Yes 1 2 3 -2 4 No
Selection Criteria
Power Output Size Weight Ease of Integration Cost Availability
Weight
10% 20% 20% 20% 20% 10%
Total Score Rank Continue?
4 "AA" Serial Battery Holders
Rating 3 3 4 Weighted Score
0.3
0.6
0.8
Concepts - Power
"PP3" Serial Battery Holders
Rating 4 5 5 Weighted Score
0.4
1 1 (Reference) Battery Pack
Rating 2 2 3 Weighted Score
0.2
0.4
0.6
4 5 4
3.9
2 No 0.8
1 0.4
4 5 3
4.5
1 Yes 0.8
1 0.3
2 2 3
2.3
3 No 0.4
0.4
0.3
Dual Fixed Mid-mounted Propellers 4 "AA" Serial Battery Holders
Team Strider’s Gantt Chart
Hovercraft Concept Design By Team Strider
Gantt Chart
TASKS: Team Contract Prospectus Introduction, Benchmarking, and Specification Concept Generation and Selection Presentation I Preliminary Design Design Report Final Presentation and Report Research/ Specification Stage Concept Generation and Selection Stage Drawing/ Design Stage Build (Subsystems) Stage Integration Stage Prototype Testing Stage Redesign Stage WEEK 1 (Jan 30 Feb 03) WEEK 2 (Feb 6 10)
Key
Assignment Already done Presentation Project Stages: Should be done by Buffer Deadline Break WEEK 3 (Feb 13 17) WEEK 4 (Feb20 24) WEEK 5 (Feb 27 Mar 3) WEEK 6 (Mar 6 10) WEEK 7 (Mar 13 17) WEEK 8 (Mar 20 26) TASKS: Team Contract Prospectus Introduction, Benchmarking, and Specification Concept Generation and Selection Presentation I Preliminary Design Design Report Final Presentation and Report Research/ Specification Stage Concept Generation and Selection Stage Drawing/ Design Stage Build (Subsystems) Stage Integration Stage Prototype Testing Stage Redesign Stage WEEK 9 (Mar 27 31) WEEK 10 (Apr 3-7) WEEK 11(Apr 10 14) WEEK 12 (Apr17-21) WEEK 13 (Apr 24-28) WEEK 14 (May1-5) WEEK 15 (May8 11) WEEK 16 EXAMS
Conclusion
References
Reference 1: RC Hovercraft Models.
(1 March, 2006) Reference 3: Hobby Lobby www.hobby-lobby.com
(1 March, 2006) Reference 4: Thomas Distributing www.thomas-distributing.com
(5 March, 2006) RC Hovercraft Models.
References (continued)
Reference 5: Strikalite Batteries www.strikalite.co.uk
(5 March, 2006) Reference 6: Only Batteries www.onlybatteries.com
(6 March, 2006) Reference 7: Silicon Solar Inc www.siliconsolar.com
(3 March, 2006)