done by Inhwan Kong, Leon Qin, Muhamad Redhuan and Darren Chong

1. MACHINE DESIGN

2. OUR GOALS
• to lift a weight of 10kg up a ramp
• move the weight at least 500mm along the ramp
• Performance :
• P =
𝑚𝑔ℎ
𝑉𝐼𝑇
𝑚𝑔ℎ
𝑡𝐷3

3. GEAR BOX DESIGN: SPUR GEARS

4. CALCULATION

5. CALCULATION

6. CALCULATION

7. DECISION PROCESS
• spur gear was chosen over alternatives due to various reasons.
• The calculations required for alternatives were much more difficult.
• Decision had to be made on difficulty vs viability

8. BRAINSTORMING (DOUBLE REVERSE)
• Double reverse was used to find problems from our design
• we identified problems with our very brief sketch and looked for ways of making
those problems worse to turn the ideas around
• Problems we identified were:
• -planned gear sizes were too big
• -gear ratio was too small and was not producing enough torque

9. SOLUTIONS
• Making each gear sizes smaller but also increase the number of gears
• For the second problem, we decided to increase the overall number of gears
driven with double reduction train rather than increasing gear ratio of individual
pinion and gear pairs

10. CONTACT RATIO OF DESIGN
• Low noise behaviour in gear units is an important selection criteria
• In several gear tests and practical researches, the gear contact ratio has been
reported with a large effect on noise level
• Gear design with a high contact ratio is an important key for reducing noise levels
• The group calculated a contact ratio of approx 3 for our design (this may be
inaccurate due to draft design)