The document describes several dual gear train concepts for lifting a mass: 1. A dual gear train uses two separate but equal gear trains operating in parallel to equally distribute torque on the end axle and reduce stress. 2. A two-speed gearbox lifts the mass faster by using a slower gear for initial lifting and a faster gear for accelerated lifting. 3. A compound planetary gearbox provides compact, modular gear reduction through multiple planetary gears, each multiplying torque exponentially to achieve high reduction.

2. Dual Gear Train
Parallel gear trains To prevent moments
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1 Two separate but equal gear trains operate parallel to each
other to allow equal distribution of torque on the end axle.
This can also reduce potential stress within the axle.
If the mass is directly underneath the center of mass / gravity,
then it prevents moments from being created.
If gear trains can act independently, then the mass and
torque can be split to increase overall speed it is lifted

3. Dual Gear Train
Pros:
- Equal spread of forces
- Linear design means cancellation of forces
- Mass hanging under center of gravity / mass
Cons:
- Gearbox length
- Maximum axial length of the gearbox is a cubed
denominator
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Parallel gear trains To prevent moments

4. Two speed gearbox
Mass is lifted faster after momentum is made
After the mass has been lifted and is accelerating, the second gear
with faster speed will start to slowly take over the control of the axle,
bringing it up faster.
If at any point the faster gear is unable to take it, the axle will be
pushed along by the slower gear with higher torque.
This would require a system where two different speed gears are able
to automatically take control over a single axle by itself.
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5. Two Speed Gearbox
Mass is lifted faster after momentum is made
Pros:
- Reduces the time taken to lift the mass.
- Could lift a heavier mass in the same time as a light mass in a different gearbox
- Automatically shifts based on the physical interactions within the gearbox
Cons:
- Very difficult to produce
- Time gained may be miniscule
- Would work better in a horizontal plane compared to a Vertical plane.
- Gears may get stuck, faster gears may break
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6. Compound Planetary
Compact and Modular Gear Reduction
Size: 70mm dia. X 9mm width (subject to change)
Each planetary gear multiplies the torque by a small amount while
also reducing the axial length.
Each subsequent compound planetary multiplies it exponentially
until it reaches required torque to lift mass.
Example shown has a 3 gear teeth sizes: 15, 30, 75
If you have 1 planetary gear; 5:1
2 planetary gears; 25:1
3 planetary gears; 125:1
Optimal size could be found if best mass and time values are known
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Driving
Pinion

7. Compound Planetary
Compact and Modular Gear Reduction
Pros:
- Compact Size
- Distributed Forces
- Reduced Wear
- Symmetrical and Aesthetically Pleasing
- Modular and Modifiable
Cons:
- Tolerance of Parts has to be very accurate
- If one component gets caught, it is hard to fix
- Central Driving gear is smaller compared to Planets
- Increased complexity which may cause problems
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8. Spiral Compound
Reducing size by changing direction of gears
To reduce size of the gearbox, the gears are not placed in
a linear fashion.
If gears are placed in one plane of motion, then the forces
acting on the system will be acting in controlled directions.
Gears could spiral around the bolt fixture.
String could wrap around the bolt or the axles to reduce
effort needed to pick something up.
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9. Spiral Compound
Reducing size by changing direction of gears
Pros:
- Compact Space
- Mass is lined up vertically with the bolt
- Symmetrical design
Cons:
- Only a few specific gear ratios would work to fit the Bolt in the centre
- Would have to have at least 3 - 6 gears
- The Gearbox may swivel around the bolt
- The bolt thread may damage the gearbox.
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10. SHared Axle System
compact compound linear system
The shared axle system requires only two axles
which have series of compound gears. The sets of
compound gears interact with each other but are not
fixed to the axles.
Only the final gear on the system is fixed to the axle
so that the axle rotates at the required speed.
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11. SHared Axle System
compact compound linear system
Pros:
- Compact
- Simple design to produce
- Linear design
Cons:
- Possible increase in friction
- Creating mounting point where the system is
balanced
- Gears may need spacing to reduce Friction between
gear faces
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12. CHOSEN CONCEPT
Shared axle System
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11 Adjustments we may make:
- Move the string around
- Change Gear Ratio
- Change number of gears
- Move Motor
- Change how string is
attached
- Creating better spacing
between gears
- Create supports for axles