gears & vex. agenda essential terminology gear types gearing up/gearing down direction gear...
TRANSCRIPT
![Page 1: Gears & VEX. Agenda Essential Terminology Gear Types Gearing Up/Gearing Down Direction Gear Ratios Example Application: Sumo-Bot Competition gear testing](https://reader038.vdocuments.site/reader038/viewer/2022102801/56649e4c5503460f94b4223a/html5/thumbnails/1.jpg)
Gears & VEX
![Page 2: Gears & VEX. Agenda Essential Terminology Gear Types Gearing Up/Gearing Down Direction Gear Ratios Example Application: Sumo-Bot Competition gear testing](https://reader038.vdocuments.site/reader038/viewer/2022102801/56649e4c5503460f94b4223a/html5/thumbnails/2.jpg)
Agenda
• Essential Terminology• Gear Types• Gearing Up/Gearing Down• Direction• Gear Ratios• Example• Application: Sumo-Bot Competition
gear testing apparatus
![Page 3: Gears & VEX. Agenda Essential Terminology Gear Types Gearing Up/Gearing Down Direction Gear Ratios Example Application: Sumo-Bot Competition gear testing](https://reader038.vdocuments.site/reader038/viewer/2022102801/56649e4c5503460f94b4223a/html5/thumbnails/3.jpg)
Essential Terminology
• Driver – gear attached to a motor• Follower – gear doing useful work• Idler – gear between the driver and follower• Gear Train – a row of gears• Geared Up – the follower moves faster than the
driver• Geared Down – the follower moves slower than the
driver• Compound gears – a gear train with multiple gears
on one axle
![Page 4: Gears & VEX. Agenda Essential Terminology Gear Types Gearing Up/Gearing Down Direction Gear Ratios Example Application: Sumo-Bot Competition gear testing](https://reader038.vdocuments.site/reader038/viewer/2022102801/56649e4c5503460f94b4223a/html5/thumbnails/4.jpg)
Do you get it?
• Which gear is the driver (A or B)?
• Which gear is the follower (A or B)?
A B
motor
![Page 5: Gears & VEX. Agenda Essential Terminology Gear Types Gearing Up/Gearing Down Direction Gear Ratios Example Application: Sumo-Bot Competition gear testing](https://reader038.vdocuments.site/reader038/viewer/2022102801/56649e4c5503460f94b4223a/html5/thumbnails/5.jpg)
Do you get it?
• Which gear is the driver (A or B)? → A
• Which gear is the follower (A or B)? → B
A B
motor
![Page 6: Gears & VEX. Agenda Essential Terminology Gear Types Gearing Up/Gearing Down Direction Gear Ratios Example Application: Sumo-Bot Competition gear testing](https://reader038.vdocuments.site/reader038/viewer/2022102801/56649e4c5503460f94b4223a/html5/thumbnails/6.jpg)
Do you get it?
• Which gear is the follower (A, B, or C)?• Which gear is the driver (A, B, or C)? • Which gear is the idler (A, B, or C)?
A B C
motorwheel
![Page 7: Gears & VEX. Agenda Essential Terminology Gear Types Gearing Up/Gearing Down Direction Gear Ratios Example Application: Sumo-Bot Competition gear testing](https://reader038.vdocuments.site/reader038/viewer/2022102801/56649e4c5503460f94b4223a/html5/thumbnails/7.jpg)
Do you get it?
• Which gear is the follower (A, B, or C)? → C• Which gear is the driver (A, B, or C)? → A• Which gear is the idler (A, B, or C)? → B
A B C
motorwheel
![Page 8: Gears & VEX. Agenda Essential Terminology Gear Types Gearing Up/Gearing Down Direction Gear Ratios Example Application: Sumo-Bot Competition gear testing](https://reader038.vdocuments.site/reader038/viewer/2022102801/56649e4c5503460f94b4223a/html5/thumbnails/8.jpg)
Gear Types
spur gears
differential bevel gears rack & pinion worm gear
![Page 9: Gears & VEX. Agenda Essential Terminology Gear Types Gearing Up/Gearing Down Direction Gear Ratios Example Application: Sumo-Bot Competition gear testing](https://reader038.vdocuments.site/reader038/viewer/2022102801/56649e4c5503460f94b4223a/html5/thumbnails/9.jpg)
Spur Gears
84 tooth
60 tooth
36 tooth
24 tooth
12 tooth
![Page 10: Gears & VEX. Agenda Essential Terminology Gear Types Gearing Up/Gearing Down Direction Gear Ratios Example Application: Sumo-Bot Competition gear testing](https://reader038.vdocuments.site/reader038/viewer/2022102801/56649e4c5503460f94b4223a/html5/thumbnails/10.jpg)
Worm Gears
worm gear
Worm gears allow axles at right angles to transfer
rotational motion.
![Page 11: Gears & VEX. Agenda Essential Terminology Gear Types Gearing Up/Gearing Down Direction Gear Ratios Example Application: Sumo-Bot Competition gear testing](https://reader038.vdocuments.site/reader038/viewer/2022102801/56649e4c5503460f94b4223a/html5/thumbnails/11.jpg)
Bevel Gears
Bevel gears allow rotational motion to
be transferred at right angles.
![Page 12: Gears & VEX. Agenda Essential Terminology Gear Types Gearing Up/Gearing Down Direction Gear Ratios Example Application: Sumo-Bot Competition gear testing](https://reader038.vdocuments.site/reader038/viewer/2022102801/56649e4c5503460f94b4223a/html5/thumbnails/12.jpg)
Rack & Pinion
rack
pinion
Racks and pinions are used to translate rotational motion into linear motion.
![Page 13: Gears & VEX. Agenda Essential Terminology Gear Types Gearing Up/Gearing Down Direction Gear Ratios Example Application: Sumo-Bot Competition gear testing](https://reader038.vdocuments.site/reader038/viewer/2022102801/56649e4c5503460f94b4223a/html5/thumbnails/13.jpg)
Differential
Differentials are devices that allow each of the axles to rotate at different speeds, while supplying equal torque to each of them.
![Page 14: Gears & VEX. Agenda Essential Terminology Gear Types Gearing Up/Gearing Down Direction Gear Ratios Example Application: Sumo-Bot Competition gear testing](https://reader038.vdocuments.site/reader038/viewer/2022102801/56649e4c5503460f94b4223a/html5/thumbnails/14.jpg)
Sprockets & Chains
Sprockets inside the same chain rotate in the same direction.
Sprockets outside the chain rotate in the opposite direction.
![Page 15: Gears & VEX. Agenda Essential Terminology Gear Types Gearing Up/Gearing Down Direction Gear Ratios Example Application: Sumo-Bot Competition gear testing](https://reader038.vdocuments.site/reader038/viewer/2022102801/56649e4c5503460f94b4223a/html5/thumbnails/15.jpg)
Pulleys & Belts
Pulleys and belts are not available for VEX
Sometimes tank treads can be used as belts.
![Page 16: Gears & VEX. Agenda Essential Terminology Gear Types Gearing Up/Gearing Down Direction Gear Ratios Example Application: Sumo-Bot Competition gear testing](https://reader038.vdocuments.site/reader038/viewer/2022102801/56649e4c5503460f94b4223a/html5/thumbnails/16.jpg)
Direction
• even number of gears:
driver & follower turn in
opposite directions
• odd number of gears:
driver & follower turn in
same direction
driver
driver
driver
follower
follower
follower
![Page 17: Gears & VEX. Agenda Essential Terminology Gear Types Gearing Up/Gearing Down Direction Gear Ratios Example Application: Sumo-Bot Competition gear testing](https://reader038.vdocuments.site/reader038/viewer/2022102801/56649e4c5503460f94b4223a/html5/thumbnails/17.jpg)
Did you get it?
driver
Would the follower gear move clockwise or counterclockwise?
![Page 18: Gears & VEX. Agenda Essential Terminology Gear Types Gearing Up/Gearing Down Direction Gear Ratios Example Application: Sumo-Bot Competition gear testing](https://reader038.vdocuments.site/reader038/viewer/2022102801/56649e4c5503460f94b4223a/html5/thumbnails/18.jpg)
Did you get it?
driver
Would the follower gear move clockwise or counterclockwise?
![Page 19: Gears & VEX. Agenda Essential Terminology Gear Types Gearing Up/Gearing Down Direction Gear Ratios Example Application: Sumo-Bot Competition gear testing](https://reader038.vdocuments.site/reader038/viewer/2022102801/56649e4c5503460f94b4223a/html5/thumbnails/19.jpg)
Did you get it?
driver
Would the follower gear move clockwise or counterclockwise?
![Page 20: Gears & VEX. Agenda Essential Terminology Gear Types Gearing Up/Gearing Down Direction Gear Ratios Example Application: Sumo-Bot Competition gear testing](https://reader038.vdocuments.site/reader038/viewer/2022102801/56649e4c5503460f94b4223a/html5/thumbnails/20.jpg)
Did you get it?
driver
Would the follower gear move clockwise or counterclockwise?
![Page 21: Gears & VEX. Agenda Essential Terminology Gear Types Gearing Up/Gearing Down Direction Gear Ratios Example Application: Sumo-Bot Competition gear testing](https://reader038.vdocuments.site/reader038/viewer/2022102801/56649e4c5503460f94b4223a/html5/thumbnails/21.jpg)
Geared Up
• large driver turns small follower
• increases speed• decreases torque
(turning force)
driven gear follower geardriver
follower
![Page 22: Gears & VEX. Agenda Essential Terminology Gear Types Gearing Up/Gearing Down Direction Gear Ratios Example Application: Sumo-Bot Competition gear testing](https://reader038.vdocuments.site/reader038/viewer/2022102801/56649e4c5503460f94b4223a/html5/thumbnails/22.jpg)
Geared Down
• small driver turns large follower
• increases torque (turning force)
• decreases speed
driven gear follower gear
follower
driver
![Page 23: Gears & VEX. Agenda Essential Terminology Gear Types Gearing Up/Gearing Down Direction Gear Ratios Example Application: Sumo-Bot Competition gear testing](https://reader038.vdocuments.site/reader038/viewer/2022102801/56649e4c5503460f94b4223a/html5/thumbnails/23.jpg)
Gear Analysis
To analyze any gear train you need to:
1. Locate the driver gear
2. Locate the follower gear
3. Calculate the Gear Ratio
Use the following rules to calculate gear ratios.
![Page 24: Gears & VEX. Agenda Essential Terminology Gear Types Gearing Up/Gearing Down Direction Gear Ratios Example Application: Sumo-Bot Competition gear testing](https://reader038.vdocuments.site/reader038/viewer/2022102801/56649e4c5503460f94b4223a/html5/thumbnails/24.jpg)
Gear Ratios(determining what a gear will do)
Example Gear Ratio:– ⅓ or 1:3 – read as 1 to 3– 1 turn of the driver will turn the follower 3 times
thdriver tee
eethfollower t ratiogear
![Page 25: Gears & VEX. Agenda Essential Terminology Gear Types Gearing Up/Gearing Down Direction Gear Ratios Example Application: Sumo-Bot Competition gear testing](https://reader038.vdocuments.site/reader038/viewer/2022102801/56649e4c5503460f94b4223a/html5/thumbnails/25.jpg)
What is the gear ratio?
84 tooth driver
60 tooth follower
![Page 26: Gears & VEX. Agenda Essential Terminology Gear Types Gearing Up/Gearing Down Direction Gear Ratios Example Application: Sumo-Bot Competition gear testing](https://reader038.vdocuments.site/reader038/viewer/2022102801/56649e4c5503460f94b4223a/html5/thumbnails/26.jpg)
What is the gear ratio?
driver
follower
7
5
teeth84
teeth60
thdriver tee
eethfollower t ratiogear
![Page 27: Gears & VEX. Agenda Essential Terminology Gear Types Gearing Up/Gearing Down Direction Gear Ratios Example Application: Sumo-Bot Competition gear testing](https://reader038.vdocuments.site/reader038/viewer/2022102801/56649e4c5503460f94b4223a/html5/thumbnails/27.jpg)
Long Gear Trains
The gear attached to the motor is the driver.
The gear doing work is the follower.
All in-between gears are idlers.
Ignore the idler gears!
DriverIdlers
Follower Gear Ratio = 24/40
= 3/5
3 turns of the 40 tooth gear will turn the 24 tooth gear 5 times.
![Page 28: Gears & VEX. Agenda Essential Terminology Gear Types Gearing Up/Gearing Down Direction Gear Ratios Example Application: Sumo-Bot Competition gear testing](https://reader038.vdocuments.site/reader038/viewer/2022102801/56649e4c5503460f94b4223a/html5/thumbnails/28.jpg)
Compound Gears(Multiple Gears on One Axle)
1. Pair up drivers and followers
2. Start a new driver/follower pair if an axle has a second gear attached.
3. Multiply the gear ratios of all the driver/follower pairs.
D2
Gear 1 = 12 teeth Gear 2 = 36 teeth
Gear 3 = 12 teeth Gear 4 = 60 teeth
![Page 29: Gears & VEX. Agenda Essential Terminology Gear Types Gearing Up/Gearing Down Direction Gear Ratios Example Application: Sumo-Bot Competition gear testing](https://reader038.vdocuments.site/reader038/viewer/2022102801/56649e4c5503460f94b4223a/html5/thumbnails/29.jpg)
Compound Gears(Multiple Gears on One Axle)
1. Pair up drivers and followers
2. Start a new driver/follower pair if an axle has a second gear attached.
3. Multiply the gear ratios of all the driver/follower pairs.
D2
Gear 1 = 12 teeth Gear 2 = 36 teeth
Gear 3 = 12 teeth Gear 4 = 60 teeth
Gear 1 & Gear 2:
1
3
12
36
driver
follower
![Page 30: Gears & VEX. Agenda Essential Terminology Gear Types Gearing Up/Gearing Down Direction Gear Ratios Example Application: Sumo-Bot Competition gear testing](https://reader038.vdocuments.site/reader038/viewer/2022102801/56649e4c5503460f94b4223a/html5/thumbnails/30.jpg)
Compound Gears(Multiple Gears on One Axle)
1. Pair up drivers and followers
2. Start a new driver/follower pair if an axle has a second gear attached.
3. Multiply the gear ratios of all the driver/follower pairs.
1
15
1
5x
1
3
D2
Gear 1 = 12 teeth Gear 2 = 36 teeth
Gear 3 = 12 teeth Gear 4 = 60 teeth
Gear 1 & Gear 2:
Gear 3 & Gear 4:
1
3
12
36
driver
follower
1
5
12
60
driver
follower
Multiply the gear ratios:
![Page 31: Gears & VEX. Agenda Essential Terminology Gear Types Gearing Up/Gearing Down Direction Gear Ratios Example Application: Sumo-Bot Competition gear testing](https://reader038.vdocuments.site/reader038/viewer/2022102801/56649e4c5503460f94b4223a/html5/thumbnails/31.jpg)
Compound Gears(Multiple Gears on One Axle)
1. Pair up drivers and followers
2. Start a new driver/follower pair if an axle has a second gear attached.
3. Multiply the gear ratios of all the driver/follower pairs.
1
15
1
5
1
3
D2
Gear 1 = 12 teeth Gear 2 = 36 teeth
Gear 3 = 12 teeth Gear 4 = 60 teeth
Gear 1 & Gear 2:
Gear 3 & Gear 4:
1
3
12
36
driver
follower
1
5
12
60
driver
follower
Multiply the gear ratios:
15:1
![Page 32: Gears & VEX. Agenda Essential Terminology Gear Types Gearing Up/Gearing Down Direction Gear Ratios Example Application: Sumo-Bot Competition gear testing](https://reader038.vdocuments.site/reader038/viewer/2022102801/56649e4c5503460f94b4223a/html5/thumbnails/32.jpg)
Calculate the Gear Ratio(Assume the last axle does the useful work)
36t
36t
60t
12t
12t
1 23
4
12t
![Page 33: Gears & VEX. Agenda Essential Terminology Gear Types Gearing Up/Gearing Down Direction Gear Ratios Example Application: Sumo-Bot Competition gear testing](https://reader038.vdocuments.site/reader038/viewer/2022102801/56649e4c5503460f94b4223a/html5/thumbnails/33.jpg)
Calculate the Gear Ratio(Assume the last axle does the useful work)
36t
36t
60t
12t
12t
1 23
4
Pair 1:
1
3
12
36
driver
follower
12t
![Page 34: Gears & VEX. Agenda Essential Terminology Gear Types Gearing Up/Gearing Down Direction Gear Ratios Example Application: Sumo-Bot Competition gear testing](https://reader038.vdocuments.site/reader038/viewer/2022102801/56649e4c5503460f94b4223a/html5/thumbnails/34.jpg)
Calculate the Gear Ratio(Assume the last axle does the useful work)
36t
36t
60t
12t
12t
1 23
4
Pair 1:
1
3
12
36
driver
follower
1
3
12
36
driver
follower
Pair 2:
12t
![Page 35: Gears & VEX. Agenda Essential Terminology Gear Types Gearing Up/Gearing Down Direction Gear Ratios Example Application: Sumo-Bot Competition gear testing](https://reader038.vdocuments.site/reader038/viewer/2022102801/56649e4c5503460f94b4223a/html5/thumbnails/35.jpg)
Calculate the Gear Ratio(Assume the last axle does the useful work)
36t
36t
60t
12t
12t
1 23
4
Pair 1:
Pair 3:
1
3
12
36
driver
follower
1
5
12
60
driver
follower
1
3
12
36
driver
follower
Pair 2:
12t
![Page 36: Gears & VEX. Agenda Essential Terminology Gear Types Gearing Up/Gearing Down Direction Gear Ratios Example Application: Sumo-Bot Competition gear testing](https://reader038.vdocuments.site/reader038/viewer/2022102801/56649e4c5503460f94b4223a/html5/thumbnails/36.jpg)
Calculate the Gear Ratio(Assume the last axle does the useful work)
36t
36t
60t
12t
12t
1 23
4
1
45
1
5
1
3
1
3
Pair 1:
Pair 3:
1
3
12
36
driver
follower
1
5
12
60
driver
follower
Multiply the gear ratios:
1
3
12
36
driver
follower
Pair 2:
45:1
12t
![Page 37: Gears & VEX. Agenda Essential Terminology Gear Types Gearing Up/Gearing Down Direction Gear Ratios Example Application: Sumo-Bot Competition gear testing](https://reader038.vdocuments.site/reader038/viewer/2022102801/56649e4c5503460f94b4223a/html5/thumbnails/37.jpg)
Team Unlimited’s2-Speed Transmission
![Page 38: Gears & VEX. Agenda Essential Terminology Gear Types Gearing Up/Gearing Down Direction Gear Ratios Example Application: Sumo-Bot Competition gear testing](https://reader038.vdocuments.site/reader038/viewer/2022102801/56649e4c5503460f94b4223a/html5/thumbnails/38.jpg)
Calculate This:
Is this transmission currently geared up or down? → geared down
What is the current gear ratio of this transmission? → 60:36 = 5:3
What is the gear ratio of the other set of gears? → 60:60 = 1:1
60 tooth 36 tooth 60 tooth
36 tooth 60 tooth 60 tooth
![Page 39: Gears & VEX. Agenda Essential Terminology Gear Types Gearing Up/Gearing Down Direction Gear Ratios Example Application: Sumo-Bot Competition gear testing](https://reader038.vdocuments.site/reader038/viewer/2022102801/56649e4c5503460f94b4223a/html5/thumbnails/39.jpg)
Calculate This:
Is this transmission currently geared up or down? → geared down
What is the current gear ratio of this transmission? → 60:36 = 5:3
What is the gear ratio of the other set of gears? → 60:60 = 1:1
60 tooth 36 tooth 60 tooth
36 tooth 60 tooth 60 tooth
![Page 40: Gears & VEX. Agenda Essential Terminology Gear Types Gearing Up/Gearing Down Direction Gear Ratios Example Application: Sumo-Bot Competition gear testing](https://reader038.vdocuments.site/reader038/viewer/2022102801/56649e4c5503460f94b4223a/html5/thumbnails/40.jpg)
Sumo-Bot• All robots are placed in a
10’ x 10’ field
• If any part of a robot touches the field wall, it is removed
• The last robot left on the field wins!
![Page 41: Gears & VEX. Agenda Essential Terminology Gear Types Gearing Up/Gearing Down Direction Gear Ratios Example Application: Sumo-Bot Competition gear testing](https://reader038.vdocuments.site/reader038/viewer/2022102801/56649e4c5503460f94b4223a/html5/thumbnails/41.jpg)
Good Luck!
Hint: use gears to get the perfect combination of speed & torque
![Page 42: Gears & VEX. Agenda Essential Terminology Gear Types Gearing Up/Gearing Down Direction Gear Ratios Example Application: Sumo-Bot Competition gear testing](https://reader038.vdocuments.site/reader038/viewer/2022102801/56649e4c5503460f94b4223a/html5/thumbnails/42.jpg)
Thanks/Resources
• Teaching Gear Theory to Students
• CMU's Vex Curriculum: Gearbox Lesson