The VEX GO build system is a fun and easy way to allow students in grades three to five to explore the principles of motion. Its flexibility and function can also be used in higher grades.
This article will introduce you to parts which will allow your VEX GO projects to move.
These parts include:
As you build projects with these parts there is a key idea to keep in mind. It takes a force to move a distance. A larger wheel, a larger gear, or a larger pulley will travel a longer distance every time they make one complete turn, but this will require more force. A smaller wheel, a smaller gear, or a smaller pulley will travel a shorter distance, but this will require less force.
The VEX GO system has three types of wheels.
- The Blue Wheel.
- The Gray Wheel.
- The Tire.
The Blue Wheel has eight attachment holes to attach other parts to the wheel and it has a center round hole which will allow the wheel to spin freely on a pin or shaft.
The Gray Wheel has eight attachment holes to attach other parts to the wheel and it has a square center hole. The square hole will allow a square pin/shaft to be inserted and allow for a power transfer to force the wheel to spin.
The Tire can be combined with a Green Pulley to create a small wheel. The Green Pulley has a square center hole that will allow a square pin/shaft to be inserted and allow for a power transfer to force the pulley to spin.
The Code Base project provides a very good example of how the wheels work. The center round hole of the project’s Blue Wheels allows the wheels to freely roll. The center square holes of the Gray Wheels allows the motors to transfer their power to the shafts which will force the Code Base to move.
Gears are very useful parts. Gears can be used to transfer power from one to another. Gears can be combined to “gear up” an assembly and this will make the assembly move faster, but it will not be able to exert as much force. Gears can be combined to “gear down” an assembly and this will make the assembly move slower, but it will be able to exert more force.
To determine how a gear system will “gear up” or “gear down'', it is important to know the number of teeth on a gear. You can find this out by picking one tooth on a gear and then counting the teeth around the gear back to that tooth.
The VEX GO system has four different gears. Three of these gears have a square center hole that will allow a square pin/shaft to be inserted and allow for a power transfer to force the gear/shaft to spin.
The gears in the VEX GO system include:
- The Red Gear.
- The Green Gear.
- The Blue Gear.
- The Pink Gear.
The Red Gear has eight teeth and a center square hole.
The Green Gear has 16 teeth and a center square hole.
The Blue Gear has 24 teeth. It has four attachment holes to attach other parts to the gear and a square center hole.
The Pink Gear has 24 teeth and four attachment holes. Its center hole is round and will allow the gear to spin freely on a shaft or pin.
Some important ideas to understand about gears are:
- Power transfer.
- Spin direction.
- Gearing up.
- Gearing down.
Power transfer can occur between two assembled gears. The gear which has power applied to it (known as the driving gear) will transfer its power to the next gear (known as the driven gear).
When two gears are assembled, the driven gear will spin in the opposite direction as the driving gear wheel is spinning. For example, if the driving gear is spinning in a clockwise direction, the driven gear will spin counterclockwise.
Gearing up occurs when two gears are assembled and the driving gear has more teeth than the driven gear. For example, what if the driving gear has 24 teeth (Blue Gear) and the driven gear has eight teeth (Red Gear)?
When the driving gear spins its 24 teeth around once, it will force the driven gear with eight teeth to be turned three complete times. The driven gear will spin three times faster; however, the gear will only be able to apply 1/3 the force.
Gearing down occurs when the driving gear has fewer teeth than the driven gear. For example, what would happen if the driving gear has eight teeth (Red Gear) and the driven gear has 24 teeth (Blue Gear)?
When the driving gear’s eight teeth have made one complete turn, the 24-tooth driven gear will have only turned 1/3 of a turn (eight teeth). The driven gear will be spinning at 1/3 the speed; however, it will be able to apply three times the force.
The Supercar build includes some very good examples of how gears can be used.
The force to move the car starts from the energy of a stretched rubber band. The attachment holes on a Blue Gear allows a Red Square Beam to be attached with standoffs to help the rubber band move the Blue Gear.
A second Blue Gear provides a power transfer.
A gearing up occurs when the second Blue Gear drives the Red Gear on the shaft of the Gray Wheel making the Supercar move!
Pulleys are very versatile parts. Some of the things they can be used for include:
- Pulley Systems.
The VEX GO system has two sizes of pulleys. Both of the pulleys have a square center hole that allows a square pin/shaft to be inserted and allow for a power transfer to force the pulley to spin. The pulleys include:
- The smaller Green Pulley which has been mentioned earlier in this article and can be combined with the Tire to create a small wheel.
- The larger Orange Pulley which has four round attachment holes in order to attach other parts to the pulley.
The Pulleys in the VEX GO system can be combined with the Ropes to create a pulley system. A pulley system can either change the direction of a force applied to a rope or increase its mechanical advantage.
Pulleys, gears, and wheels are fun parts. Use your imagination to create eyes, heads, or any other things for your projects.
Wheels, gears, and pulleys are important parts for your VEX GO system. They will bring motion to your projects. Motion will bring your imagination into reality!