VEX V5 Workcell Extensions are designed to further explore concepts covered in the STEM Labs and introduce students to additional sorting and automation concepts. These extensions should be completed after going through the first twelve of the VEX V5 Workcell STEM Labs.
Each Workcell Extension begins with background information to explain the importance and contextualization of the concepts addressed in the extension, as well as information about the overall goal of the extension and what will be created. Then, guided examples are provided to reconfigure the Workcell to accomplish that Extension's goal. Note, the instructions provided can be seen as one possible solution for the purpose of inspiration, as there is more than one way to accomplish the goal. These extensions require students to plan and build new sections of the Workcell to have hands-on experience with specific engineering concepts. Three levels of challenges are available to test the construction or coding skills of students.
The Workcell Extensions can be completed in any order. However, the concepts in some extensions are more complex than others. An example, and the recommendation, of how these could be ordered is provided in the VEX V5 Workcell Pacing Guide. The table below explains concepts covered in the extensions, the importance of the concept both with the Workcell and in real-world applications, and two to three extensions that are the best example of that concept. While extensions may cover multiple concepts, only the main concept will be communicated below.
Diverters
Diverters allow for a more efficient movement of the disks from one conveyor to another, rather than using the robotic arm. This allows for disks to go on different paths in the system as the program can allow for certain disks to bypass the diverter, while others are diverted to another conveyor.
Workcell Extension(s) that Cover this Concept:
- Diverting Disks: Students will build and code a diverter to move disks from one conveyor belt to another.
- Baggage Claim: Students will create a build where multiple diverters are used to sort disks.
Gates
In some systems, disks go along different conveyor paths depending on their color. Gates minimize the number of disks going through the system at once, which can lead to a more accurate system. When using a gate or multiple gates, there is a lesser chance of disks going down the wrong path, or ending up in the wrong loading zone.
Workcell Extension(s) that Cover this Concept:
- Enable Entry: Students will create a system using only one conveyor and one gate to separate disks.
- Reject Entry: Students will use gates on either side of a disk feeder to reject red disks and accept green and blue disks.
Conveyors
Conveyors allow disks to move around a system. Rather than relying on workers to move products across a system, diverters and conveyors can be used to increase efficiency. The number and arrangement of conveyors also allows for more accurate movement of objects from one area to another.
Single and Multiple Conveyors
While every Workcell Extension uses conveyors, it is important to consider how multiple conveyors work together. Consider the speed each conveyor is moving and how the disk will transfer from one to another.
Workcell Extension(s) that Cover this Concept:
- Cost Efficiency: Students are challenged to create a system that uses the least possible materials. Being efficient with the usage of conveyors can go a long way to reduce the amount of material in the system.
Elevated and Overlapping Conveyors
Rather than expanding a system out across the floor, companies can raise parts of their system to optimize their current space. If the factory is a multi-level system, the items can be introduced to the system from a higher level rather than having a group of people bringing the items down to the floor level to be introduced to the system.
Workcell Extension(s) that Cover this Concept:
- Going Higher: Students will build an elevated conveyor to move disks between different heights of conveyors.
- Fast Factory: Students will create projects to move disks from lower conveyors to elevated conveyors related to the end destination.
- Leveling Up: Students create overlapping conveyors on the system to move disks.
Turning Conveyors
Rotating conveyor belts allows disks to flow onto another conveyor without the use of a diverter or the robotic arm. This can be a more efficient option if there are multiple outputs.
Workcell Extension(s) that Cover this Concept:
- Turning It Up: Students will construct a conveyor belt that turns to sort disks.
- New Heights: Students will construct a system that uses multiple overlapping conveyors and a turning conveyor to complete challenges.
Sensors
Sensors can increase the accuracy and efficiency of a system. The sensors can report the location of an object along a conveyor, the color of the object, or be used to determine the turning radius of diverters. This added functionality allows you to begin automating systems rather than relying on manual inputs to report the presence or color of an object.
Line Trackers
Line Trackers report the percentage of light being reflected back from the sensor. This allows you to code the Workcell to respond when objects are detected at a certain position on a conveyor. This is also covered in Lab 10. For more information on using line trackers, view this article from the VEX Library.
Workcell Extension(s) that Cover this Concept:
- Sort the Luggage: Students will build a system to sort disks into the correct area to act as luggage. They are encouraged to use sensors, like Line Trackers, to determine the position of the disks along the conveyors.
Optical Sensors
Optical Sensors can be used to detect color, proximity, and ambient light. This allows for a project to include different behaviors depending on the color reported by the sensor. For more information on using optical sensors, view this article from the VEX Library.
Workcell Extension(s) that Cover this Concept:
- Baggage Claim: Students will program a User Interface (UI) and Optical Sensor(s) to pick up the disks from their loading zone and sort them on a conveyor system.
Limit Switches
Limit Switches can be used to distinguish the turning radius of a diverter and a gate. This sensor can also replace a time sensor when having disks move from one conveyor to another without a diverter or a Line Tracker to stop a conveyor. For more information on using limit switches, view this article from the VEX Library.
Workcell Extension(s) that Cover this Concept:
- Quality Control: Students will use Limit Switches to reject red disks when they enter the system.
Altered Disk Feeder
The extended disk feeder allows for more disks to be autonomously introduced into a system at a time. With the original disk feeder, only four disks could be held at a time.
Workcell Extension(s) that Cover this Concept:
- Fast Factory: Students will create projects to move disks from lower conveyors to elevated conveyors related to the end destination. Levels 2 and 3 require up to 12 disks to be completed, so using an altered disk feeder is necessary to hold all disks.
- Stay on Track: Students will create a retaining wall and other modifications to increase efficiency sorting disks. The altered disk feeder is used in Level 3 of the challenge to test the efficiency of sorting 12 disks.
Retaining Wall
Sometimes when disks are transitioning from one conveyor to another, they fall off the second conveyor due to the speed they are moving. This is also seen when going around bends in circular conveyors. Rather than decreasing the velocity of the conveyor, retaining walls can be built to keep the disk on the conveyor.
Workcell Extension(s) that Cover this Concept:
- Stay on Track: Students will create a retaining wall and other modifications to increase efficiency sorting disks.
User Interface
A User Interface (or UI) is a method to allow a user to interact with a computer system (or machine) to provide input or observe outputs. UI's are helpful when you want to trigger different behaviors of the Workcell depending on the button pressed by a human. This manual input is helpful when testing behaviors. This is also covered in Lab 7.
Workcell Extension(s) that Cover this Concept:
- Baggage Claim: Students will program a UI and Optical Sensor(s) to pick up the disks from their loading zone and sort them on a conveyor system.
Multiple Workcells
Some companies have multiple sections working together rather than having one section in charge of every part. This is illustrated through Workcells with disks being moved with the first robotic arm, being separated on different conveyors, then actually being placed into the correct loading zones using the second robotic arm.
Workcell Extension(s) that Cover this Concept:
- Work Together: Students will work together to use two Workcells in order to sort disks by color and place them in a certain color order within a disk feeder.