Selecting a VEX IQ Assembly

Each year at the VEX Robotics World Championship the VEX IQ Challenge game for the next year is released. In addition to this, in classrooms all over the world hundreds of creative games are developed every day. These games have unique game pieces of different shapes, sizes, weights, and purposes. In order to play with these game pieces robot designs need to have specialized assemblies.

Effective and efficient assemblies will give a robot a competitive advantage. Game strategy analysis should be the starting point when deciding on a design. That means asking, "How is the robot going to play the game?"

Some other factors to consider when deciding on a type assembly include:

• Are there any specific game rules related to the handling of game pieces or for the robot design?
• Consider the level of experience and knowledge. Does it match the complexity of the design?
• Assessing the amount of time available to assemble the design, is there enough time for completion? 

For example, in the 2019-2020 VEX IQ Challenge, Squared Away, a plow could be quickly and easily be attached to a drivetrain which allows the robot to push the Cube game pieces into the Scoring Zones. Whereas, assembling linear lifts on both sides of a robot in order to carry two cubes at a time and place them on the Platforms, along with a roller claw to pick up and score the balls, would require much more planning and time to assemble.

One of the advantages of the VEX plastic construction system is it allows for many designs and a nearly endless opportunity for creativity. This allows for a wide variety of different types of assemblies and most likely new designs which have yet to be assembled. In order to provide a starting point, here are some descriptions of different assemblies which can be used to play a game.

Passive Assemblies

Passive Assemblies use no motors. The rules of many robotics games limit the number of motors a robot can possess. Designing a passive assembly allows the robot’s motors to be used for additional functions. Passive Assemblies are moved by being attached to a drivetrain or other motor-driven assembly. They can also contain stored energy from Rubber Bands. Passive Assemblies can be some of the easiest and quickest types of designs to assemble, although they can be very complex with manual releases and re-set mechanisms. Some examples of passive manipulators which can be used to play a robotics game include:

• Plows are usually attached to the drivetrain and typically their functions are pushing game pieces around and/or keeping the robot from driving up on game pieces and becoming immobile.
• Forks and hooks (types of passive claws) are typically attached to an arm and are usually designed to slide under game pieces in order to pick them up or hook onto a bar so a robot can lift itself. 
• Shields are designed to keep game pieces from falling into the robot. 
• Game piece slides are designed to allow game pieces to slide out of the slide and into the goal or scoring zone.

Motor-Driven Assemblies

Motor-driven assemblies can have a motor spin an assembly directly attached to a shaft or be assembled in combination with a gear train, chain and sprocket system, or other parts available in the Motion Product line. Typically, motor-driven assemblies take more time and planning to put together than passive assemblies. Some examples which can be used in a robotics game include:

• Arms are usually attached to a tower on the robot chassis and are used to lift another assembly on the end of the arm or to lift the robot off the ground.
• Claws are usually attached to an end of an arm and are used for grasping an object.
• Basket/collectors are designed to hold multiple game pieces.  
• Lifts are assembled to lift other assembles vertically or to lift the robot off the ground.
• Roller intakes and conveyor belts are used to pick up game pieces.

Designing a Game Piece Assembly

Each game has its own unique set of requirements for play. There is no correct design for any given game, although there are assemblies which are more competitive. The most competitive assemblies are usually the ones which work effectively, quickly, and consistently.