AscendRobotics/AscendData · Datasets at Hugging Face

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The shaft acts as a cross-brace and helps hold game objects.
Pneumatics
These pack a punch
In Vex Robotics, teams can use two things to do active mechanical work: motors and pneumatics. Pneumatics use the power of compressed air to activate mechanisms on the robot. However, each actuation uses up a little bit of air each time, so the force from pneumatics slowly decreases throughout a match. Despite this, they are very useful in a variety of mechanisms.
For example, here's a pneumatic that is used to activate wings on an VEX Over Under robot:


To set up a basic pneumatic system, you need three components:
* Air tank: Stores compressed air
* Solenoid: Directs compressed air
* Piston: Uses compressed air
Here's a simple pneumatic system. In summary, compressed air is stored in the air tank to the left, and then directed by the solenoid to either expand or contract the piston. The air tank is filled up with a bicycle pump or air compressor through the Schrader valve. From there, pneumatic tubing connects it to the double-acting solenoid. The solenoid directs the air to one of two output valves that lead to the two sides of the piston. Also, there's a plug in the right side of the solenoid to prevent the air from coming out of the system.


Simple pneumatic system setup (the new pneumatics)
For information on how to code the pneumatic system, check out this page:
🌬
Coding Pneumatics
Best Practices
Here's a few tips to keep in mind while building with pneumatics:
* Keep the air hose between the solenoid and pneumatic piston as short as possible, to minimize the amount of air lost in each actuation.
* Pneumatic pistons are designed to withstand an incredible amount of force parallel to the direction they extend in, but they are not designed to resist bending.
* Tighten each valve fitting all the way to prevent leaks. If there is a leak, and you can't find where, apply a small amount of soapy water to each valve fitting connection. If the soapy water starts to bubble at a valve fitting, then air is leaking there.
*
* * So, that's where the leak is!
Additional Mechanisms
3D Printing
Non-functional, but cool
Unfortunately, 3D-printed parts with a function are not permitted on the robot. However, you are allowed to have decorations or license plate holders that are 3D-printed.
In fact, we strongly recommend these license plate holders, because they make it very easy to change colors between matches, saving time.


3D printed license plate holder
Here's the file; no supports are needed when 3D printing it.
Robotics-license-plate-holder3.stl107KB
Binary

Ratchets
Ratchets allow certain mechanisms on the robot to only activate when a motor spins in one direction. By combining multiple ratchets, a team can add more functionality to their robot.
The basic premise of a ratchet is that a gear or sprocket is attached to a shaft such that it can spin freely around it. When the shaft rotates, the gear or sprocket does not necessarily rotate with it.
There is also a smaller gear, right next to the primary gear/sprocket that does rotate with the shaft. A small screw on the primary gear/sprocket is then rubber banded so that it "catches" on the smaller sprocket when it turns in one direction, but not in the other.


Outer sprocket rotates; the shaft does too


Outer sprocket rotates; the shaft stays still
To build a simple ratchet, first obtain and assemble the following. Note that a 6-tooth 8P sprocket will usually work for the smaller gear. Additional testing might be required to find the best spacing on the screw in the picture to the right. Also, the larger sprocket can be swapped out for a gear.




Make sure to use the circular inserts!
Now, put both of the above sprockets on the same shaft. The next step is to zip tie a small rubber band to the large sprocket, as shown below, and wrap it around the screw. This keeps the screw locked into the smaller sprocket when the axle is turning.
Catapults
Launching stuff
Catapults are a common launching mechanism. They are simple, easy to build, and quite effective at launching all sorts of game objects.
Before we can get started with catapults, we first have to go over slip gears. These are gears with either one or two sections of teeth shaved off, like so:


The simplest catapult possible is a slip gear directly linked to a catapult arm. The slip gear pulls back the catapult to a certain point with the teeth that are on it. Then, when the section of the slip gear with the teeth shaved off reaches the gear on the catapult, the two gears disengage. At that point, the rubber bands on the catapult launch it forwards, along with any game object on the catapult.
Here's a demonstration, courtesy of team 491A and the Purdue Sigbots Wiki:
Intakes
Intakes are mechanisms designed to pick up different game objects and put them into a robot. There are a wide variety of intakes, and we'll show you a few of them here.
The first common type of intake uses an array of flex wheels on a rotating arm. Flex wheels have a lot of grip, which makes them good at grabbing game objects. Additionally, the flex wheels can lift up and down, allowing game objects to come into the robot. Note the cross-bracing and C-channel across the intake that stabilizes it.


Simple Spin Up intake
Here's another example of a flex wheel intake, but this one is vertical instead of horizontal:


Image: 62A, BLRS wiki
Another common type of intake uses rubber bands wrapped around sprockets as shown below. Rubber bands conform to the shape of the object in the intake more than flex wheels do, which can be helpful depending on the game object and intake spacing.


While flex wheels and rubber band sprockets are the majority of intakes, teams can also wrap a single layer of anti-slip mat around a rubber band intake for better durability.
Lifts
No, not that kind of lift.
Lifts are any mechanism that raises one part of the robot up, usually to score points or to achieve some other purpose.
One of the most common types of lifts is the four-bar. This simple lift raises up a small bar, while keeping it parallel to it's initial position.
Another variant of the four-bar is the double reverse four-bar (DR4B). This type of lift uses two four-bars in tandem that lift the desired mechanism up even higher.
To build a four-bar, connect two C-channels in parallel as shown in the videos.


Coding
We'll use VEXcode Pro V5
Getting Started
We'll show you how to get started coding the robot using VEXCode Pro and C++
First, download VEXCode Pro and install it. Then, open the program and create a new project.
Start Coding
Let's write a simple C++ program to set up the robot:
#include "vex.h"

using namespace vex;

int main() {
vexcodeInit(); //leave this line here! Everything else has to come after it.

The shaft acts as a cross-brace and helps hold game objects.

Pneumatics

These pack a punch

In Vex Robotics, teams can use two things to do active mechanical work: motors and pneumatics. Pneumatics use the power of compressed air to activate mechanisms on the robot. However, each actuation uses up a little bit of air each time, so the force from pneumatics slowly decreases throughout a match. Despite this, they are very useful in a variety of mechanisms.

For example, here's a pneumatic that is used to activate wings on an VEX Over Under robot:

To set up a basic pneumatic system, you need three components:

* Air tank: Stores compressed air

* Solenoid: Directs compressed air

* Piston: Uses compressed air

Here's a simple pneumatic system. In summary, compressed air is stored in the air tank to the left, and then directed by the solenoid to either expand or contract the piston. The air tank is filled up with a bicycle pump or air compressor through the Schrader valve. From there, pneumatic tubing connects it to the double-acting solenoid. The solenoid directs the air to one of two output valves that lead to the two sides of the piston. Also, there's a plug in the right side of the solenoid to prevent the air from coming out of the system.

Simple pneumatic system setup (the new pneumatics)

For information on how to code the pneumatic system, check out this page:

🌬

Coding Pneumatics

Best Practices

Here's a few tips to keep in mind while building with pneumatics:

* Keep the air hose between the solenoid and pneumatic piston as short as possible, to minimize the amount of air lost in each actuation.

* Pneumatic pistons are designed to withstand an incredible amount of force parallel to the direction they extend in, but they are not designed to resist bending.

* Tighten each valve fitting all the way to prevent leaks. If there is a leak, and you can't find where, apply a small amount of soapy water to each valve fitting connection. If the soapy water starts to bubble at a valve fitting, then air is leaking there.

*

* * So, that's where the leak is!

Additional Mechanisms

3D Printing

Non-functional, but cool

Unfortunately, 3D-printed parts with a function are not permitted on the robot. However, you are allowed to have decorations or license plate holders that are 3D-printed.

In fact, we strongly recommend these license plate holders, because they make it very easy to change colors between matches, saving time.

3D printed license plate holder

Here's the file; no supports are needed when 3D printing it.

Robotics-license-plate-holder3.stl107KB

Binary

Ratchets

Ratchets allow certain mechanisms on the robot to only activate when a motor spins in one direction. By combining multiple ratchets, a team can add more functionality to their robot.

The basic premise of a ratchet is that a gear or sprocket is attached to a shaft such that it can spin freely around it. When the shaft rotates, the gear or sprocket does not necessarily rotate with it.

There is also a smaller gear, right next to the primary gear/sprocket that does rotate with the shaft. A small screw on the primary gear/sprocket is then rubber banded so that it "catches" on the smaller sprocket when it turns in one direction, but not in the other.

Outer sprocket rotates; the shaft does too

Outer sprocket rotates; the shaft stays still

To build a simple ratchet, first obtain and assemble the following. Note that a 6-tooth 8P sprocket will usually work for the smaller gear. Additional testing might be required to find the best spacing on the screw in the picture to the right. Also, the larger sprocket can be swapped out for a gear.

Make sure to use the circular inserts!

Now, put both of the above sprockets on the same shaft. The next step is to zip tie a small rubber band to the large sprocket, as shown below, and wrap it around the screw. This keeps the screw locked into the smaller sprocket when the axle is turning.

Catapults

Launching stuff

Catapults are a common launching mechanism. They are simple, easy to build, and quite effective at launching all sorts of game objects.

Before we can get started with catapults, we first have to go over slip gears. These are gears with either one or two sections of teeth shaved off, like so:

The simplest catapult possible is a slip gear directly linked to a catapult arm. The slip gear pulls back the catapult to a certain point with the teeth that are on it. Then, when the section of the slip gear with the teeth shaved off reaches the gear on the catapult, the two gears disengage. At that point, the rubber bands on the catapult launch it forwards, along with any game object on the catapult.

Here's a demonstration, courtesy of team 491A and the Purdue Sigbots Wiki:

Intakes

Intakes are mechanisms designed to pick up different game objects and put them into a robot. There are a wide variety of intakes, and we'll show you a few of them here.

The first common type of intake uses an array of flex wheels on a rotating arm. Flex wheels have a lot of grip, which makes them good at grabbing game objects. Additionally, the flex wheels can lift up and down, allowing game objects to come into the robot. Note the cross-bracing and C-channel across the intake that stabilizes it.

Simple Spin Up intake

Here's another example of a flex wheel intake, but this one is vertical instead of horizontal:

Image: 62A, BLRS wiki

Another common type of intake uses rubber bands wrapped around sprockets as shown below. Rubber bands conform to the shape of the object in the intake more than flex wheels do, which can be helpful depending on the game object and intake spacing.

While flex wheels and rubber band sprockets are the majority of intakes, teams can also wrap a single layer of anti-slip mat around a rubber band intake for better durability.

Lifts

No, not that kind of lift.

Lifts are any mechanism that raises one part of the robot up, usually to score points or to achieve some other purpose.

One of the most common types of lifts is the four-bar. This simple lift raises up a small bar, while keeping it parallel to it's initial position.

Another variant of the four-bar is the double reverse four-bar (DR4B). This type of lift uses two four-bars in tandem that lift the desired mechanism up even higher.

To build a four-bar, connect two C-channels in parallel as shown in the videos.

Coding

We'll use VEXcode Pro V5

Getting Started

We'll show you how to get started coding the robot using VEXCode Pro and C++

First, download VEXCode Pro and install it. Then, open the program and create a new project.

Start Coding

Let's write a simple C++ program to set up the robot:

#include "vex.h"

using namespace vex;

int main() {

vexcodeInit(); //leave this line here! Everything else has to come after it.