How do I flip a red auto to get a blue auto — Sharp AI

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How do I flip a red auto to get a blue auto

The indexed documentation does not contain instructions on how to flip a red autonomous program to a blue autonomous program.

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1

Pedro Pathing > Example Auto

Pedro Pathing·No licence published — summarised, never reproduced

Summarised above in Sharp AI’s own words. The original text is not reproduced here — open the source to read it.

Open Pedro Pathing

2

*FIRST* Tech Challenge Field Coordinate System Definition > Field Configuration Examples > Square Field (Inverted ALLIANCE AREA)

FTC Docs·BSD 3-Clause

(Figure: The DECODE game field

The DECODE game field is essentially a square field, but the red and blue ALLIANCE AREAS are swapped from their typical configuration (red ALLIANCE AREA on the left when viewed from the audience). In this configuration, the X and Y axes are "inverted" in which direction the positive axis points. This is still consistent with the field coordinate system definition, but the field is inverted.

The field is oriented such that the Red Wall is on the left as seen from the audience.
The Y axis points across the field from the Red Wall towards the Blue Alliance.
The X axis points towards the audience to the front of the field.)

3

*FIRST* Tech Challenge Field Coordinate System Definition > Field Configuration Examples > Diamond Field

FTC Docs·BSD 3-Clause

(Figure: The FIRST RES-Q game field

In a diamond field configuration the two Alliance walls are adjacent. The field is rotated 45 degrees such that both Alliances face the audience. From the audience perspective the field forms a diamond shape. The Red Wall will be on the right as seen from the audience. The Y axis points across the field as seen from the Red Wall. The X axis points to the Blue Alliance.)

4

*FIRST* Tech Challenge Field Coordinate System Definition > Field Configuration Examples > Square Field

FTC Docs·BSD 3-Clause

(Figure: The Into The Deep game field

In a square field configuration the two Alliances face each other across the field.

The field is oriented such that the Red Wall is on the right as seen from the audience.
The Y axis points across the field from the Red Wall towards the Blue Alliance.
The X axis points away from the audience to the rear of the field.)

5

*FIRST* Tech Challenge Field Coordinate System Definition > Reference Frame

FTC Docs·BSD 3-Clause

The reference frame for this definition is the field perimeter wall, adjacent to the red Alliance Area, known here after as the Red Wall. The definition is from the perspective of a person, standing outside the field, in the center of Red Wall, looking towards the center of the field.

Note: If the red Alliance Area is ever adjacent to two perimeter walls, the Red Wall will be the one with most contact with the Alliance Area. If the red Alliance Area is ever adjacent to two perimeter walls equally, then the most clockwise of the two walls will be considered to be the Red Wall.

6

*FIRST* Tech Challenge Field Coordinate System Definition > Coordinate Position Example

FTC Docs·BSD 3-Clause

Let's consider the coordinates (-58.3727, 55.6425, 29.5) in inches on the DECODE field, which is a square field with inverted red/blue. Given the order of coordinates then X = -58.3727, Y = 55.6425, and Z = 29.5.

The X axis value of -58.3727 is located deep in the back (away from the Audience Wall) of the field.
The Y axis value of 55.6425 would be located closer to the Blue Wall, about a 3/4 tile length from the Blue wall.
The Z axis value of 29.5 is 29.5 inches above the field tiles.

This set of coordinates is the center of the Red Goal AprilTag on the Red Goal.

7

*FIRST* Tech Challenge Field Coordinate System Definition > Field Configuration Examples

FTC Docs·BSD 3-Clause

Below are two examples illustrating the Field Coordinate System for different FIRST Tech Challenge field configurations.

Note: In both field configurations the red Alliance is facing out along the positive Y axis, and the Z axis points up from the center of the field.

8

*FIRST* Tech Challenge Field Coordinate System Definition > Additional Information

FTC Docs·BSD 3-Clause

See this Wikipedia article on Cartesian coordinate system (https://en.wikipedia.org/wiki/Cartesian_coordinate_system#Three_dimensions) in three dimensions. The Field Coordinate System rotation convention comes from the right hand rule (https://en.wikipedia.org/wiki/Right-hand_rule) of classic geometry.

Robots with a webcam can use AprilTags to determine where an AprilTag is located with respect to the robot. Since AprilTags are in known locations on the field, you can also determine the location of the robot on the field.

Robots can use an inertial measurement unit (IMU) to measure rotations about axes with respect to the robot. See IMU axes definition. The yaw value from the IMU, also known the heading, measures rotation about the Z axis which points up from the robot. You can use the IMU to determine which direction a robot is facing.

9

*FIRST* Tech Challenge Field Coordinate System Definition

FTC Docs·BSD 3-Clause

Summary: The FIRST Tech Challenge Field Coordinate System is a Cartesian Coordinate System of three dimensions. The X and Y axes will refer to a position on the field and the Z axis a height above the field.

This document defines the Field Coordinate System for a FIRST Tech Challenge playing field. This definition can be used for consistent field-centric navigation, target localization and path planning.

10

*FIRST* Tech Challenge Field Coordinate System Definition > Coordinate System > X Axis

FTC Docs·BSD 3-Clause

Looking at the origin from the Red Wall, the X axis extends through the origin point and runs to the right and left, parallel with the Red Wall. The X axis values increase to the right.

Looking at the origin from the Red Wall, the Y axis extends through the origin point and runs out and in, perpendicular to the Red Wall. Increasing Y values run out (away) from the Red Wall.

11

Automatically Loading a Driver Controlled Op Mode

FTC Docs·BSD 3-Clause

After the Autonomous program ends, the Driver Station changes the queued OpMode to the TeleOp program which was preselected before the start of Autonomous. The auto-preselection will be aborted if the user presses stop (either the main stop or init stop buttons). It will only transition if the OpMode either self-exits, or is terminated by the 30s timer. Drive Teams must still press Init and start the op mode manually, for safety reasons.

Should you wish to not be required to manually enable and configure the preselection feature each time you want to run your Autonomous program, you can edit your OpMode annotation to include preselectTeleOp="My TeleOp Name". The Driver Station will then automatically activate the preselection feature and configure it to preselect the OpMode specified in the annotation.

@Autonomous(name="Blue Alliance Auto", group="Pushbot", preselectTeleOp="BlueAllianceTeleOp")

Blocks users can make use of this feature as well, through a new dropdown in the Blocks program editor.

(Figure: You can preselect a teleop op mode mode using the Blocks editor.)

Note that there is an option in the Settings menu of the Driver Station app called “OpMode Auto Queue”. If this option is enabled, then the Driver Station will automatically load an autonomous op mode’s preselected teleop op mode as designated by the preselectTeleOp parameter. If this option is disabled, then the Driver Station will not automatically load the preselected teleop op mode. If the “Op Mode Auto Queue” option is disabled, a team can still select a teleop op mode by using the preselect button on the main Driver Station activity.

(Figure: If the OpMode Auto Queue option is enabled, the Driver Station will automatically load the preselectTeleOp op mode in landscape mode.)

(Figure: If the OpMode Auto Queue option is enabled, the Driver Station will automatically load the preselectTeleOp op mode in portrait mode.)

12

Color Processing Color Sensor > Sample OpMode > Running the Sample OpMode

FTC Docs·BSD 3-Clause

On the Driver Station:

Select the Autonomous OpMode that you just saved or built.
Turn off the automatic 30-second match timer (green slider).
Touch INIT only.

The OpMode should give Telemetry, stating the main "matched" color inside the Region of Interest.

(Figure: Driver Station Telemetry)

Move the camera around, and watch the Telemetry area on the Driver Station screen. It should state "BLUE" when pointing at a blue object, and likewise should identify other common colors.

It's working! You have a color sensor in your robot camera. Think about how to use this in the FTC Robot Game.

Skip the next two sections if you already know how to use FTC previews.

13

Color Spaces > RGB Color Space

FTC Docs·BSD 3-Clause

RGB is a common Color Space, easy to understand. Its 3 components are:

Red (0 - 255)
Green (0 - 255)
Blue (0 - 255)

(Figure: RGB Color Wheel)

Pure Red has values 255 red, 0 green, 0 blue. Pure Green has 0 red, 255 green, 0 blue.

Magenta is a blend of Red and Blue, so its values are 255 red, 0 green, and 255 blue.

Here's a useful way to visualize the RGB Color Space, with one axis for each component:

(Figure: RGB Cube Visualization)

Each near-side external face of this box has the maximum value for one component. Every shade of color on the top face, for example, has a Blue component of 255.

The nearest corner is White, with RGB values of (255, 255, 255). Namely, full values of Red, Green and Blue light will combine to appear as white light.

Where is Black? It's the opposite corner, at the origin, hidden in this view. Its values are (0, 0, 0) -- no color at all.

This RGB system is used only for light-based colors, including video. It does not apply for painted colors, or printed colors, which use other color systems.

Tip: Mixing red paint, green paint and blue paint will not create white paint!

Technical information is available at Wikipedia Color Spaces (https://en.wikipedia.org/wiki/RGB_color_spaces).

14

HuskyLens Intro for *FIRST* Tech Challenge > Multi-Color Training

FTC Docs·BSD 3-Clause

After completing the above tutorial with a single trained color, you may wish to train two colors (e.g. a Red shade and a Blue shade).

This would avoid the need for multiple color-training sessions during an FTC tournament. With single-color, you would train for Red before playing an FTC match as Red Alliance, and train for Blue before playing as Blue Alliance.

With multi-color, your Red-Alliance Autonomous OpMode could seek Red as Color:ID1, for example, and your Blue-Alliance Autonomous OpMode could seek Blue as Color:ID2.

The HuskyLens instructions for learning multiple colors are posted online (https://wiki.dfrobot.com/HUSKYLENS_V1.0_SKU_SEN0305_SEN0336#target_19). You could try to follow those, or use the equivalent description here. Again, some practice may be required!

Reminder: on the top of the HuskyLens, the wheel at the left side is called the Function button (actually a dial and button). At the right side is the small Learning button.

Step 1. Dial the Function button to the right or left until “Color Recognition” is displayed at the bottom of the screen.

Long press (press and hold) the Function button to select Color Recognition.

Step 2. This brings up the next menu, containing the choice “Learn Multiple”. If needed, dial the Function button to highlight “Learn Multiple”.

Short press (press and release) the Function button to select Learn Multiple.

This brings up the OFF-ON slider bar for “Learn Multiple”. If needed, dial the Function Button to move the blue square to the right side of the blue slider bar. See yellow arrow:

(Figure: HuskyLens - Learn Multiple)

Short press the Function button to set “Learn Multiple” to ON.

Step 3. Dial the Function button to the left, and short press to select “Save & Return”.

At the screen prompt “Do you want to save the parameters?” or “Do you save data?”, short press the Function button to select “Yes”. This saves the mode (again) as “Learn Multiple” and exits the settings menu.

Now ready for learning!

Step 4. As before, point the plus-sign “+” icon in the center of the HuskyLens screen at your object’s main color area. A white frame appears on the screen, targeting the main color. Aim the HuskyLens so the white frame includes only the target color.

15

AprilTag Localization > Reference Frames

FTC Docs·BSD 3-Clause

In the above example. the yaw angle is given as (approximately) -90 degrees. But the camera is facing in the negative X direction, thus has a heading or yaw angle of -180 degrees in the official FTC field coordinate system :

(Figure: FTC Field Coordinate System)

This sample OpMode uses a reference frame (coordinate system) that may be different than what you expect from other FTC navigation applications, including IMU or robot axes , odometry device axes, and the FTC field system (shown above). These differences typically result in basic and obvious changes in axis direction, axis swapping, and orthogonal angles (90-degree increments).

Learn and incorporate these differences into your OpMode, for the given scenario of your AprilTag localization. Manually adjust values as needed to accomplish your specific navigation goals.

Evaluate the accuracy and reliability of AprilTag navigation, with and without offsets, smoothing and other adjustments. Some FTC teams use multiple data sources for navigation. Base your robot strategy on capabilities demonstrated through extensive testing and refinement.

16

HuskyLens Intro for *FIRST* Tech Challenge > Competition Notes > 2. Color

FTC Docs·BSD 3-Clause

The above trained blue object is not the same shade of blue as the blue Spike Mark. This difference increases the chance of a distinct and correct recognition of the object color.

In this game, the Competition Manual specifically allowed the Team Prop to be a different shade of Red or Blue, compared to the official tape color of Spike Marks.