Starter Bot - Programming Teleop
Last updated
Last updated
Our strategy for teleoperated mode was to make driving the robot as intuitive as possible. Having certain actions pre-programmed and assigned to buttons, like moving the arm into position to score on level 2 of the Shipping Hubs, will make the robot easier to control.
We decided to have buttons assigned to all 3 levels of the Shipping Hubs while scoring from the front and levels 2 and 3 from the back of the robot. Another decision we made was to have the intake motor controlled by the triggers. We chose to control the intake this way so that we could drive and pick up Freight at the same time.
Before getting started with programming we needed to create a configuration file. Below is an overview of how the robot is configured for the teleop code to function as expected:
For more in depth information on the configuration process check out Hello Robot - Configuration!
Items to consider when mapping out your gamepad:
What kind of input does the mechanism need?
Joysticks and Triggers input floating point data to your code allowing you to adjust the speed of a motor based on the pressure applied to the trigger or position of the joystick.
Buttons, Bumpers, and D-Pad provide boolean data to your code and are ideal for triggering a action such as rotating a motor to a set position.
What drivetrain are you using and what driving style do you want to use?
We decided the Freight Frenzy Starter Bot would be driven tank style.
Which input makes the most sense? Would pressing up on the d-pad be more intuitive for moving your arm up or down?
We chose to assign our backwards scoring presets to the bumpers because we liked the idea of backwards controls being on the back of the controller.
Not all controllers have buttons labeled the same way. Check the manufacturer's documentation for accurate button mapping.
Freight Frenzy Starter Bot controller layout:
More information on programming gamepads for use with your robot can be found at Hello Robot - Using Gamepads.
This section makes the assumption that you have learned some of the FTC programming basics by going through the Hello Robot guide. If you have not gone through this guide please walk through it before proceeding.
In Hello Robot- Basics of Programming Drivetrains we covered how to program arcade drive with one joystick, for this example we will be programming tank drive using two joysticks. The right joystick input will control forward and reverse motion of the right side motor and the left joystick will control the left motor in the same way. Similar to the arcade style driving tutorial, we will use the Dual Motor block to assign power values to our motors. This time, the motor's power value will be based on the Y-axis input from each joystick, as shown below.
Remember to reverse one of the motors and set the correct direction for forward movement of your robot. In our code we needed to reverse both motors with the dual drive block.
The control of our freight delivery arm is done by running the Core Hex Motor (REV-41-1300) to a specific position. We measured the number of encoder ticks needed to reach each of the five positions we had planned for our arm: low level, mid level, high level, high level from the back of the robot, and mid level from the back of the robot. For detailed instructions on how to measure encoder ticks on your robot and use the RUN_TO_POSITION
block see Hello Robot - Arm Control.
For all of our button inputs we used an if/else
statement. In the image below you can see the first two sections, one for setting the position of the arm to the ground and one for setting it to the height of level 1 on the Shipping Hub.
For the intake, we chose to use the triggers to control the speed of the motor spinning the mechanism. Since the triggers are easy to accidentally bump when holding the controller we decided we would only count the action as active if it was more than half way pressed. You can see this in the blocks intake mechanism code where the value of the right/left trigger is compared to 0.5.
The carousel mechanism is driven by a Smart Robot Servo (REV-41-1079), therefore the programming is slightly different for continuous motion. First, we programmed the Smart Robot Servo with the SRS Programmer (REV-31-1108) to be in continuous mode. You can reference the SRS Programmer Basics for a tutorial on how to switch modes on your Smart Robot Servo. Make sure you are using a set position
servo motor control block. Use Hello Robot - Servo Basics as an in-depth guide. We added this into the end of our long if/else
statement as seen below.
Below is the complete Blocks Program for the Freight Frenzy Starter Bot.
Click here to download the Freight Frenzy Starter Bot Blocks code.
This section makes the assumption that you have learned some of the FTC programming basics by going through the Hello Robot guide. If you have not gone through this guide please walk through it before proceeding.
In Hello Robot- Basics of Programming Drivetrains we covered how to program arcade drive with one joystick, for this example we will be programming tank drive using two joysticks. The right joystick input will control forward and reverse motion of the right side motor and the left joystick will control the left motor in the same way. The main difference this time is the motor's power value will be based on the Y-axis input from each joystick, as shown below.
Be sure to reverse one of the motors and set the correct direction for forward movement of your robot. In our code we needed to reverse both motors with the dual drive block.
The control of our freight delivery arm is done by running the Core Hex Motor (REV-41-1300) to a specific position. We measured the number of encoder ticks needed to reach each of the five positions we had planned for our arm: low level, mid level, high level, high level from the back of the robot, and mid level from the back of the robot. For detailed instructions on how to measure encoder ticks on your robot and use the ArmTarget =
statement see Hello Robot - Arm Control.
For all of our button inputs we used the if/else
statement shown below:
For the intake, we chose to use the triggers to control the speed of the motor spinning the mechanism. Since the triggers are easy to accidentally bump when holding the controller we decided we would only count the action as active if it was more than half way pressed. This is what the statementgamepad1.right_trigger>0.5)?1:((gamepad1.left_trigger>0.5)?-1:0);
is used to achieve.
The carousel mechanism is driven by a Smart Robot Servo (REV-41-1079), therefore the programming is slightly different for continuous motion. First, we programmed the Smart Robot Servo with the SRS Programmer (REV-31-1108) to be in continuous mode. You can reference the SRS Programmer Basics for a tutorial on how to switch modes on your Smart Robot Servo. Instead of using a motor.setPower
statement we will be using motor.setPosition
to make the servo rotate. You can find more information on how to program servos on the Hello Robot - Servo Basics page.
Below is the complete OnBot Java Program for the Freight Frenzy Starter Bot.
Device Name/Function | Device Type | Port |
---|---|---|
LeftDrive
HD Hex Motor
Motor/Encoder Port 0
RightDrive
HD Hex Motor
Motor/Encoder Port 1
Arm
Core Hex Motor
Motor/Encoder Port 2
Intake
Core Hex Motor
Motor/Encoder Port 3
DuckSpinner
Smart Robot Servo
Servo Port 0
Input
Function
Right Joystick
Right Side Drive Motor
Left Joystick
Left Side Drive Motor
Right Trigger
Intake In
Left Trigger
Intake Out
Right Bumper
High Level (Back Scoring)
Left Bumper
Mid Level (Back Scoring)
A / ✕
Intake Ground Position
B / ◯
High Level (Front Scoring)
Y / △
Mid Level (Front Scoring)
X / ☐
Low Level (Front Scoring)
D-Pad Right
Duck Spinner Counter Clockwise
D-Pad Left
Duck Spinner Clockwise
Port Type
Port Number
Device Type
Name
Motor
0
REVRoboticsUltraplantary
LeftDrive
Motor
1
REVRoboticsUltraplantary
RightDrive
Motor
2
REVRoboticsCoreHexMotor
Arm
Motor
3
REVRoboticsCoreHexMotor
Intake
Servo
0
Servo
DuckSpinner
I2C
0
IMU
imu