LogoLogo
  • Introduction
  • Getting Started with Control Hub
    • Connect to the Robot Controller Console
    • Updating Wi-Fi Settings
    • Connecting Driver Station to Control Hub
    • Wiring Diagram
    • Next Steps
  • Getting Started with Driver Hub
  • Adding More Motors
    • SPARKmini Motor Controller
    • Adding an Expansion Hub
  • Troubleshooting the Control System
    • General Troubleshooting
    • Control Hub Troubleshooting
    • Driver Hub Troubleshooting
      • Driver Hub Battery Troubleshooting
    • Expansion Hub Troubleshooting
    • Status LED Blink Codes
  • System Overview
    • Control Hub Specifications
    • Expansion Hub Specifications
    • Driver Hub Specifications
    • Port Pinouts
    • Protection Features
    • Cables and Connectors
      • XT-30 - Power Cable
      • JST VH - Motor Power
      • JST PH - Sensors and RS485
    • Integrated Sensors
    • Dimensions and Important Component Locations
  • Updating and Managing
    • Managing Wi-Fi on the Control Hub
    • REV Hardware Client
    • Updating Firmware
      • Firmware Changelog
    • Updating Operating System
      • Control Hub Operating System Changelog
    • Updating Robot Controller Application
      • Updating Robot Controller Application via Android Studio
    • Updating the Driver Hub
      • Driver Hub OS - Change Log
    • Accessing Log Files
    • Android Studio - Deploying Code Wirelessly
  • Hello Robot - Intro to Blocks Programming
    • Welcome to Hello Robot!
    • Where to Program - Client vs. Browser
      • What is an OpMode?
    • Setting up a Configuration
      • Common Errors in Configuration
    • Using a Gamepad
    • Part 1: Tackling the Basics
      • Tackling the Basics Directory - Blocks
      • Creating an OpMode - Blocks
      • Programming Essentials
      • Programming Servos
        • Programming Servo Basics
        • Using a Gamepad with a Servo
        • Programming Servo Telemetry
      • Programming Motors
        • Programming Motors Basics
        • Programming a Motor with a Gamepad
        • Programming Motor Telemetry
      • Programming Touch Sensors
      • Programming Color Sensors
        • Color Sensor Telemetry
        • Detecting Color
    • Part 2: Robot Control
      • Robot Control Blocks Directory
      • Programming Drivetrain Motors
      • Arcade Style TeleOp - Blocks
        • Establishing Variables in Blocks
        • Motor Power vs. Robot Movement
        • Programming Arcade Drive
      • Arm Control - Blocks
        • Adding a Limit Switch
      • Robot Control Full Program
    • Part 3: Autonomous and Encoders
      • ElapsedTime - Blocks
        • ElapsedTime Setup
        • ElapsedTime Logic
        • ElapsedTime - Multiple Movements
      • Encoder Basics
      • Drivetrain Encoders - Blocks
        • Converting Encoder Ticks to a Distance
        • Moving to a Target Distance
        • Setting Velocity
        • Turning the Drivetrain Using RUN_TO_POSITION
      • Arm Control with Encoders - Blocks
        • Estimating the Position of the Arm
        • Calculating Target Position
        • Using Limits to Control Range of Motion
    • Part 4: Going Beyond!
      • Exploring Functions
      • Programming Mecanum - Simplified
      • Programming Mecanum - Refined
  • Hello Robot - Intro to OnBot Java Programming
    • Welcome to Hello Robot!
    • Where to Program - Client vs. Browser
      • What is an OpMode?
    • Setting up a Configuration
      • Common Errors in Configuration
    • Using a Gamepad
    • Part 1: Tackling the Basics
      • Tackling the Basics Directory - OnBot
      • Creating an OpMode - OnBot
      • Programming Essentials
      • Programming Servos
        • Programming Servo Basics
        • Using a Gamepad with a Servo
        • Programming Servo Telemetry
      • Programming Motors
        • Programming Motor Basics
        • Programming a Motor with a Gamepad
        • Programming Motor Telemetry
      • Programming Touch Sensors
    • Part 2: Robot Control
      • Robot Control OnBot Java Directory
      • Programming Drivetrain Motors
      • Arcade Style TeleOp - OnBot Java
        • Establishing Variables in OnBot Java
        • Motor Power vs. Robot Movement
        • Programming Arcade Drive
      • Arm Control - OnBot Java
        • Adding a Limit Switch
      • Robot Control Full Program
    • Part 3: Autonomous and Encoders
      • ElapsedTime - OnBot Java
        • ElapsedTime Setup
        • ElapsedTime Logic
        • ElapsedTime - Multiple Movements
      • Encoder Basics
      • Drivetrain Encoders - OnBot Java
        • Converting Encoder Ticks to a Distance
        • Moving to a Target Distance
        • Setting Velocity
        • Turning the Drivetrain Using RUN_TO_POSITION
      • Arm Control with Encoders - OnBot Java
        • Estimating the Position of the Arm
        • Calculating Target Position
        • Using Limits to Control Range of Motion
  • Sensors
    • Introduction to Sensors
    • Digital
    • Analog
    • I2C
      • IMU
        • Orientating the IMU
      • Adding an External IMU to your Hub
    • Encoders
      • REV Motor Encoders
      • Through Bore Encoder
    • Using 3rd Party Sensors
      • Sensor Compatibility Chart
  • Useful Links
    • REV DUO Build System
  • Legacy Documentation
    • Configuring Your Android Devices
    • Expansion Hub with Android Device Robot Controller
      • Driver Station and Robot Controller Pairing
      • Wiring Diagram
      • Configuration
    • REV Hub Interface Software
Powered by GitBook
On this page
  • Touch Sensor Basics
  • Adding Telemetry
  • Touch Sensor as a Limit Switch
  • Reversing it

Was this helpful?

Export as PDF
  1. Hello Robot - Intro to Blocks Programming
  2. Part 1: Tackling the Basics

Programming Touch Sensors

PreviousProgramming Motor TelemetryNextProgramming Color Sensors

Last updated 11 months ago

Was this helpful?

This section applies to the use of the REV or . Requirements may vary when using other 3rd party touch sensors.

The REV Touch Sensor must be configured to digital port 1, 3, 5, or 7.

It is recommended to create a new OpMode while following this tutorial. Ours is named HelloRobot_TouchSensor!

The touch sensor block is now found under the "Sensors" dropdown as seen below:

Touch Sensor Basics

Let's start by breaking down how a touch sensor works at its core!

Remember what sensors and motors are available in your program are determined by your configuration! Double check the correct configuration is active if you do not see a device list.

The information collected by a touch sensor comes in two states, also known as binary states. This information is perfect to use with a conditional statement like an if/else statement.

The block collects the binary TRUE/FALSE state from the touch sensor and acts as the condition for the if/else statement.

Let's take a look at our touch sensor block paired with our block:

Take a moment to think what this code is asking the robot to do. We could read this line of code as "If the touch sensor is pressed do ____, else if the touch sensor is not pressed do _____."

Adding Telemetry

It's always helpful for us to be able to see what the robot thinks its doing on our Driver Hub's screen. To do this, let's request the robot shares some telemetry data while our program is active.

What happens if you run the program right now?

When on the default "Telemetry" block the information provided is not helpful for the robot to communicate with us. Therefore we need to change "key" and "text" to match the desired information.

The "key" should be something related to which sensor, motor, or other device we are receiving information from. Meanwhile "text" will tell us what is happening based on the state of our touch sensor and our if/else statement.

Let's give our code another try to see what happens on the Driver Hub's Screen. Did you see something like the following?

Remember its up to us to decide what our telemetry readout says. With that in mind we could change it so our robot says "Hello World" when the button is pressed:

Take a moment to think about how else telemetry data could be used with your robot before moving on to the next section!

Touch Sensor as a Limit Switch

At the moment, our robot does not have any senses to help navigate the world around it like you might. However, that's the key advantage to adding sensors to our design.

Reversing it

In the above example the if/else is checking first for if the touch sensor is pressed. The full statement could be read as "If the touch sensor is pressed set the motor's power to 0 else, if it is not pressed, set the power to 0.3".

Give it a try!

We can access the "Telemetry" blocks under our "Utilities" dropdown on the menu. Look for the block to be added in each section of the if/else statement.

For the touch sensor, one of the most common uses is for it to act as a . This will help the robot know when it needs to halt the movement of a mechanism, like an arm or lift, that's at its limit similar to how your nerves help to tell your brain to do the same.

We can test this idea by adding on to our existing if/else statement. This time we are going to ask our motor to move until our sensor is pressed using the block:

There may be situations where we want our program to read if the touch is NOT pressed first. Let's take a quick look at how that would function using the block from the "Logic" menu.

Touch Sensor
Limit Switch
limit switch