ae3ae18585
- Redesign /resources as sectioned hub with category pages - Migrate 645 Squarespace CDN images to local /images/content/ - Create 9 new news/blog posts with event photos - Fix blog post slugs (rename gibberish filenames) - Rename Design Blog to Design Blogs across site - Remove education page, replace with Platform in nav - Redesign rover repair request form with dynamic rover entries - Add school search combobox to contact, store, and repair forms - Extract shared KNOWN_SCHOOLS data - Make /rover-expansion-3d-printing dynamically pull from MDX - Add related resources sections to product pages - Fix homepage broken /quote links to /store - Store page: sample kit cards, inline quote builder, mailing list opt-in
93 lines
2.1 KiB
Plaintext
93 lines
2.1 KiB
Plaintext
---
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title: "Activity: Stop On Colour Change"
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date: "2021-06-03"
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categories: ["Activities", "All"]
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tags: ["Colour Sensors", "Branching", "Iteration"]
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excerpt: "Learn branching, iteration, and how to use the colour sensors."
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featuredImage: "/images/resources/stop-on-colour-change.png"
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---
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Program the rover to keep moving forward until it detects a change of floor colour with the colour sensors. Once it detects this colour, stop the rover.
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####
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Relevant Coding Skills
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Branching
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-->
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Iteration
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Functions
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Variables
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-->
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Algorithm Design
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-->
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Maths
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####
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Relevant Rover Concepts
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Ultrasonic
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-->
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IR
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-->
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Colour
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Gyroscope
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Accelerometer
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Motors
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LEDs
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-->
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Buzzer
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-->
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Activity Demonstration
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### Setup
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For this exercise we recommend a strip of tape stuck to the floor that contrasts the floor colour. It doesn't have to be tape, all that matters is there is a clear change in colour for the rover to detect. An alternative solution is to use a piece of coloured paper.
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Your solutions should work no matter how far from the tape the rover starts. Make sure to test the same code from multiple starting positions.
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### Here’s Our Approach
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#### **Stage 1**
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First we need the rover to drive forward towards a change in colour. We tell the rover to move forward with a start moving motor block.
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#### **Stage 2**
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As the rover drives forward, we need to be constantly checking the colour sensor. Use a repeat until loop block where the condition is set to detect the desired colour. Our code is looking for the brightness of the white tape.
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#### **Stage 3**
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The rover will keep checking the colour sensor in the loop block until the condition is true. After the repeat we stop all motors.
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#### Note
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If the simple colour sensor blocks aren’t working we may need to use a different comparison block to check more detailed readings from the sensor. Use the rover sensor view to identify the one that will work best for you.
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Example Code 1
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Example Code 2
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