pxt-calliope/docs/lessons/charting/activity.md

Activity

Measure the acceleration on the micro:bit in the "x" direction.

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Welcome! This activity will teach how to use the micro:bit to chart the acceleration in the "x" direction. Let's get started!

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Let's measure acceleration (mg) in the "x" direction. Get the acceleration value (milli g-force), in one of three specified dimensions.

input.acceleration(Dimension.X)

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Use the plot bar chart to visualize the acceleration on the LED screen of the micro:bit in the specified range. You implement plot Bar Graph to display a vertical bar graph based on the "value" and "high" value. Then you must insert acceleration in the X dimension to measure the acceleration.

basic.forever(() => {
    led.plotBarGraph(input.acceleration(Dimension.X), 0)
})

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Notice that moving the micro:bit in the simulator from left to right (x direction) changes the values beneath the micro:bit in a range from 1023 to -1023 as measured in milli-gravities. By hovering over the micro:bit from left to right, you can observe changing values beneath the micro:bit simulator. Also, the LEDs shown on the Bar Graph fluctates based on the movement of the micro:bit simulator in the x direction. The line underneath the micro:bit simulator reflect the acceleration in the x direction.

NOTE: The colors of the charts reflect the color of the micro:bit simulator. In this instance, the micro:bit is yellow. So the color of the data line reflects the color of the micro:bit

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Vigorously move the micro:bit in the micro:bit simulatator by moving the micro:bit image from side to side. Every time the micro:bit moves in the x direction in the simulator, you are generating data points that can be reviewed in Excel. The more attempts to move the micro:bit from side to side, the more data being saved in Excel. After you have vigarously moved the micro:bit simulator from side to side for a sufficient amount of time, you are ready to graph or chart the accceleration of the micro:bit. We want a printout of our acceleration on Excel that can be graphed in Excel.

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We want to chart the data collected by using a tool in Excel.

The final part of this experiment is opening and reviewing the data in the Excel CSV file. Simply click on the line beneath the simulator. A CSV file will be generated to display the data points collected by moving the micro:bit in the X direction. Then click or tap on the data Excel file that was downloaded to your local Downloads Folder.

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First, click or tap on the first two columns (A, B) to include the time of the data being collected; b) the results of acceleration data on the micro:bit

Use the Recommended Charts command on the Insert tab to quickly create a chart that’s just right for your data.

• Select the data that you want to include in your chart.

• Click Insert > Recommended Charts.

• On the Recommended Charts tab, scroll through the list of chart types that Excel recommends for your data. Pick the scatter plot.

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Excellent, you're ready to continue with the challenges

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