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Power Budget Sizer

Run the Power Budget Sizer MicroSim Fullscreen

You can include this MicroSim on your website using the following iframe:

<iframe src="https://dmccreary.github.io/robot-arm/sims/power-budget-sizer/main.html"
        height="524px" width="100%" scrolling="no"></iframe>

Description

Add the motor currents of four arm setups, apply the 1.25 margin factor, type the current the supply must deliver, then choose among three supplies. Used in Chapter 3.

The orange blocks are the motor currents laid end to end, so their combined length is the total. After you commit a number, the sim puts the blocks on an ampere axis, adds the margin as a striped block, marks the needed current with a red line, and shows the three supply ratings as flags.

All motor currents are illustrative. The supply voltage is 5 V in every setup, and the margin factor is the 1.25 used in the chapter.

Lesson Plan

Grade level: Middle school and up (age 12+). Time: 5 to 10 minutes.

  1. List and add. Read the motor currents and add them to get the total.
  2. Apply the margin. Multiply the total by 1.25. Type the result in amperes and press Check. An answer within 0.05 A counts, and you get one attempt per setup.
  3. Choose a supply. Press one of the three supply buttons. The flags turn green for ratings at or above the needed current and red for ratings below it. This choice is not scored.
  4. Review. The last screen lists the needed current and the adequate supply for all four setups. Mastery is 3 of 4.
  5. Think about it. Setup 4 needs 1.125 A. Why is the 1 A supply not good enough, even though it is close?

Specification

The learning objective, evidence of mastery and content for this MicroSim are specified in Chapter 3: Electricity, Power, and Safety Basics.