Power Learning - The Pedal Powered Prime Mover in the Classroom

Grade Level

The PPPM can be completely assembled by mechanically-inclined students in grades 9 and above. Younger students will need more supervision, especially when working with power tools.

It is possible to pre-assemble the more complex parts of the PPPM, leaving the students with simple assembly activities. This approach works well if tools are not readily available, time is short, student capabilities are insufficient, or if the focus of the activity is post-assembly use and measurement of the PPPM inputs and outputs.

Subject(s)

Properties of materials, including wood, steel, stainless steel, polyurethane, copper wire, and ball-bearings

Physics, including levers, "gear" ratios, coefficients of friction, work, power, efficiency, torque, measurement techniques, center of mass, balance, Laws of Thermodynamics

Geometry, including diameters and circumferences of circles, tangents, locating the center of a circle, SSS calculations, calculating heights of perpendiculars given lengths of enclosing triangle sides, and an understanding of intersecting line segments and angles as they pivot around the point of intersection.

Electronics, including basic DC circuitry, properties of DC motors and generators, diodes, magnets, electrical resistance, wire sizes and power carrying capabilities, Amps, Volts, Watts, Watt-hours, Joules

There is an opportunity to experiment with different circuit combinations using the online Circuit Builder

Human physiology and power output, including peak vs. sustained output, body temperature regulation, issues with different sizes and shapes of Human bodies, conditioning levels and how they affect power output, pulse rates, breathing rates, Oxygen debt, changes in conditioning with exercise, fatigue

Here is an example of the kinds of experiments that can be performed with a completed PPPM: PPPM Science

Time Required

It takes 8-24 hours to assemble a PPPM, depending on many things, including students' expertise, tools used, and how "finished" the final version needs to be. Painting the unit takes extra time, for example.

Eight one hour sessions with well-executed planning and supervision would result in a unit that could generate measurable electricity. Additional sessions would extend the PPPM to power devices, pump water, or serve as a learning foundation for physiology and energy topics.

Organization is extremely important. All parts must be purchased, all tools must be present, appropriate safety gear must be available, and the organization of the assembly team should be decided before the activity begins.

A completed PPPM may be easily disassembled to any level and subsequently used as the basis for an accelerated course. This approach can avoid "dead spots" caused by more difficult assembly steps, and it can also be used to bypass steps not relevant to the course goals.

Description

Students will assemble a Pedal Powered Prime Mover from plans using commonly available parts. During the process, students will learn the role, function, material, and science behind each part. The completed PPPM will serve to convert Human effort into quantifiable forms of energy, both electrical and mechanical.

Materials

The plans (available through the link at the top left corner of this page) list all materials and tools. Some uncommon tools, such as certain sizes of drill bits, one or more of the required files, and possibly a battery terminal puller, may need to be purchased. These are all inexpensive tools. (Typically less than $10 each.)

Skills Students Will Require

This project is roughly as difficult as assembling a bicycle from parts. There is nothing terribly difficult, but certain steps definitely require more attentuion and skill than others.

In situations where the students' expertise is insufficient to accomplish a step, which will rarely happen, a bicycle shop or a machine shop can be consulted for assistance with that step.

Even if you plan on building a single PPPM, an entire team may be organized to achieve the result. The perfect "assembly" team would have:

1. Simple woodworking experience (drilling, sanding, rough carving.)
2. Simple electronics experience (soldering, use of a multimeter, DC circuit knowledge.)
3. Mechanical assembly experience (drilling holes in metal, bolting things together, screwing water pipe together.)
4. Simple understanding of physiology and related facts, such as common inseam measurements, arm length, and comfortable bicycle riding postures.
5. Esthetic experience (making rough, hand-built items look finished, and of course visually appealing.)

The level of content detail for each of the subjects may be easily adjusted according to grade level or student interest. Virtually every step of the assembly could become the basis for extended material properties or physical science research. There is a "why" behind every part, configuration, and assembly technique.

And imagine the fun of conducting pedal power experiments like this!

In other words, the PPPM construction activity will be a watershed of potential learning.

Finished PPPMs inspire learning independent of the construction process. Consider donating or selling finished units at cost to local NGOs offering energy education or demonstrations. The donation of the device, and the knowledge of how it would be used would be part of the learning.

A complete lesson plan designed for a converted bicycle can be found here.

Order the plans, and plan your Pedal Powered Prime Mover Power Learning class today!