Pedal Power

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Pedal Power for the Occupy Movement

To support the self-sufficiency of Occupy member sites, the Pedal Power group aims to facilitate the low-cost construction and effective usage of pedal-powered electrical generators and related technologies.

The goal for this design was low cost, with most materials sourced from Home Despot and/or local hardware stores. Can be built relatively easily by anyone with access to drill press and basic tools. Circuitry includes voltage regulator ($1.50 from digikey), a few capacitors/resistors, and a diode.


10/28/12:  UPDATE IN PROGRESS Also check out:
pedalpower2thepeople.pbworks.com and video


Contact Info

Group email: pedalpower@mit.edu

List admin: moallem@mit.edu

(** PLEASE DO NOT RELOCATE OR RADICALLY MODIFY THIS PAGE WITHOUT FIRST CONTACTING LIST ADMIN. KTHX **)

Parts/Materials List

"A-frame" bicycle stand


Rear Legs:  

TWO (2) x 20" lengths of 1" x 1" (cross-section) rectangular steel tubing


Rear-Cross piece:

TWO (2) x 12" lengths of 1" x 1" rectangular steel tubing 

  • Alternatively, can use single piece of 2" x 1" rectangular steel tubing


Front Legs:

TWO (2) x  20" lengths of 1-inch angle steel  


Front-Cross piece:

ONE (1) x 16" length of 1" x 1" rectangular steel tubing 

  • For extra stability, lengthen FRONT-CROSS piece to between 20"-30", and add rubber feet at either end


Front-Back-Cross pieces:

TWO (2) x 20" lengths of flat steel bar 


Nuts and Bolts:  

  • Use bolts sized 10mm to 12mm (standard sizes 3/8, 7/16, or 1/2), 'with correspondingly sized nuts, unless otherwise specified.
  • Drill holes to slightly larger diameter than that of traversing bolt.


____________________

Rear-wheel (skewer) supports:

TWO (2) x5"-6" long fully-threaded bolts, size 3/4-10 (standard)

  • bolt head type does not matter
  • Alternatively, can use 5"-6" lengths of 3/4-10 threaded rod 

FOUR (4) x 3/4-10 Hex Nuts


TWO (2) x 1/2 in. PVC Sch. 40 Pressure Slip x FIPT Female Adapter 

TWO (2) x Hose clamps  [OPTIONAL]



____________________

Generator and mounting assembly:

What_kind_of_motor_should_I_use?

ONE (1) x 24V DC motor (100 to 350 watt)

ONE (1) x heavy-duty door hinge

ONE (1) x strong L-bracket, at least 3" long on one side

TWO (2) x mounting plates (approx. 5" x 5", either steel or thick aluminum)

ONE (1) x roller bearings (should fit motor shaft perfectly)

ONE (1) x roller: solid aluminum cylinder, 1.25" to 1.5" diameter (Note: Can alternatively use Nylon cylinder with thin aluminum pipe as sheath)


[SPECIFY BRACKETS, FASTENER HARDWARE, AND DISTAL ROLLER SUPPORT!!! ]




____________________

Electronics:

ONE (1) x low-voltage schottky diode


ONE (1) x adjustable positive voltage regulator

Two (2) x aluminum heat sinks

  • Can use scrap aluminum bar or thick sheeting, so long as there is a flat surface for mounting to components
  • IMPORTANT:  Depending on circuit configuration, it may be necessary to connect diode and voltage regulator to separate, non-contacting heat sinks.  (Remember, aluminum conducts electricity!)

Construction

PedalGen_Assem1-1_crop_labeled_small.png

Basic A-frame configuration, depicted without nut/bolt fasteners.


Rear-legs1_labeled_small.png

  • On one face of each rear leg piece, mark distances of 1.5" and 2.5" from bottom edge, centered along the width.  Drill two through-holes, slightly larger than fastening bolt diameter.
  • On perpendicular face of each rear leg piece, mark distances of 4", 16.5", and 18" from bottom edge, centered along the width.  
  • At 4" and 16.5" marks, drill through-holes, slightly larger than bolt diameter.
  • At 18" mark, drill though-hole of approximately 0.75" diameter (to fit size 3/4-10 bolt or threaded rod).

Front-legs1_labeled_small.png

  • If using angle steel, note that hole patterns of the two front legs are mirror images of one another.
  • On one face of each front leg piece, mark distance of 1.5" from bottom edge, centered along the inner-face width.  Drill through-hole slightly larger than fastening bolt diameter.
  • On perpendicular face of each front leg piece, mark distances of 3" and 18" from bottom edge, centered along the inner-face width.  Drill through-holes slightly larger than fastening bolt diameter.



Cross-pieces1_labeled_small.png



Operation