Introduction: MSPF - the Play Station SF

About the project:

The Play Station SF was designed and constructed by a group of friends who got together with the goal to create something fun for the 2016 Market Street Prototyping Festival. Inspired by cities around the world that provide free public exercise equipment on the sidewalks, we asked ourselves, “What if we created a free and accessible way to stay healthy and active for anyone passing along Market Street or those just waiting for the bus?”

The overarching theme of our prototype was high impact at low cost. We wanted to create something that anyone (DIY-ers, urban prototypers, and municipalities with tight budgets) could easily make without skimping on quality and impact. We used recycled parts and reclaimed materials (i.e. found in dumpsters) whenever possible. Everything else was commonly available standard construction material which are relatively affordable.

If you have a limited budget like most citizen groups and are looking for a broke a$s guide to urban prototyping (e.g., the lighter, quicker, and cheaper method of transforming public spaces), this Instructable is for you.

Step 1: Materials

Shade structure and flooring

  • 3x rolls of EcoRug Green Outdoor area rug (6’x8’, from Lowe's) (at most ½” thick for ADA compliance and carpet tape)
  • 1” metal EMT conduit tubing (from HomeDepot or Lowe's), cut to these lengths:
    • 4x 10’ lengths
    • 4x 8’ lengths
    • 8x 2½’ lengths
  • 8x Canopy fittings (1”, flat roof, center-type from
  • Canopy fabric - zip ties, tape, and cord (ladder or step stool)
  • 4x 24”+ bicycle wheels (decoration)

Exercise equipment and interactive bike sculptures

  • 3 exercise bikes found on Craiglist (under $80 each)

Rainmaker sculpture

  • 26” or 29” bicycle wheels (no tire)
  • Bicycle fork matched to above wheel(s)
  • 1" dia. Plastic flex tubing
  • 1" dia. Metal flex conduit
  • Ball bearings (bike shop junk bin)
  • 1¼” x 30” galvanized pipe (threaded ends)
  • 1¼” pipe floor flange
  • 4x screws (matched to floor flange)
  • 18” plywood round

Zoetrope sculptures

  • 20” BMX bicycle wheel (no tire)
  • ¾” x 30” galvanized pipe (threaded ends)
  • ¾” galvanized pipe floor flange
  • ¾” galvanized pipe cap
  • 4x screws (matched to floor flange)
  • 18” plywood round
  • Styrene plastic sheet
  • 2" wide receipt paper rolls
  • Sharpies

LED sculpture

  • Bicycle frame for 29” (or 700C wheels) with functional pedal drive
  • Bicycle wheel matched to above
  • Monkey Light Pro Display System from Monkeylectric (borrowed)
  • ½” x 48” Rebar
  • 9x ½” x 24” Rebar
  • 1½” x 6” Angle Iron


  • Chalkboard easel, chalkboard markers
  • Signage - easel to draw “how far can you go” graphic


  • Spray paint (orange, blue, gold)


  • 2 stools, 2 crates, 1 red chair


  • Bag of supplies: markers, gaffer tape, zip ties, box cutter, velcro tabs
  • Security mechanisms: locks/chains/rope/tarp/cardboard boxes
  • Bike games - printed cards and game accessories basket
  • Sandbags for holding down easel/sign, bike bases, canopy base

Step 2: Design

Here are the overarching guidelines that we followed when designing our prototype:

1) Keep it simple. While it can be easy to over-think these projects, we challenged ourselves to remember the basics of engaging people: how do we appeal to their innate sense of curiosity and playfulness? For us, the equation was simple: Find a trigger, provide a reward. If you turn a wheel or push a lever, you will be rewarded by a sound, or a light show, or something delightfully unexpected.

2) Keep it low-resolution. It’s a prototype that’s supposed to last for three days, and the point of building a prototype is to get feedback first before you spend lots of money to build something permanent just to find out that it doesn’t work. The more money and time you spend on something, you’d likely convince yourself that it’s good when it’s really not. A low-res prototype is supposed to be cheap, testable, rough, rapid, disposable-- all while being a quick way to communicate an idea and a tool to share and generate ideas. A low-res prototype is not precious, something you become attached to, and certainly not a sales pitch (source). For more information about low-res prototyping, see this Process Guide to Design Thinking from the Stanford and this Skeptic’s Guide to Low-Fidelity Prototyping.

3) Seek cheap and recycled materials by visiting community bike organizations (e.g., Bike Kitchen is a great resource in San Francisco) and being on the look-out for furniture that can be found on sidewalks and local dumpsters at the end of the month.

Step 3: Fabrication

  • Design and build rainmaker bike sculpture:
    1. Cut the flex tubing to length to wrap like a tire around a bike wheel.
    2. Put a handful of ball bearings in the tubing and tape it around the wheel. Repeat for a second wheel if desired.
    3. Pre-drill 4 holes in the center of the wood round so that they match the pipe flange, and screw the flange down.
    4. Screw the the long pipe into the flange
    5. Slide bicycle fork into the open end of the pipe
    6. Install the bike wheel in the fork. If you chose to assemble two wheels, then you can flip then to the outside of the fork and install one on each side of it.
  • Design and build zoetrope:
    1. Pre-drill 4 holes in the center of the wood round so that they match the pipe flange, and screw the flange down.
    2. Drill a 3/8" hold in the middle of the pipe cap. Large enough to fit the BMX wheel axel.
    3. Fit the BMX wheel axel into the pipe cap and secure it with the axel nut.
    4. Screw the long pipe into the flange
    5. Screw the pipe cap (with BMX wheel) on the open end of the long pipe.
    6. Cut the styrene plastic (or post board) ~6" tall and long enough to wrap the interior circumference of the wheel with ~1" of overlap at the ends.
    7. Measure the above length and divide by 24. The resulting number is the slot spacing, and is also the width of each frame of animation for the zoetrope. 24 also is the number of frames of animation for this configuration to ensure the animation can be viewed properly. You can decrease the 24 number to make the animation frame wider (which likewise reduces the number of frames).
    8. Use the above resulting number as the interval to measure and cut a series of narrow slots 2" tall all along the length of the styrene. The slots should be parallel to the short side of the styrene, and ~1/2" distance from one edge.
    9. Tape the styrene into the inside perimeter of the BMX wheel, and use staples to secure the ends of the styrene together.
    10. Draw some animations on the receipt paper! Ensure that the frames of animation are the right width as per the slot spacing calculation.
  • Finalize safety on both bike sculptures (braking mechanism, acrylic spoke cover, removable monkeylectric wheel, stable base)
  • Design and build canopy structure:
    We used a modular canopy system that is very simple to configure and fast to assemble. Simply cut commonly available EMT tubing to the desired lengths (using a hacksaw) and insert into the modular fitting available from We chose to have extra fittings as the feet of the canopy so that sandbags could weigh it down. The 2½’ lengths of EMT tubing were added to the ends to appear as overhanging eaves, with junk bicycle wheels zip-tied up as decoration.
  • Design, test, and build canopy overlay (fabric, nylon rope, grommets, zip ties, etc.)
  • Design, print and laminate large (less than 18” x 28”) “How far can you go” map graphic overlay (concentric rings indicate how far you could have bikes at X avg speed in 10 min, half hour, 45 min, etc.), affix velcro tabs to graphic and cafe sign
  • Design, sketch, print and laminate bike games cards (at least 4 games, 3 copies of each).
  • Affix velcro tabs to backs of cards and handlebar area of bikes.

Step 4: Installation

Make sure you find a way to transport your supplies. You’ll need a large van, truck, or a roof rack. Having a few people to help out will make it a lot easier. Zip ties, work gloves, duct tape, and a stepladder are your friends.

  • Affix the astroturf to the sidewalk with double-sided carpet tape and green duct tape.
  • Assemble the canopy structure and attach the fabric before raising. We used 4-way stretch nylon mesh, which worked great because it was flexible and doesn’t fray when cut. We attached it with zip ties. Raise the canopy and secure with sandbags.
  • To set up the installation: choose a place for the exercise bikes. Arrange the bicycle sculptures around them, leaving enough space for wheelchair mobility access and safety.
  • If you want to create the newspaper delivery game, affix an empty window screen to one of the poles with zip ties. We attached a used plastic window box as a receptacle to catch the newspapers.
  • Zip tie used bicycle wheels to the canopy frame for decoration if desired.
  • Prepare rolls of receipt paper, sharpies, and clipboards to allow participants to draw their own zoetrope design.

Step 5: Interaction

Be prepared to walk people through the installation. Lots of people will have questions, such as, “What is this” and “What’s going on." Be ready to give the same answer many times! People are really curious, and they want to know why you’re doing an installation, who’s behind it, and how long it will be there. Some folks are afraid that it is a marketing tactic and will turn down the opportunity to play and interact because they think you are trying to sell them something. Be ready to talk to hundreds of people and invite them in to participate. Many people are curious, but hesitant to enter the installation. Create “soft edges” like we did by placing the zoetropes outside of the astroturf on the sidewalk, so people walking by can quickly take a look without committing. Draw them in.

If folks seem hesitant, you can just jump on the bikes and demonstrating how it works, and then people can see how to use it. We played the “newspaper delivery game” on one of the exercise bikes and every time we hopped on the bike, passersby readily lined up to play too! We had a member of the local business improvement district street team come back daily to play the game, and she got really competitive about improving her skills.

Don’t pre-judge who might or might not be interested in interacting with the installation. We had folks from all walks of life enjoy visiting the Play Station. We had everyone from toddlers to grandmas riding our bikes and spinning the hand-cranked sculptures. We had many visitors ask us why the installation wouldn’t be up for longer, and why it had to be so short. We had visitors remind us that there isn’t sufficient seating for seniors on Market Street. We had visitors tell us that free public workout equipment was a necessity and point across the street at the luxury glass-walled gym on the second floor of the Four Seasons, as people rode spin bikes just like ours while looking down on the hustle and bustle of Market Street. We had bike messengers stop by to chat about cycling and job searching in San Francisco. We had a family of six from Argentina stop by and tell us about their year-long trip across the Americas, while their kids clambered all over the bicycles. We had many unhoused visitors from around Market Street stop by to interact with the sculptures, ask questions, and tell us about their story and where they sleep at night. We had someone on a bike get off their own bike, get on an exercise bike, and play the newspaper delivery game, while wearing a bike helmet.

Lastly, have fun, don’t take yourself too seriously, and remember that there is nothing more humbling than putting your design out on the street and having people directly give you feedback with their actions and words. Take that feedback as a gift, and be thankful for it.