college of engineering white

Project 6: Outdoor Play Structure


(Design Project: Outdoor Play Structure – Team 6 Spring 2024)

This project aims to design a creative and safe kids play structure that promotes outdoor play and physical activity for the child. The design will prioritize safety features, such as sturdy materials, proper installation, and age-appropriate components. In keeping with the child’s peculiar needs, the structure will be comprised of modular sections for easy transportation and feature custom aspects such as hidden interlocking hardware mechanisms as to limit the child’s exposure to potentially unsafe building components and material surfaces. Additionally, taking the parents’ wishes into consideration, the play structure will incorporate elements that stimulate imagination and creativity, encouraging the child to engage in imaginative play. Through this project, we aim to provide a fun and engaging outdoor play experience for the child while ensuring their safety and well being.

(Left to Right) Chaim Roehrs, Andrew Johnson, Robert Lythgoe, Tyler Kinchen, Braxton Baumann

Problem Statement

The client family has requested a playset that can satisfy the child’s desire to climb and to “tunnel”. Tunneling has been described to us as a desire to find small spaces and enclosed areas to relax and feel safe. The child also loves to swing, the color pink, Minnie Mouse, and lights.

The playset must be of a height that the mother has the ability to lift the child off of the top of the playset if necessary, approx. 5.5 ft at the peak. Structurally resilient and strong enough that it can support a 300 lb. Modular and light enough to be moved by the mother. It also must be collapsible/compactable enough to be taken with them when they move later this year. They requested a small rock climbing wall and a rope “ship rigging” net for climbing. As well as a solution for the child’s “tunneling”.

Design Specifications

• 3-year-old child

• height/size of structure to match girls climbing capabilities

• parent needs to be able to reach kid on top of structure

• strive for continued engagement for several future years

• outdoor play apparatus needed • child has sensory issues

• play structure needs to be portable

• components of structure need to be extra safe

(no sharp edges, no chewable material, no choking hazards, etc.)

• child will be under supervision while playing

• child feels comfortable in semi-isolation

• structure needs to be able to hold up to 300lbs

• no rustable materials/components

• parents asking for specific features

(rock-climbing holds, “ship-rigging” climbing nets, etc.)

Background Research

• Because the family requested that the structure be easily transportable, we thought that an assembly system involving some variation of interlocking joints held sturdy with a pin or bolt would allow the family to store or transport the play structure with minimal hassle while also ensuring a rigid and safe frame.

• Our next consideration was the material for the netting and rope materials. Since natural fiber ropes are abrasive, susceptible to being damaged by the elements, and easily frayed or split, we believe that a synthetic fiber such as nylon would be more effective and efficient while also being less irritating to the children that will be using the playset. Many synthetic fibers can feel fairly soft to the touch while being sturdy and resilient which would be ideal for nets where the child or children might lounge or rest. As an additional benefit synthetic ropes are usually fast drying, and they are more resistant to mold or mildew.

• We thought that a possible addition to the playset that could add some enrichment to the playset could be a few panels of fidgets that the children could enjoy during breaks in climbing and exciting play. Possible additions could be small sets of musical items such as a xylophone or drums, interlocking gears, or a wheel full of beads.

• We wanted to add a swing to the frame, and we thought that it would be most reasonable to look to widely produced swing hardware to satisfy this need rather than creating the hardware from scratch. We thought a tire-swing style swing would be especially enjoyable as it would give the children the option to lounge on the swing and enjoy the almost weightless swaying.

• When brainstorming ideas for the structure we had the images provided by the family as well as many that we had seen online that inspired our design decisions. The most important aspects of the play structure were the climbing features and the cool dark hideaways.

Concept Design 1

The image above is a preliminary design of the play structure.

Our preliminary design is one of a wooden A-frame style structure. To satisfy the family’s need to move or reposition the structure we decided on CAMs or “Coffin-Locks” for connecting the A-frame sections. This design will remove the risk of the child disconnecting the structure and remove the risk of pinch-points. The peak of the sections will be hinged to allow the sections to fold and lay flat for storage and transport when the family moves to a new home. Additionally a tent design to satisfy the “tunneling” habits of the child will incorporate eye-bolt and carabiner connections as well as a small hammock or seat suspended inside the tent. The rock climbing wall design options are varied and will depend on the budget for the project.

Concept Design 2

Concept Design 3

Decision Matrix

Overview of Selected Design

The final design will incorporate the layout of Design 1 into the foldable frame style of Design 3.  This will create the mobility the family requested, while maintaining the functionality required by the child’s needsThere will be four climbing sections, a climbing wall using rock climbing holds, a rope rigging wall, a rope ladder, and a standard ladder section. The frame of the climbing area will be held in place after unfolding by coffin locks that can be opened for collapsing the fixture and the closed to lock it together for use by the child. The swing set section of the play area will be made of a metal pole frame that will detach from the frame of the climbing wall and will be able to be disassembled completely to accommodate the relocation of the play area.   

Describe Design Details

The playground fixture will be comprised of two main sections. The first being a climbing area. The second being a swing set fixture. The Climbing area will be made of primarily 2X4 and 2X6 lumber, while the swing set frame will be made of metal poles to facilitate being dismantled for transport. The hardware for these two sections are detailed in the BOM. Details for the individual sections are as follows:

  • Climbing Area
    • One section will be made to imitate an indoor climbing wall with irregularly shaped and static hand and foot holds to build grip strength and coordination. These will be fastened to a sheet of outdoor graded plywood ¾’’ thick using galvanized grade 5 bolts.
    • The second section of the climbing wall will be a section of rope rigging, also referred to as “spider webbing,” to create a climbing fixture with irregular and dynamic footing.
    • The third section will be comprised of a rope ladder to create uniform, but dynamic footing. This will be made of 2X4 rungs and rope rails.
    • The final section of the climbing area will be comprised of a fixed ladder. This will provide a section with regular and static footing. This will be made of 2X4 rungs fixed to 2X4 rails.
  • Climbing Frame
    • The four sections of the climbing area will all be mounted to a single frame comprised of two sections. The frame sections will be made of 2X4 vertical sections attached to two 2X6 horizontal pieces at the top and bottom of the frame sections. The vertical and horizontal components will be used to mount the four sections of the climbing area into a single unit.
    • Hinges will be built into the frame by running two horizontal aluminum poles through holes in the vertical components of the frame. These will act as hinge pins, while the vertical frame components act as the hinge plates. This will facilitate collapsing the climbing fixture to relocate after the initial set up.
    • Two arms made of 2X4 lumber will be used to fix the ends of the “hinge plate” sections of the climbing area. They will be fixed in place at the base of each side of the climbing area and will be locked into place using coffin locks, which can be opened and then closed to lock or unlock the fixture.
  • Swing Set
    • The swing will be a metal ring style swing with three supporting ropes all attached to a swiveling joint that allows rotation. This will allow the swing to spin as well as to swing. The swing will also have a canopy that can be easily removed. This will allow for limited isolation to allow the child to calm down or to simply be alone, yet safely accessible to supervising parties.
    • The frame of the swing set will be made of solid aluminum bar stock to maximize strength, but also to maintain a light weight. The end of the swing set frame will be an A-frame to provide stability. The frame will be held together by bolting the bars into tubes, and will be mounted to the frame of the climbing area with a flanged tube.
  • Tent Space
    • Under the frame of the climbing area will be an area that is made into a tent. The tent will be supported at the ridge by a metal pole made of stainless steel tubing to reduce weight, and will be mounted to the base of the climbing fixture’s hinge pins via ball-loop bungee chords to eliminate sharp objects.
    • The tent will also have lighting available so that children in the tent can turn the lights on or off via a switch, or button.
    • The frame of the tent has been dimensioned such that the tent can be made of a 10X12 foot tarp, which is a standard size tarp. This way the tent structure can be easily replaced in the event of damage occurring through regular use. Replacements can be found at any local hardware store.

Engineering Analysis 1

Engineering Analysis 2

Engineering Analysis 3

CAD Drawings

Document Fabrication Process

Testing Results

Testing yielded uniformly positive results.  To ensure each portion of the play area was safe for use by children each portion was individually used by adult members of the group.  The fixed ladder portion was climbed on to test both the mounts hold on the frame, as well as the rungs themselves to inspect for bending.  During this process, it was determined that additional handholds were needed at the top of the frame to reach the top of the structure.  Two additional handholds were mounted.  These were the same holds that were used on the rock-climbing portion of the playground.  The rock wall portion was similarly tested as the ladder.  Adult members of the group climbed on the rock wall to test the durability of the backing (23/32” thick plywood), as well as the strength of the handholds themselves.  Again, positive results were achieved, with no deformation or damage found.  The rope ladder and rope webbing were tested by laying on them similarly to how one would lay on a hammock.  While there was some settling in the ropes, this was expected and did not create any cause for concern.  The top section of the play area was covered by a sheet of the same plywood used for the backing of the rock wall.  This was done to cover the frame from the rain, as well as to create a shield from pinch points in the frame.  This was tested by being climbed on by the team and the support offered by the frame did not allow for any deformation in the “lid” of the frame. 

Completed Design Photos

Instructions for Safe Use

To ensure the safety of children playing on this playground, always allow them to do so with adult supervision.  Limit the number of children on each section of the playground to one at a time.  Never allow children to stand or sit on the top of the playground.  Never climb over the playground to get to the other side. Instead, climb down, walk around to the other side, and then climb on the other side.  Never run under the playground or stand under another person climbing on the playground to avoid hitting one’s head. 

When using the swing, always do so with adult supervision.  Do not swing excessively, or in such a way as to collide with the supports of the frame of the swing set.  Always make sure that anyone watching is standing clear of the path of the swing to avoid collision with bystanders.  Limit use of the swing to one child at a time.


Project Summary/Reflection

In reflection of the production of the playground several important changes were made.  While the first draft of the playground was a solid and safe plan, it featured over dimensioned supports.  This resulted in excess weight that made mobility an issue.  To reduce weight the cross-sectional area of the supports was reduced by 50%.  Additionally, the surface area of the rock wall was reduced by 25%.  The goal of these changes was to reduce the weight of our heaviest section to roughly 100 lbs.  Another important change that was made was the change of the ladder rungs from 2X4 lumber to 1-3/8” metal tubing.  This greatly reduced the weight of the ladder section.  The bottom horizontal supports of both frame sections were also changed from 2X6 lumber to 2X4 lumber to achieve approximately 50% weight reduction of those components.  To allow the weight to be more easily managed, several of the handholds used on the rock wall were situated such that they could be used as handles when moving the playground.  This feature fitted seamlessly into the design and greatly improved the management of the weight of the playground.   

To improve both the functionality of the swing and the mobility of the playground, it was decided that the swing set would be left detached from the playground entirely.  This allowed the swing to be 6-8 inches higher than it would have been attached to the playground.  It also removed an unsuitable climbing possibility from the playground by not having the crossbeam of the swing set mounted to the side of the climbing wall. 


2024 Spring