This project focuses on designing and building an outdoor playset for a two-year-old with sensory-seeking behavior. The family says he is very active and loves to climb, swing, and explore textures.
The goal for this project is to create a weather-resistant playset and allow this child to be as active as possible. The family left most design decisions to us, but they have requested that the playset include a climbing wall, swings, texture wall, tether ball, basketball hoop, and dinosaurs.
Meeting with the family allowed us to figure out what they specifically wanted for the final outcome. The following bullets summarize their requests:
Additionally, we found a handbook outlining safety measures that must be taken when building playgrounds (Public Playground Safety Handbook). A few of the most relevant constraints are listed below:
Playsets are expensive. Looking to the possibility of buying something used and modifying to meet the needs of the child. New playsets tend to range from $1500 to $2500.
This is a sketch of the overall structure in estimating the amount of space we have to work with. It is extremely similar to a typical playhouse layout and helps us imagine where additional structures (climbing wall, swing, slide, etc.) could go.
Needs to accommodate Noah (and potentially parent). Building a “tree fort” allows for a natural shade and easy access for parent. This gives us some flexibility if we cannot buy a playset. Main downside is there needs to be a sturdy tree to build around. Structure is anchored to ground, not tree. What kid doesn’t like a tree fort!
This is trying to include all the family’s design requests while being safe and following playground safety guidelines. The swings would be attached via an adjustable chain mount so the height could be changed as the kid grows. It may also detach in case of inclement weather.
We selected concept design 3 because it was best for safety and meeting the family’s requests. Design 1 did not have a tether ball. The family sent us a picture of their backyard after we had finished each concept, and they do not have a tree, so design 2 would not work.
Our selected design will primarily resemble a standard playground but with modifications and requests from the family, including a climbing wall, busy board, basketball hoop, and tether ball (which is separate from the overall structure). The child will be able to climb the rock wall onto the deck of the central structure. Next to the rock wall is a landing platform to mount/dismount monkey bars. Opposite both of these structures is an opening to a slide. There will be a railing around the central structure to ensure he cannot jump or fall. Attached to one side is a frame where two swings will be mounted.
From the top down, we decided that this would be the placement for how the design would look. With the space of 15 by 20 feet, we would use about 6 by 7.5 feet for the main body of the playset, and this would leave us room to incorporate the elements we wanted to include. On both sides of the main body, there would also be a clearance of about 2.5’.
The first thing we wanted to include were lots of different ways to climb on things. From our first meeting with the family, it was immediately evident that Noah enjoys climbing on just about everything, so climbing was a large focus on what we were doing here. The family specified that they wanted a climbing wall. This wall would be a 5.5’ long wall that would reach the landing of the platform with about a 45 degree angle slant. By some basic trigonometry this would dimension the wall to be a board by about 5.7’ by 5.5’.
For added fun, we also thought to include monkey bars with a landing platform that has a ladder. This would all be for included climbable surfaces for Noah to climb. Since he is 2.5 years old and about 3’ tall, we thought to make the monkey bars about 7’ tall, so he might have room to grow with them. If he were to fully grow to a 5’10” height, the bars would still be roughly a foot above his head. This monkey bar height is not set in stone, however, as we are waiting to hear back from the mother as to whether or not she believes this height to be safe. It can be easily changed in our design. As seen in the image, each rung would be 2′ wide and made of 2″ dowels.
The busy board is another element specified by the family as something they wanted. They wanted to include a board with many textures and motions to interact with, as the family was looking for an interactive way for Noah to develop his motor functions. Overall, the board would be 6’ long and would fully cover the back width of the playset. It would only reach about 4’ to the last element, as not to include anything Noah wouldn’t be able to reach, as that would defeat the purpose of the board.
We also wanted to include a slide. This item would be bought and would be about 4’ tall.
We also included the addition of a post for a swing set on the playset. The post would be about 7.5’ long to double the entire length of the playset and leave room for two swings. This would allow for both Noah and a friend or a parent to use the swings together. The swings would be standard chain belt swings that can be bought at a place like Home Depot or most hardware stores. The chains would be on adjustable attachments so they could be adjusted with height as Noah grows.
In later emails, the family also asked for tetherball. This would be put at one end of the playset where it wouldn’t interfere with any of the larger structure of the playset.
Overall, the platform would be 4’ off the ground and supported on 2x4x10 wooden posts.
To make sure that the swing set portion of the playset is safe for Noah, we analyzed it is using SolidWorks simulation. What we did was make the points of attachment for two swings at equal spacing for the manufacturer and then place those swings one foot apart. We then placed a point load equal to one half of one of our team members at each point, simulated the equal loading that the mounting point would take on the swing. The material chosen for this simulation was pine.
The results from this simulation are shown in the images attached. While they look bad, the results for the displacement say we will get a max deflection of 1 millimeter and have a safety factor of 13 on a structure that should have a 2-safety factor. These results tell us that Noah will be able to safely swing without his mom worrying about a 15-pound piece of wood breaking and making Noah fall, then fall on him and injure him.
While researching building materials, we discovered an already-assembled playground that was under $1000. Upon seeing this, we were curious about what ours would cost if it were built from scratch, which is the original intention.
If we were to purchase a pre-made playset, the only components we would have to build are the busy board sections. We would also switch out the climbing holds for dinosaur models we found separately.
The final total between pre-made and custom-built was much closer than expected, where the custom version is $168.08 more.
To make sure that the Monkey bars on the playset are safe for Noah, we analyzed it is using SolidWorks simulation. What we did is take the rung portion of the monkey bars, fixed it at both ends and applied a distributed load of one of are group members weight on it. This ensured that it would be safe enough for Noah and would not break under his weight as he grows up. The material chosen for this simulation was pine.
The results from this simulation are shown in the images attached. While they look bad, the results for the displacement say we will get a max deflection of 0.19 millimeter and have a safety factor of 13 on a structure that should have a 2-safety factor. These results ensure that the monkey bars will be sturdy and strong for years to come.
After our cost analysis and determining where our time would be best invested, we decided to purchase a playset and then add requested modifications. (Also, the family did not ask for anything extremely custom.)
We began the fabrication process by sorting all the pieces of the playset. Throughout assembly, we tested various stages of the playset to ensure it would be safe for multiple people at once.
As mentioned previously, we tested the structural integrity of the playset at different construction phases. This included hanging, standing, jumping, sliding, and swinging from different support points. In some cases we used two people in order to ensure an adult could safely access different areas of the play set.
Reflection of team:
As a team, we learned to work together and deliver a good product to the client. To do this, we had to learn to effectively communicate with each other and delegate work to one another.
Reflection of project:
This project taught us to overcome obstacles similar to those seen in industry. Initially, we had a complex and grand design that would have been our ultimate goal, but due to time and budget constraints we had to rethink our design. This is often the case when designing to engineering applications. We had meaningful discussions about possible solutions that would still fill our criteria.
