View source for Advanced Mobility Toy

== Abstract ==
Our goal is to design and construct a bicycle-like vehicle for a child or individual with lower body immobility. We aim to stay as close to a regular bicycle or hand powered device as possible to allow the users to feel less scrutinized when using the vehicle.

== Team members ==

[[File:Group Photo1.jpg|400px]]

Jonus Goldston<br />

Cody Chattin<br />

Jeremiah DeWitt<br />

Mohammed Almajdi<br />

Matt Tinker

== Problem Statement/overview of the need ==
Children with lower body immobility have very limited options regarding effective man powered vehicles. Our goal is to design a vehicle that is easily propelled by a child or individual with little to no leg movement. The most important goal of the device is to provide children with an opportunity to synchronize different brain functions that would otherwise be difficult to do with other toys.

== Design Specifications  ==
The device must be light enough to operate without the assistance of the user’s legs, but must also maintain rigidity and support the weight of the individual. 
Depending on the design, the vehicle may benefit from different lengths; most importantly, wheel position relative to the user’s center of mass.

== Background research ==
Similar products to ours exist, but they all have distinct separation between models for handicap individuals and users with full mobility. Our goal is to create a hybrid that will be usable and enjoyable for users of full mobility and limited mobility. Kids with limited mobility will be able to use the same bicycle type vehicles as their fully mobile friends and may temporarily forget their handicap.

Our frame is inspired by different frame designs we found, while trying to maintain simplicity to cut weight.

== Conceptual Design ==
=== Design Concept 1 ===
* Utilized a gearing design called a ”Reciprocating Rack and Pinion”
* Horizontal movement is converted to rotational movement 
* By rocking their weight back and forth, the user can propel the device
* A gear train will be used in the stages between the RRP system and the axle to improve efficiency and ease of use 
https://www.youtube.com/watch?v=ScB6Wd4r9Jc

=== Design Concept 2 ===
* This design utilizes angular movement of the user’s center of mass  
* By rotating about the front wheel, the normal component of angular acceleration is used to accelerate the vehicle forward
* The vehicle is steered by a free rotating caster wheel mounted under the back seat

=== Design Concept 3 ===
* This design utilized a hand pedal system to power the steered 
* The vehicle is steered by rotating the front column and turning the entire drive system
* This design uses a driving system similar to a bicycle
* This design provides the best path to our goal of having a "normal" device that can be operated by individuals with lower body immobility.

== Evaluate concepts/select candidate  ==
After evaluating the costs and estimating the difficulty in building the finished product in all of the concepts we have decided to fabricate a hand crank tri-cycle. This design presents a moderate difficulty fabrication process, but has the most simple driving mechanism. The majority of the difficulty in the build is in pure fabrication, which is easier to overcome as opposed to a tedious or inefficient powering system. The build should be relatively cheap as we can salvage most of the parts from scrap steel in the shop and old bicycles. The drive system will likely come straight off of an old bicycle, but it will have to be modified to fit our specifications. Our main goal with the hand cranked vehicle will be to keep a high efficiency and to make the vehicle usable for a variety of children, including those with lower body immobilities. The bike will accommodate needs of these children while maintaining a "fun" image and enjoyable use.

== Detailed Design ==
Our design includes a simple three wheel system. The frame will be constructed of simple, cheap steel tubing. The vehicle will use a chain driven power system, similar to a bicycle, that is cranked or pedaled by the user's hands. The vehicle in total will be 6 feet in length and approximately 24 inches in width. 
=== Description of selected design  ===
When designing the look of our vehicle, we tried to balance the design around 3 main points; keeping the vehicle efficient, inexpensive, and fun. We didn't want the vehicle to look like a modified wheelchair. That is where the long slender look comes into play. The pedaling system will use pedals that are fixed in the same angular position to allow the individual to use more body momentum to power the device.

=== Detailed description of selected design ===
=== Analysis ===

==== Engineering analysis 1 ====
Weight Analysis
* The frame will be built out of 1.25" round steel tubing. The tube will have .120" wall thickness. 
* Approximately 16 feet of tubing will be used resulting in a weight of 23 lbs for the frame. 
* After factoring in weight for wheels, driving system, pedals, and seat the goal weight is to be less than 45 lbs.

==== Engineering analysis 2 ====
Stress Analysis of Frame

[[File:Frame2-Static 1-Results-Displacement2.analysis.jpg|800px]]

==== Engineering analysis 3 ====
Gear ratio/velocity analysis of sprocket/chain system 
* Assumption that a human can generate 1.5 pedal rotations per second 
* Using common bicycle sprocket sets, ratio of wheel rotation to pedal rotation is 2:1
* Tire diameter is approximately 18 inches 
* Max wheel rotation speed becomes 3 rotations per second 
* After converting angular velocity to linear velocity, max speed of vehicle becomes 9.5 miles per hour
[[File:GVanalysis.jpg|400px]]<br />
[[File:IMG_4977.jpg|400px]]

=== CAD Drawings ===
[[File:Full.jpg|800px]]<br />

[[File:FullDrawingPhoto.JPG|800px]]

=== Bill of Materials ===
qty, item, description, source, part number, price

{| class="wikitable"
|-
! Item !! Quantity !! Description !! Source !! Part Number !! Price
|-
| Rear Wheels || 2 || Supports/allows movement for back half of vehicle || Amazon || Example || $63.78
|-
| Front Wheels || 1 || Supports/allows movement for front half of vehicle || Amazon || Example || $28.53
|-
| Crank Assembly || 1 || Transfers power to wheels || Amazon || Example || $55.95
|-
| Steel Tubing || 16" || Used to build frame of vehicle || Amazon || Example || $84.35
|-
| Bike Chain || 1 || Used to power vehicle || Amazon || Example || $7.41
|-
| Seat || 1 || Provides support/safety for user || Amazon  ||  || $35.99
|-}

=== Assembly Instructions ===
No assembly required.  The product comes fully assembled.

===Fabrication Process===
[[File:BIKES.jpg|200px]]                                                                             

'''Initial Goodwill Purchase'''

 [[File:PARTS.jpg|200px]]
                                            
'''Rotating Parts Before Finishing'''

[[File:CLEANPARTS.jpg|200px]]

'''Cleaned\Finished Rotating Parts'''

[[File:FRAME1.jpg|200px]]

'''Base Frame Assembly'''

[[File:CAP.jpg|200px]]

'''Custom Caps to Hold Axles'''

[[File:FORK.HOLDER.jpg|200px]]

'''Fork Holder\ Turning Mechanism Installation'''

[[File:PCVHEAT.jpg|200px]]

'''Heating of 4" PVC Pipe to form seat'''

[[File:SEAT!.jpg|200px]]

'''Molded PVC seat'''

[[File:ROTATINGASSEMBLY.jpg|200px]]

'''Fabrication of Crank Assembly'''

[[File:WHEELFRAME.jpg|200px]]

'''Frame with Wheels Installed'''

[[File:FRAMEPAINT.jpg|200px]]

'''Painted Frame'''

[[File:SEATPAINT.jpg|200px]]

'''Rhino Lined PVC Seat'''

=== Testing and implementation===
Trike supports 245 pounds at the location of the seat safely.  The chain and sprocket able to withstand the force needed to propel the 245 pounds on the trike.  the bike will be delivered to Dr. Canfield for evaluation.

=== Photos of Completed design ===
[[File:FINAL.jpg|400px]]

'''Final Product'''

== Instructions for safe use ==
Place the child in the seat and place his\her feet on the foot-pegs attached to the frame. For safe use, always wear a helmet and other protective gear.  never ride the trike on steep grades or slippery surfaces.  Never ride on a surface other that concrete, gravel, or dirt.
Do not use the device unless supervised by an adult that has been fully understood the safe use of this product.

== Project Summary, Reflection ==
This project has been a great opportunity to challenge ourselves not only in engineering design but, fabrication methods and processes as well.  This project challenged us to make a fun toy that children with lower body immobility can feel more normal in.  Our design focused on making the product feel more like a toy and less like a wheelchair to the user.  It also helped us build team building skills giving everybody a part to do in the project and making it all come together in the end.  Overall, the project went well with some minor design changes during the fabrication process to help with weight and overall manufacturability of the design.  By the end of the project we designed, fabricated and delivered a fun toy for under $50 dollars in total parts.