Progress Questions

Exercise 1

  1. In scenario 1, line one the propeller did meet some initial resistance at low starting speeds but after that the scenario seemed to work as designed. The functions executed smoothly and properly without any noticeable failure.

Exercise 2

  1. Progress Report Question: The coding for the Arduino nano could have a limitation with stopping the AEV. When the “brake()” function is used, it stops the motors, but naturally momentum would continue to carry the AEV forward until friction were to stop it. We would need to account for this when coding our final program. We could try to prevent this by actually reversing the motors and running them in the opposite direction until the AEV stops rather than just braking the motors. This would actually ensure a true “break” function rather than the function that is already a part of the program.
  2. Website Deliverables: The wheels that go on the track for the AEV are taped with a reflective material so that the reflectance sensors may work. These sensors emit an infrared light and whenever that light is not reflected, the sensors record it as a “mark.” Thus by knowing how many “marks” per revolution of the wheel there is, distance calculations can be performed, which is the primary function of the reflectance sensors. These distance calculations are imperative to the completion of the MCR as they are the basis on which Arduino commands are executed to tell the AEV how far or to what position to travel.

Exercise 3

  1. Progress Report Questions: Power_vs_Time Plot and Power_vs_Distance Plot – These are the plots from the AEV function that was used to test the MATLAB data extraction program. In the graph of Power vs Time, it is accelerating (increasing power) steadily over the first few seconds, then maintaining a constant power for the next few. This corresponds with the code, so it is logical. At around 8 seconds, the power was dropped down to 0. It is visible in the Power vs Distance graph, however, that the AEV kept moving while at zero power before eventually coming to a stop. This will need to be accounted for in the final coding.

Exercise 4

  1. Progress Report Question: Aspects of each individual design were used in the creation of the final concept. Robbie’s individual design had a wire-frame structure, and came to a point on each end. The wire-frame concept was an attempt at making the AEV as lightweight as possible to make it more efficient. The pointed ends were to ensure that it was aerodynamic on each side. The wire-frame concept was eventually discussed to not be used for the entire AEV, but potentially on parts that may allow for it. The pointed ends will not be featured on the final design, as one side will be more flat to allow for the magnet to be attached and carry the load. Ryley’s design was blimp-like in shape, and had a motor on both the front and back. This was to keep the AEV well-balanced and allow for both forward and reverse mobility. The blimp-like shape did not make it through to the final shape of the design, but the concept of balance was discussed and considered in the final design. Conner’s design involved a pointed end as well, with a lightweight siding to it to help make the vehicle lightweight. This concept was used in designing the final concept, as there will be a thin layer on each side of the AEV, and potentially one pointed end. It also had both motors on one end of the AEV. This concept was used in the final design, as it was determined that one end containing both motors may be best for maximizing the power of the motors. Steve’s design had a very lightweight design. The design intended to be as lightweight as possible and equally balanced. The propellers were also moved to the front/back to get better airflow and movement. The most important concepts that were determined from the brainstorming and discussion of the AEV were using both motors on one end to attempt to maximize power, specifically in the reverse direction, as this will be the direction traveled when carrying the load; a lightweight model, as this was determined to be more important than being aerodynamic; and a balanced AEV, as it was advised to keep balance in mind or else the AEV would not function as intended. These concepts were found through brainstorming by analyzing each design one-by-one and deciding on which aspects of each were most important and useful, and which were not. The final design became a collective product of each individual design.

 

Exercise 5

Ryley

 

 

 

 

 

 

 

 

  • Pros
    • Mobility and aerodynamics
    • Some Balance
  • Cons
    • too much added weight

 

Robbie

 

 

 

 

 

 

 

 

  • Pros
    • Mobile and lightweight
    • Well balanced
    • Aerodynamic
  • Cons
    • Unnecessary features
Conner
  • Pros
    • Aerodynamic
    • Relatively light
    • Powerful motors
  • Cons
    • Lack of mobility
    • Complexity
    • Potential balance concerns

Riley

  •  Pros
    • Mobility
    • Light
  • Cons
    • Lack of aerodynamics

 

Concept Screening

Success Criteria Reference Ryley Robbie Riley Conner
Aerodynamics 0 + + 0 +
Appearance 0 + + 0 +
Weight 0 – – 0 0
Balance 0 + + + +
Mobility 0 + + + –
Net Score 0 4 4 1 2
Continue N Y Y N N

Concept Scoring

Success Criteria (Weighted) Reference Ryley Robbie Riley Conner
Aerodynamics (0.3) 1 5 4 1 4
Appearance (0.0) 1 4 4 1 3
Weight

(0.8)

 2 1 3 2 3
Balance

(0.5)

 2 3 4 3 4
Mobility

(0.6)

 2 4 5 4 3
Score 4.1 6.2 8.6 5.8 7.4
Continue N N Y N Y

The concept screening and scoring spreadsheets allow the evaluation of the features of each concept AEV design. As the purpose of this project is to create the most efficient, successfully performing AEV possible some of the most important criteria for success include the weight, forward and reverse mobility, balance, and aerodynamic features of the AEV.

As Robbie’s design is the most lightweight, balanced, and mobile design and Conner’s design is close behind due its powerful coaxial motors, some of their elements will carry over to the design cycle.

 

 

 

Ohio State Fundamentals of Engineering Program. (n.d.)  Preliminary R&D Lab Manual. [Course documentation]. Retrieved February 7,2019 from carmen.osu.edu