Preliminary R&D Lab 1: Basic Functions
Programming Basics: A sample AEV was created and tested to run different, basic programs to both ensure everything worked and to allow the user to practice with the different programming commands.
Preliminary R&D Lab 2: Reflective Sensors
The reflective sensors attached to the lever arm serve to measure the distance that the AEV has traveled. The sensors use light reflecting off of the silver tape on the wheel to count the rotations that the wheel has made. The sensors are separated so that the readings from the tape are more accurate.
Preliminary R&D Lab 3: AEV Concept Design
Initial Group Concept Design:
Description: The goal of the initial group concept sketch was to balance a minimalistic approach while also creating an efficient vehicle. Aside from a basic structure (the base board, two wings), the only additional part is a custom hood on the front of the vehicle. The hood has a very simple design with its purpose to help the vehicle be more aerodynamic. The front of the vehicle also contains a part to attach the load that will need to be picked up on one end of the track during testing. Additionally, the wings and motors have been moved to the middle of the vehicle, since the AEV will be moving in forwards and reverse, placing the blades in the middle won’t allow more work to be done in one direction compared to the other.
Estimated Weight: The minimalist approach makes its weight very light compared to the sample AEV
Cost: Arduino, 2 wheels, AEV suspension, Battery Pack, 2 count sensors, 2 electric motors, 2 propellers, 2 count sensor connectors (Necessary for every AEV, totaling $144.88), Rectangular Board, 2 Trapezoid, cone tip (must be self made), tools and clamps: Estimated Total of $175
Individual Concept Designs:
Logan Bowen –
Description: This design was created with a balance of weight in mind. All of the heavier objects, the AEV circuit board, the battery, and the propellers are all located near the middle of the AEV itself. This would prevent the device from becoming unbalanced as it sped ahead. It also took inspiration from cool sci-fi spaceship ideas. A slim body with large, angled wings in the front and back would help it be aerodynamic and keep access weight off. Overall, it is a design that was deemed to have practical ideas that would be implemented in the first, drafted idea.
Estimated Weight: The weight would be slightly higher than that of the sample AEV because of the additional parts on the AEV including wings.
Cost: Arduino, 2 wheels, AEV suspension, Battery Pack, 2 count sensors, 2 electric motors, 2 propellers, 2 count sensor connectors (Necessary for every AEV, totaling $144.88), 2 trapezoids, 2 triangular boards (must be self made), cone tip (must be self made), tools and clamps: Estimated Total of $190
Eric Baron –
Description: This design was made to be as simple as possible, to cut down on any extra weight, while still being able to get the job done. This concept produces a very simple AEV that will get the job done without many bells and whistles. It is a blank canvas that can be added on to if any more parts are deemed to help the AEV more than it hurts the overall performance.
Estimated Weight: The design cut down to the bare minimum of what an AEV needs to be allowing it to be extremely light compared to the sample AEV.
Cost: Arduino, 2 wheels, AEV suspension, Battery Pack, 2 count sensors, 2 electric motors, 2 propellers, 2 count sensor connectors (Necessary for every AEV, totaling $144.88), 2 rectangular boards, tools and clamps: Estimated Total of $160
Alec Pellicciotti –
Description: The goal of this design was to try and make the AEV as aerodynamic as possible to maximize efficiency and get the most out of the motors. The fin on the front of the design and custom curved hood encompassing most of the AEV were included to accomplish this goal. However, the addition of the fin to the front of the design does not allow any room for a device to connect to the load that must be collected at one end of the track during testing.
Estimated Weight: The design is in comparable weight to that of the sample AEV.
Cost: Arduino, 2 wheels, AEV suspension, Battery Pack, 2 count sensors, 2 electric motors, 2 propellers, 2 count sensor connectors (Necessary for every AEV, totaling $144.88), many self made parts to create aerodynamic design, tools and clamps: Estimate total of $144.88 + self made parts = Depends on how much self made parts cost.
Cedrik Seebohm –
Description: The idea behind this design was the structural integrity and safety of the vehicle. The Arduino and battery pack in a completely secure part of the AEV and the arm attaching the AEV is given extra support. The compactness sturdiness of the vehicle will prevent major damage in the event of any accidents during testing. The magnet is held 4” away from the Arduino, doubling the requirements.
Estimated Weight: The design is slightly heavier that that of the AEV as it prioritizes safety over lightness.
Cost: Arduino, 2 wheels, AEV suspension, Battery Pack, 2 count sensors, 2 electric motors, 2 propellers, 2 count sensor connectors (Necessary for every AEV, totaling $144.88), 5 rectangular boards, trapezoid, cone tip (must be self made), tools and clamps: Estimated Total of $185
Preliminary R&D Lab 4: Design Analysis Tool
Phase 1 of the test run is the initial reverse command programmed so the AEV would initially move forward. Phase 2 represents the acceleration of all motors from 0% power to 25% power in 3 seconds. This acceleration is accurately depicted below in Figure 6, and because the motors are just accelerating but not moving there was no total distance traveled by the AEV, as shown in Figure 7 below. Phase 3 shows the AEV moving at 25% power for 1 second, which is programmed as a combination of the motorSpeed and goFor commands. According to Figure 7, the AEV traveled only about 0.03 meters during this period. Phase 4 is the reduction of power in all motors from 25% to 20%, which is accurately reflected in both Figure 6 and 7 as a sharp drop in power on the y-axis. Phase 5 represents the AEV moving at 20% power for 2 seconds, which again only travels about 0.03 meters according to Figure 7. The AEV then brakes and reverses all motors, which requires an input of power over an extremely short amount of time, seen in Phase 6 of Figure 6. All the motors in the AEV then function at 25% power over a 2 second span in Phase 7, traveling a significantly greater distance in the reverse direction compared to the forward direction as shown in Figure _ (about 0.33 meters). The brake command is then executed during Phase 8, with the AEV coasting only slightly after the motors break according to Figure 7.
Preliminary Lab 5: Screening and Scoring Matrices
Screening Matrix
Scoring Matrix
The screening and scoring matrix allowed the group to narrow down the AEV designs to move forward with from the six given initial designs to the initial group concept utilizing aerodynamic features as well as the bare minimum design to use during in further testing. These two designs emphasized the features that the group felt were most important in order to create a successful AEV that fit within the given budget and constraints. This importance is reflected in the scoring matrix, where weight was given a 50% weight and aerodynamic attribute was given 20% weight.
Aerodynamically Focused Design:
Aerodynamic Design (Design 1)
Performance Test 1 Design 1 Power Output over Time
The aerodynamic design used the cross base as well as two trapezoids angled down in the center of the base to act as wings with two motors and the large propellers in the push configuration. This design completed the first performance test using 61.485 J in a time of 16.2 seconds. While this design uses a fairly large amount of power, the aerodynamic design completed the first performance test faster than the lightweight design, shown below.
Lightweight, Minimal Design:
Lightweight Design (Design 2)
Performance Test 1 Design 2 Power Output over Time
The lightweight design consisted of only the cross base and a single motor with a large propeller in the push configuration. This design completed the first performance test using 55.356 J in 19.2 seconds. The lightweight design is not only beneficial in being more efficient by requiring less energy to displace the AEV, the fact that less parts are included in the design decreases the initial budget of materials to leave a greater budget for time and energy costs. However, the time for design 2 to complete the first performance test was greater than the time taken for design 1. Because time is more valuable than energy, it is more likely that design 2 may result in a higher budget when the AEV runs the track in its entirety. Additionally, with the addition of carrying a load, the AEV would move significantly slower with a greater weight attached and only one motor, adding greatly to the time budget.
Final Design:
Aerodynamically Focused Design:
Aerodynamic Design (Design 1)
Final Performance Test Design 1 Power Output over Time
Ultimately design 1 was utilized as the final design to use for the remainder of the performance tests. Because design 1 completed the tasks accomplished in both performance tests 1 and 2, which included traveling to and stopping at the gate, passing through the gate and stopping at the loading dock to pick up the load, and leaving the loading dock, much faster than design 2 it was most cost efficient to move forward with design 1. The cost per second of time is much more expensive than the cost per joule of energy used on the track, and since design 1 is more efficient in time at the cost of only using slightly more energy would maximize the savings of the budget.
The final performance test was completed using an average of 208.427 J in an average of 52.95 seconds between the two best runs completed. The final cost budget, including initial design cost, energy and time costs bearing the accuracy penalty, was successfully under budget at an average of $595,379.48.
AEV Final Run:
AEV beginning the performance test and leaving the starting dock
AEV successfully stopping at the gate (first time)
AEV picking up the lad in the loading dock
AEV returning to and stopping at the gate with the load