ME360
Product Design
The following work was done mostly in class and was to be submitted as in-class assignments for participation purposes.
Martin Michael Dimo
Disposal Tray Mechanism Design
Motivation: Learn how to design complex motion mechanisms by using software such as Math Illustrations and Solidworks. Use the knowledge from constructing a simple 4-bar linkage to gain intuition on the movement of mechanisms to be a applied to more difficult movement.
Context: Mechanisms are defined as separate parts working together in a system. In engineering, they are used to convert different forms of energy to motion. They come in various forms: gears, pulleys, linkages, and cams. 4-bar linkages are the most simple and have been modeled in the class work section. For this assignment, the same components are used; a crank, a rocker, an extension, and two anchors. However, their motion is much more complicated, as their path is predetermined.
Objectives: Design a trash dispenser that allows for the disposal of trash out of sight of the user. The dispenser must have the following functions:
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Users will deposit their trash on top of the tray
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The tray is taken away automatically
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Trash is disposed into an opening in the back of the container
Given Task: Design a linkage mechanism that moves the tray in a certain way that allows it to clear the body of the container as it travels. The pivot points (i.e. anchors) must be attached to the side of the container, and the location must be determined as well as the length of the crank and rocker. The tray itself will function as the extension of this linkage. The model must work and complete a successful motion study in Solidworks.
Considerations: Several factors will complicate this project. Over-constraining a linkage will cause Solidworks motion analysis not to work properly, and the troubleshooting of such problems is lengthy, to say the least. Thus, meticulousness and accuracy is needed from the inception of the design. Math Illustrations creates a good first proof of concept, but for much more accurate coordinates for my pivot points, I inserted the given dimensions of the example container and created a sketch on top of it in Solidworks. This allowed me to make the perpendicular bisectors much more accurate and resulted in pivot points up to six decimal points of accuracy. After the initial sketch provided the measurements of the linkage bars and the coordinates in relation to the trash container, as mentioned, the individual parts were designed, and then a Solidworks assembly was created. The process will be shown below.
Design Process:
Geometry added to given example dimensions in Math Illustrations
Three-stage motion synthesis using same constraints with greater accuracy in Solidworks
Disposal Tray in idle position
Disposal Tray in end position
Disposal Tray traveling from idle (left) to end (right) position
Evaluation: The final motion of the disposal tray mechanism was tested using a motion analysis in Solidworks. This was only possible after evaluating the motion without motors to first check for redundancies. Given that there are technically two 4-bar linkages working simultaneously (one on each side of the tray), it was a challenge to resolve all joint issues. Once redundancies were resolved by converting mates to concentric and spherical mates, two motors were attached to either side of the container on the crank bar (the shorter link). The simulation then ran, which can be seen below from two different angles.
Isometric View
