Team:Sheffield/Model
First modelling insight
OPENLUX was designed using a 3D CAD model in Fusion 360. Every part of the device is modelled and tested before it is created. This allowed redesigns and troubleshooting in software saving the team money and time. Using the model, the size of components could be determined without spending unnecessary time measuring, creating and testing components. The components are designed, modelled and then tested in software. Various major design changes happened using our 3D model. Our initial design used two motors in total as seen in Figure 1.
The benefit of only two motors in the above design reduces the overall size and cost of the device. It simplifies the electronics and movement code. The model, however, showed us that the belts used to move the device would get in the way of the sensor and light source. The bottom belt restricted the room available for the sensor mount and the top belt would pass in between the light source and sensor blocking it.
The revised design uses four motors. Two for the top layer, tow for the bottom. Figure 2 shows the current design.
Second modelling insight
The device uses physical end stops to stop the motors turning to far and to provide a way for calibrating the platforms' positions. If they were to turn unhindered, the device would break itself. The initial design used external end stops that extended out of the base of the device and used the sensor skeleton as an end stop. The moving platform would then push against the end stop after travelling a specific distance. This was tested in software by animating the joints and sliding the plate as far as it can go. Using this model we determined this method would disturb the sensor and add complexity. The new iteration added end stops under the rails directly stopping the bearing.
