Bridge by toothpicks
How to design a normal bridge by toothpicks
The designing of a normal bridge with the use of toothpicks necessitates patience with tedious handling. Designing of a normal bridge requires conceptualization on the actual shape of the completed bridge. The best curves of the bridge will depend on the applied forces during the design with the point force in the middle distributing force. When designing a normal bridge by using toothpicks, lay the toothpick on the specified work surface considering the wide end directly facing the upfront. Spreading of glue follows along the toothpick one side edge. Pressing another toothpick with the narrow end directly facing upfront against the glue and pressing firmly for seconds constitutes the next step. This is the creation of one plank with an equal width for the normal bridge. This should have repetition about 200 times for the medium-sized bridge. This enables the creation of 200 planks.
Setting of the plank follows on the work surface. This is with spreading of glue at one end over one-third of the top. Pressing of another plank follows to join the planks for making the required longer piece on the glue top. To lengthen, spreading the glue follows on the second plank top. The repetition enables the joining of the other 30 planks together. The above steps repeatedly set three times to create four plank lengths for the normal bridge. The two lengths created of planks set side by side with a separation through placement of two toothpicks amid at each end of the lengths.
Spreading of the glue follows on the ends of the toothpicks separating onto the length ends. Spread the glue inside the two lengths edges on the centre. Press the glued edges centre together to enable the middle of the lengths bond together. Holding it firmly for 30 seconds is significant for the formation of the bridge underside. The remaining two toothpick lengths lay side by side. Arrange the toothpicks across at one end of the two lengths. Repetition follows with an approximation of 1-inch interval.
Apply the glue to the separator toothpicks end and make a firm pressing in place across the normal bridge constructed. At the length ends, dubbing of glue follows. Bend the constructed bridge placing it over the first two lengths set at the top. Apply firmness while pressing to join the bridge top to bottom at the respective edge ends. Place the toothpicks amid the set bottom and the bridge top to enable holding of the structure properly in place.
What did you learn about this design?
I learnt that the design depends to enable a balance on each respective side of the bridge on four basic catenaries arches for weight transfer. This facilitates the working in tandem nature compared to the regular truss having struts connecting the arches at the upper to the ones in the lower region. I also learnt that the applicable obscure function of trigonometry has a hyperbolic cosine. For normalizing the functions, a specified part of the given curve is applicable to get the required height with magnification to the necessary size following. This necessitates a little application of algebra. Essentially, the upper arch and the lower arch of the normal bridge have the same initial function of the curve.
I also learnt that the modern engineering and computing techniques applicable in normal bridge designing necessitates subtle pinning of the arches. This enables the connection of additional pieces involving a 3D framework assembling. The sample of a normal bridge designed:
