How to calculate the farthest point within a piece?

Fda

I would like to know if there is some kind of Feature Scripti capable of searching the furthest path of a flow of plastic material injected into a part.

(I hope I have explained myself well )

ilya_baran

I think the picture is clear -- mathematically, given a point S, for every point E on the surface, you want to take the shortest path from S to E within the volume and then get the length of the longest of these paths.

This is not a simple computation to do -- we certainly don't have anything that'll compute it exactly.  Off the top of my head, I don't have great approximate suggestions either.  I think you need specialized software for this. 

romeograham

...yep - a Moldflow analysis partner to work directly with Onshape documents!

Fda

ilya_baran dijo:

Creo que la imagen es clara: matemáticamente, dado un punto S, para cada punto E en la superficie, desea tomar el camino más corto de S a E dentro del volumen y luego obtener la longitud del más largo de estos caminos.

Este no es un cálculo simple, ciertamente no tenemos nada que lo calcule exactamente. En la parte superior de mi cabeza, tampoco tengo grandes sugerencias aproximadas. Creo que necesitas un software especializado para esto. 

• I am aware that a "Moldflow" type software would be the most suitable solution.

• Onshape has features that are helpful to calculate quickly:

- The area selected in "mold dividing line"

         (part + channels + spuere bushing)

- The volume of the piece.

- Material's list.

         -> ABS (1.052e-6)

         -> HDPE [High-Density Polyethylene] (9.410e-7)

         -> Polypropylene (9.130e-7)

         -> etc ..

- Draft analysis.

• I don't know when I saw a feature capable of evaluating the farthest point

 

• I thought that with some kind of "Query", "evVertexPoint" could do something like this.

Compared values to count the furthest.

ilya_baran

evDistance can calculate the farthest point in a body from a given one, but it uses Euclidean distance, whereas you need shortest-path distance within the volume.  evVertexPoint just gives to the coordinates of a vertex.

Thinking a little more, if I had to approximate this, I'd probably sample a bunch of points on the surface and interior, connect every pair of points if the line segment between them is contained in the interior of the solid, and then use Dijkstra's algorithm on the resulting graph.

ilya_baran

I think the picture is clear -- mathematically, given a point S, for every point E on the surface, you want to take the shortest path from S to E within the volume and then get the length of the longest of these paths.

This is not a simple computation to do -- we certainly don't have anything that'll compute it exactly.  Off the top of my head, I don't have great approximate suggestions either.  I think you need specialized software for this. 

romeograham

...yep - a Moldflow analysis partner to work directly with Onshape documents!

Fda

ilya_baran dijo:

Creo que la imagen es clara: matemáticamente, dado un punto S, para cada punto E en la superficie, desea tomar el camino más corto de S a E dentro del volumen y luego obtener la longitud del más largo de estos caminos.

Este no es un cálculo simple, ciertamente no tenemos nada que lo calcule exactamente. En la parte superior de mi cabeza, tampoco tengo grandes sugerencias aproximadas. Creo que necesitas un software especializado para esto. 

• I am aware that a "Moldflow" type software would be the most suitable solution.

• Onshape has features that are helpful to calculate quickly:

- The area selected in "mold dividing line"

         (part + channels + spuere bushing)

- The volume of the piece.

- Material's list.

         -> ABS (1.052e-6)

         -> HDPE [High-Density Polyethylene] (9.410e-7)

         -> Polypropylene (9.130e-7)

         -> etc ..

- Draft analysis.

• I don't know when I saw a feature capable of evaluating the farthest point

 

• I thought that with some kind of "Query", "evVertexPoint" could do something like this.

Compared values to count the furthest.

ilya_baran

evDistance can calculate the farthest point in a body from a given one, but it uses Euclidean distance, whereas you need shortest-path distance within the volume.  evVertexPoint just gives to the coordinates of a vertex.

Thinking a little more, if I had to approximate this, I'd probably sample a bunch of points on the surface and interior, connect every pair of points if the line segment between them is contained in the interior of the solid, and then use Dijkstra's algorithm on the resulting graph.