Bumboseat - D4E1 - 3D CAD IV - Parametrisch Ontwerp

Parametric modeling means that with the help of pre-specified formulas, a given object with unique dimensions can be adjusted according to the new data. Applied to the Bumboseat; The basic tub can vary in length, width and height dimensions depending on the manufacturer or on the target (swing seat or bicycle seat) and the components such as cushions, tubes etc. are adapted to these basic dimensions.

The sizes, which are used , are indicated on the figures below. You can also find the minimum and maximum values.

The three main dimensions are described as height, depth and width.

Height: 150-250 mm

Depth: 280 - 400 mm

Width: 200 - 300 mm

Extra sizes

There are also the depth of the back and the height of the hole, the thickness of the table, diameter of the rod and diameter of the hole, and the width of the strip.

Depth back: 60 - 100 mm

Hole height: 120 - 200 mm

Thickness table: 5 - 10 mm

Diameter rod: 15 - 25 mm

Diameter hole: 8 - 12 mm

Width of the strip: 18 - 30 mm

To adjust the sizes, we open the assembly of the Bumboseat. Once this file has been opened, the keys combination 'Ctrl + E' is entered. After this key combination, all sizes that can be adjusted are visible. Which size is used where is listed below.

Throughout the assignment we made different versions of the bumboseat. This always with a different kind of cushion. Via the next 2 options you get more information about each step in this process. You will also find the specific data for that version.

DIY version

The first bumboseat was made in 2010, during Howest's DesignForEveryoneProject. Use was made of DIY materials, such as mousse, fabric ... For the basic piece, the rocking chair, a standard model was chosen. This also contains the main dimensions of the assembly. From here all other components are controlled via the parametric links.

With this DIY version we chose pillows with a cover. In the next part you can find, how to adjust the sizes, find templates ... We also chose in the DIY version for blocks, to stick the bar with the table. We can also replace these by folding the tube (see explanation of parts).

Template pillows

After adjusting the dimensions (see before) to the desired dimensions, the templates for the cushions can be made visible.

The left column of the program lists all the parts that are in the assembly. For the name of the parts there is a box with a red check mark if they are visible. If not, they are invisible. To view the template for your pillows, place it there. For possible clarity, check the other parts.

On the templates of the cushions we see a suggested cutting line and the stitching line.

Advanced version

In the advanced version we chose to replace the cushions from the DIY version with a more sustainable variant, namely EVA foam.

EVA is a soft, flexible but very tough, UV and weather resistant, insulating, lightweight and wear-resistant material. EVA is suitable for indoor and outdoor applications. Due to the many properties, the material is used in various sectors. EVA is used, among other things, in laminating agents, child seats (YEPP), shoe soles (Crocs), etc. The blocks were also replaced by the folding of the rod.

Template pillows

After adjusting the dimensions (see before) to the desired dimensions, the templates for the cushions can be made visible.

The left column of the program lists all the parts that are in the assembly. For the name of the parts there is a box with a red check mark if they are visible. If not, they are invisible. To view the template for your pillows, place it there. For possible clarity, check the other parts.

Because we chose EVA foam, covers for the cushions are not necessary. We can cut the cushions to the desired size using a laser cutter.

Because the Bumboseat is a parametric model, this means that most sizes are linked to each other. If we measure the child seat and enter these basic dimensions (B, H and D) in Siemens NX, all parts will be adjusted accordingly.

To obtain these sizes, we have to make technical drawings of the desired parts, so that we can make the parts on the basis of this. We want to have a certain part, for example, let laser cabins. Then a pdf of the 'drawing' (= technical drawing) must be printed. This PDF can then be read into Illustrator and removed from unnecessary lines. With this you can go to a fablab or other organization where they can laser cages and have your part lasered.

Chair

The basic part of the bumboseat is the chair. Here we get the main sizes, which are linked to all other sizes of the design. The rocking chair we chose is a standard model that can be found in toy / garden shops. For example https: //www.dreamland.be/e/nl/dl/124063-204-littl ... You can also replace it with a bicycle seat. All hard bucket-shaped high chairs can be used.

Pillows

The cushions are the second most important part of the bumboseat. They ensure that the baby can sit comfortably. There are various ways to make the cushions. Either DIY or via advanced techniques. See step 3.

Plank

The shelf can be used as a table or as a border (to put a child down). The board can be made of various sheet materials, such as plywood, mdf, plexiglass ... to make this plank custom, we can use a laser cutter or sawing machine.

Rod

The bar is used to attach the shelf at a certain height. For this we can use a standard tube with mousse around, we find back in ventilation systems, sanitary ... The sizes we can re-read from the assembly, to keep the rod in place, we use either blocks or we fold the tube away, so that it follows the contour of the shell. This way it stays in place.

Cubes

The cubes were used in the original design to position the bar with the table. The blocks can be made in wood or plastic. By providing the necessary holes and bevels, it fits behind the edge of the shell. To limit the number of parts, the blocks can be omitted. By folding the rod, according to the shape of the shell, these are no longer necessary.

Ribbons

In the design of the bumboseat we see 3 ribbons. These are made with fabric of choice. We sew this according to the pattern that we find in the assembly. (Need to hang a board on the bar).