Making a Mobile Stand

Geometric shapes and angles describe positions, lines, and the rotational movement between connected objects. A moveable kicking doll mobile stand illustrates basic geometric definitions such as points, line segments, and the different types of angles formed as parts rotate.

Basic geometry concepts

• A point is a single dot on a surface that marks a specific position.
• A line is formed by placing multiple dots together across a surface and connecting them.
• A line segment is a straight connection drawn specifically between two points.

Building the kicking doll stand

Begin by drawing an outline of a kicking figure on paper, making sure the size matches your mobile phone so it can function as a stand. Flip the paper over, shade the entire back darkly with a pencil, turn it back over onto a sheet of sunboard, and trace the outline to transfer it. Cut along the outer line of the transferred shape using a knife, and color the figure and its edges using sketch pens. Cut the leg piece out separately, pierce matching holes through the leg and the body using a skewer, and fasten them together with a push pin so the leg can move freely.

Types of angles

• A zero angle forms when both legs stay pressed together without any opening between them.
• An acute angle measures less than a right angle, reaching values such as 45 degrees or 68 degrees.
• A right angle forms when the moving leg is placed perpendicular to the body at exactly 90 degrees.
• An obtuse angle opens wider than a right angle, measuring values such as 120 degrees or 135 degrees.
• A straight angle occurs when both legs stretch out completely flat in the exact same line.

Angle pairs

Two separate angle measurements can combine to form specific total sums. Complementary angles are pairs of angles that add together to equal exactly 90 degrees, such as one kick at 60 degrees combined with another at 30 degrees. Supplementary angles are two angles that add up to a combined total of 180 degrees.