This article discusses STEM (Science, Technology, Engineering and Mathematics) education as an initiative from various countries around the world to address young people's lack of interest in careers in Science, Mathematics, Technology and Engineering. Understanding that STEM education must explore two or more of STEM themes, using transdisciplinarity, engaging the student in activities with this approach, we present the studies of an activity proposal integrating Engineering, Technology and Mathematics with the objective of learning Mathematics. In this activity students work with situations involving robotics and, for solution, use robotic arm simulators, developed in GeoGebra software, that simplify the real environment in which the robotic arm manipulates an object positioned in the plane, taking to organize strategies by identifying and applying mathematics, such as trigonometry with right triangle, trigonometric identities, inverse trigonometric functions, to solve the problem. An experiment was conducted to validate the simulators with undergraduate mathematics students from Universidade Luterana do Brasil (ULBRA) in the city of Canoas in Rio Grande do Sul. The results indicate that it is possible to integrate the STEM areas with the developed simulators, being indicated for activities with high school students (10th or 11th grade).