For teachers and mentors, examining a must-have step in engineering design workflow.

GUEST COLUMN | by Sandeep Hiremath

STEM-based robotics competitions are beneficial to students in a number of ways, but perhaps the greatest benefit is the exposure to project-based learning in a fun, collaborative, technology-rich environment. While these competitions may not feel like work, the hardware and software design tools students use are actually very often the same tools they’ll employ later in life should they opt for a career in science or engineering. The challenges they encounter throughout the competition process can also mirror the “real world” of engineering, where busy people on tight deadlines are expected to complete their work on-time and on-budget.

Simulation can represent the real environment with something as simple as a sketch of a mechanical design, or as complex as a mathematical model.

One step students (and engineers) often overlook comes relatively early in the project design process. The initial excitement of designing a robot often leads teams to rush to what they believe to be the next step – building it. What they quickly come to realize, however, is that the design often doesn’t capture variables that can lead to operational failure. In a worst case scenario, students find themselves developing multiple iterations of their robot design, spending time and resources they didn’t originally plan for.

Failures are inevitable, however, it is essential to find and fix them to build a more robust robot or system. By incorporating appropriate simulation methods in the project design workflow, teams are better able to spot potential problems in their design and address them at an early stage. Is it an extra step in the design process? Sure, but it’s a step that helps in saving time and money that can be invested in other parts of the project.

Simulation 101

But what is simulation? Simulation is a technique in the design process where a mathematical or visual representation of the real world environment can be easily altered and used so that designers can understand the behavior of a system or robot. More simply put, according to Dr. Richard Gran from Mathematical Analysis Company, simulation answers questions. Simulation can represent the real environment with something as simple as a sketch of a mechanical design, or as complex as a mathematical model.

Organizations like NASA use simulation for space exploration projects like sending a probe to Pluto. When building robots or autonomous systems used to explore the unknown in space, NASA scientists don’t know the scope or makeup of the physical space the system will be navigating. To help in the design and creation of the robot or spacecraft, NASA models how the physical world works, then manipulates it and tests how the robot or system works within the modeled world, in order to simulate what will happen in space. Economists to biologists even use simulation techniques to conduct professional research, with simulation enabling them to make abstract conclusions more concrete.

Simulation tools, such as Simulink from MathWorks, provide a simple block diagram environment that enables model-based designing of systems and simulation features to test these designs. Engineers and scientists across various industries have adopted simulation techniques to help them accelerate the move from concept to creation by troubleshooting their products before committing them to the manufacturing line.

Choosing the Right Fit

Modeling and simulation is incredibly important in engineering because, so often, the description of a system behavior by experimentation might not be feasible due to a number of reasons. These reasons include inaccessible real world conditions; the experiment may be too dangerous or expensive or even too fast or too slow for humans to perceive and test accurately; and the experimental behavior could be obscured by disturbances.

Given the importance of this activity, it’s worth noting there are a number of types of simulation that engineers use that student competition teams will likely find useful. These types of simulation include the following.

• Visual models: In visual models, graphical sketches and computer solid models are used to simulate form and appearance.
• Physical models: By leveraging prototypes, mock-ups and structural models, teams can physically simulate the function of a robot or device. A physical model can be as basic as a mock-up of a device with cardboard, PVC pipes and rubber bands.
• Mathematical/Computational models: There are certain design choices that cannot be validated using only basic visualization or a physical prototype; they need complete representation of the physical world through mathematical models to be able to design the robot or device that provides the desired behavior. Software simulation using algebraic and/or differential equations for computer simulations helps in easily defining these complex mathematical models and then running iterative tests for different design alternatives to validate the design choices.

While mathematical modeling and simulation techniques can help teams obtain results as close as possible to the real world, these simulation techniques are not mutually exclusive. In one application, users could have simulations where the laws of physics are defined using math, but a visual simulator can be used to represent the different objects in the environment and their position and orientation at each instant of time during the simulation. Further, students may find that making software design changes rather than mechanical or physical design changes is simpler and less costly. The point is that there are a number of simulation options that student competition teams can take advantage of to help effectively bring their design to life.

Reaping the Benefits

Simulation not only helps engineers and scientists save time and money, it can also help to improve the quality of the end product. In the engineering world, we often say, “fail fast, fail often, and fail cheap.” Simulation in the context of student competition teams helps ensure that teams will fail at an early enough stage to identify potential design flaws and fix issues along the way. For example, this video from Manthano Christian Academy shows how the school’s robotics team simulated its entry for BEST Robotics 2015 to help the team make informed decisions about their robot during the design phase. Simulation can also save teams money since fixing a minor issue early on is typically much less complex than fixing a major issue closer to competition day. Ultimately, it can ensure teams have a sounder design and operational robot going into the competition.

As teachers and students prepare for their next robotics competition, they should consider incorporating simulation into their project as a de-bugging tool. By engaging in activities like simulation that real engineers, scientists, astronauts and economists use every day, not only will it give teams a potential leg-up against competitors, it will introduce students to tools they’ll pick up again later in their professional careers.

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Sandeep Hiremath is Education Technology Evangelist at MathWorks.