Nanogram Robotic Soccer

Since its inception in 1997, the RoboCup soccer competitions have become a premiere vehicle for driving and showcasing advances in mobile robotics research and agent co-operation. The tournament provides an international venue for students and academics to focus research efforts. By choosing a popular topic such as soccer in a competition format, RoboCup helps motivate students and the public alike.

The competition creates a constrained task environment to develop and test complete robots covering a full range of challenges in the field of robotics and artificial intelligence. Soccer was chosen as a suitable competition activity because it includes all of the key aspects of robotics and artificial intelligence and has social appeal around the globe. The competition was extended to include a league of micron-sized robots which has been dubbed the Nanogram league. The international RoboCup championships took place in Atlanta, USA, July 2007 with the league's premier. The goal of this league is to use autonomous microrobots smaller than 300μm to perform a series of soccer related tasks.

The goal is for the robots to be entirely driven by computers using visual servoing and other control strategies. The robot is considered an autonomous agent and is not be connected by wires or tethers to the outside world, which means that power for motion must be harvested from the environment. To win the competition, a robot must be fast, agile, and capable of manipulating objects in the micro-world.

There are 3 compulsory exercises:

Two Millimeter Dash: The robots must travel as fast as possible from one goal to the other.
Slalom Drill: The path between goals is blocked by stationary "defenders" that the micro-robot must avoid as it races between the goals.
Ball-handling Drill: The robots must push as many balls as possible into the goal within a 3-minute time period.

The Advanced Robotics and Mechatronics lecture exposes students to the multidisciplinary challenges of robotics by presenting them with a large mechatronic problem to be solved in a semester time frame. At the beginning of the semester, students form teams and are given a robotic task. These tasks are open-ended and require skills of creativity, teamwork, organization and firm theoretical and practical backgrounds for the students to succeed. The lecture culminates in a tournament between teams.

Previously, this course has centered around the use of mobile robotic systems for performing the tasks. With the advent of the Nanogram league, IRIS has transitioned the course to the micro scale. The shift to microrobotics allows IRIS to expose students to current methods and results in the fields of micro- and nanotechnology. This provides the students with an opportunity to work closely with cutting-edge research in an approachable format. The teamwork aspect of the competition helps students with their organization and project management skills, while the international nature of the competition provides a motivation level that cannot be approached by traditional lecture methods. Over the course of the project, students gain experience in a variety of topics such as artificial intelligence, integration of visual tracking, micro-fabrication, and wireless actuation methods.

Although the competition has been developed with "suggested" propulsion methods, contestants are free to design their own actuation strategies. Researchers at IRIS have developed our own microrobot technology using a unique propulsion method which is capable of performing in the Nanogram domain. This robot consists of two small pieces of soft magnetic material with overall proportions such that the robot can be rotated in place by external magnetic fields. The two magnetic bodies are separated by a gold spring and base frame. When subjected to an external magnetic field, the two pieces magnetize and create an attractive force between them. By oscillating the external field the body and spring system are driven to resonance. Combining this with phase-locked electrostatic clamping from electrodes built into the field, enables momentum transference from the impact between the bodies. This allows the robot to be driven around the specialized substrate with both velocity and orientation control. By relying on unique resonant frequencies of different devices, multiple devices can potentially be simultaneously operated on the same field.

Students are provided with a working prototype at the beginning of the course. The students' participation in the lecture then takes various forms depending on the individual team proficiencies. Tasks such as modeling and device design can be handled by students interested in microrobot and MEMS, while topics such as tracking, control and artificial intelligence can be handled by students more interested in these aspects. Although students are able to model and design their own microrobots, IRIS staff are utilized to expedite the manufacturing process. One challenging part of the students' task for the semester is managing human and technical resources during a fast paced course which culminates in a local Nanogram competition.

2009 Competition

Two teams of six students participated in the local ETH tournament, and were able to successfully complete all three tasks at the Institute. The winning team then participated in the international competition in Graz. Four other participants registered for the competition including Johns Hopkins University, The University of Waterloo, Universite de Sherbrooke, and the U.S. Naval Academy, but only the USNA was able to field a moving competitor. The ETH team successfully completed tasks one and two, but was unable to complete the ball handling drills at the international competition. Even so, the ETH team was able to win the competition and retain their international champion status.

2007 Competition

Three teams of six students competed in the local ETH tournament. All three teams completed both the dash and the slalom drills. Although two teams demonstrated automated ball handling prior to the local competition, only one team successfully completed the task during the actual competition. Upon completion of the local event, the winning team was allotted two weeks to polish their system and prepare for the final competition in Atlanta.

A total of five teams from Carnegie Mellon University (two teams), Simon Fraser University, U.S. Naval Academy, and ETH competed in the Atlanta RoboCup Nanogram tournament. Of these teams, three implemented variations of the electrostatic scratch drive and two teams proposed systems using magnetics. The two teams that employed magnetics were the only teams to successfully complete the dash and slalom drills and the IRIS team was the only one to successfully complete the ball handling drill. The IRIS team won all three categories of the competition.