Robot Setup

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Setup for motion capture

During task benchmarks, the pose of the robot will be captured by a motion capture system. For this, a "Marker Set" (provided by RoCKIn) will be fitted to the robot.

top view of the Marker Set

The base of the robot must be provided with a vertical-axis M4 nut (or threaded hole) so that the Marker Set can be screwed onto it from above. For this, on the bottom of the Marker Set (the side facing the floor) there is a protruding M4 screw (visible in the first picture). The team can freely choose the location of the M4 nut (or threaded hole). High places and/or places without nearby objects that can hide the markers are preferred. M4 is a standard ISO metric thread with an outer diameter of 4 mm.

Teams must provide the translation between the origin of the reference frame of the base of the robot and the center of the M4 nut. This translation is composed of the displacements along the X, Y and Z axes of such reference frame. Precisely, each team is required to provide a text file called displacement.txt containing four lines of text having the form

X = dx
Y = dy
Z = dz

where dx, dy and dz must be substituted with the numerical values of the displacements described above, expressed in meters. With this file, the team specifies that the center of the M4 nut is at coordinates (dx, dy, dz) according to the reference system of the base of the robot. Important! Teams who do not comply with the axis convention used by ROS [1] for axes (i.e. X pointing forward, Y pointing left, Z pointing up) must add a second text file, called axes_orientation.txt where they describe clearly, in free text, how their axes are oriented.

Files displacement.txt and (if required) axes_orientation.txt must be written on the USB key provided by RoCKIn, in the same directory where the robot writes the data required by the benchmark: see "this document":http://rm.isr.ist.utl.pt/attachments/622/robot_data.txt for details. Please note that the files must be saved on the USB key each time the robot executes a benchmark, even if they are unchanged wrt preceding benchmarks.

Mounting the Marker Set on the robot requires that there is a free volume of space (cylinder, diameter 180 mm) above the M4 nut. The Marker Set weighs 300g approximately. The protruding screw on the bottom of the Marker Set is 25mm long. The robot must avoid collisions between the Marker Set and other objects (when assessing collisions for scoring, the Marker Set is considered as a part of the robot).

A CAD model of the Marker Set is available in the "Files" section.

Setup for pose logging

During task benchmarks, robots are required to log pose data (see "List of variables to be logged" for each benchmark). These data must be expressed in the reference frame of the testbed.

The reference frame will be clearly marked on the testbed. It will be possible for teams to define such frame in their robot before the start of the competition. The following picture shows a possible testbed reference frame.

!example_frame_atHome.png! Example of testbed reference frame for RoCKIn@Home. Z axis points towards the reader.

Saving robot data

RoCKIn requires that robots save some data when executing the benchmarks. The modalities for this are explained by "this document":http://rm.isr.ist.utl.pt/attachments/622/robot_data.txt.

Important! While the content of the data files saved by the robot is not used for scoring, the existence of such files and their compliance to the specifications does influence the score of the robot. Teams have the responsibility of ensuring that the required data files are saved, and of delivering them to the referee at the end of the benchmark. These aspects will be noted on the score sheet and considered for team ranking.