Environmental Engineering Reference
In-Depth Information
Fig. 9. Direct aids provided by the platform. On the top: aids to select the correct brick. On
the bottom: aids to place the brick in its correct position.
session, the aids were displayed only when the trainees request them by pressing the help key.
Finally, during the third and fourth sessions, the aids were displayed only when the trainee
requested them as in the second one, but they had also made at least one attempt of selecting
the correct brick, i.e. the trainees had to try selecting the correct brick by themselves before
being able to receive the aid. Each requested help was automatically logged as one aid.
In both groups, when trainees selected an incorrect piece, the platform played a “beep” sound
and displayed a message to indicate the mistake. To evaluate the performance of the trainee
the system also logged the number of incorrect pieces selected. Additionally, the order of
the steps was fixed and numbered from 1 to 75, therefore both strategies followed the same
building order.
4.3 Participants
The experiment was undertaken with 40 undergraduate students and staff from CEIT,
the University of Navarra and TECNALIA. Following a between-participants design, each
participant was assigned to one of the two experimental groups (20 participants in each
one). For the assignment of the participants to the groups, first they filled in a demographic
questionnaire whose answers were used to distribute them along the two groups in an
homogeneous way. In the direct aids group, 48% of participants were female, the average age
was 33 with a range from 24 to 50, and only 32% of participants did not have any experience
with LEGO™models. Meanwhile, in the indirect aids group, 53% of participants were female,
the average age was 36 with a range from 26 to 48 and only the 37% of participants did not
have any experience with LEGO™ models. All participants reported normal sense of touch
and vision and did not have experience in using haptic technologies.
Before starting the experiment, participants signed an informed consent agreement and they
were informed that if they achieved the best performance of their group, they would receive
areward.