The biological inspired robot project involved designing and building a robot that could autonomously travel 4.9 meters on an inclined track using legs instead of wheels. The robot was inspired by a snail and built from MDF and servo motors. It successfully completed the track but moved unevenly. Alternate designs based on ants were analyzed but proved too complex. Calculations showed the snail design was feasible. Foam was added for traction after initial tests found the drag box hindered movement. With some improvements, the robot could complete the track more smoothly.

1. Biological Inspired Robot Project
Gerard Simon Prosper
Abstract
The third project for the MMAE 232 class is a bi-
ological inspired robot which was able to travel au-
tonomously 4.9 meter on the designated track. Au-
tonomous means the robot cannot be touched while on
the track. Inspiration from nature had to be used as the
basic idea for the robot. The inspiration for this robot
was a snail. The robot was built with Medium Density
Fibreboard ( MDF ) and was propelled by Hitec-425BB
servo motors. The robot successfully moved 4.9 meters
but the movement was not straight and can be improved.
1. Introduction
The idea for the robot has to be inspired and inno-
vated by nature. Biological inspired design was learn-
ing from nature and making a mechanism which is sim-
pler and more effective since nature does not always use
the simplest and most efficient way to the result. The
challenge for this project was letting the robot to move
4.9 meters independently in a straight line on an incline
after being turned on. The track had a slight incline and
decline on it. The change is height was no more than 3.1
mm. A robot with legs were required for this project,
wheels were not allowed to be used as moving mecha-
nism. Materials that were being provided in this project
are screws, 1/4 inch MDF board, 1/8 inch MDF board,
AA sized battery pack, an Arduino board, and Hitec -
425BB servo motors. Other materials were allowed to
be used if needed.
A picture of the Biological Inspired Robot is shown
(see Fig.(1)).
2. Concept Generation and Evaluation
In order to get the best design among the two de-
signs from the group members which are an Ant or a
Snail, a decision matrix (see Table 1) was used. Three
criteria were taken into consideration in this decision
matrix and the three criteria are reliability, ability to
balance, and efforts to program. The first design was
Figure 1. Final Production of Robot
Figure 2. Ant Sketch

2. Table 1. Design Matrix for Two Designs
Design Weighted Ant Snail
Reliability 2 + +
Ability to Balance 3 + +
Efforts to Program 3 - +
Total - 2 3
Total Weighted - 2 8
Figure 3. Analysis for Ant
a hexapod based on ants. Three of the legs moved at
the same time and has a very good ability of balancing
however it is harder to code since it used up 12 servo
motors. The second design is biological inspired by a
snail. The design for the snail only requires one servo.
This will be less time consuming to design in Inventor
and to construct. It also has a good ability in balancing
and is easier to be coded.
3. Analysis
Initially, an ant (see Fig.(2)) was the inspiration for
the first biological inspired design. The ant design re-
quired 12 servos to function well. Based on rough cal-
culation (see Fig.(3)), this design was not acceptable as
the required distance for the servo to move the legs and
what actually the servo can do in reality, the difference
was not acceptable. Even though Gait analysis (see
Fig.(4)) and movement stability analysis (see Fig.(5))
showed good results, the design had to be rejected com-
pletely as it was time consuming and the servo could
not achieve the required torque to produce.
Figure 4. Gait Analysis for Ant
Figure 5. Stability Analysis for Ant
The second design was simpler and the inspiration
was a snail. Only one servo was required to power the
snail robot and based on initial calculations, this design
was acceptable. The gait analysis (see Fig.(6)) showed
positive results. A design was done in Inventor (see
Fig.(7)) to give a better idea on where changes need to
be done so that the robot agrees to the functional re-
quirements and be able to move completely on its own
on the designated track.
In order to ensure that the servo will be able to
move the robot forward, the below calculation was
done:
F = ma (1)
Where F is the force required to move the robot
forward, m is the mass of the robot which is 0.25 kilo-
gram and a is the gravitational force which is 9.81m/s2.

3. Figure 6. Gait Analysis for Snail
Based on the equation, the Force will be 2.45 Newtons.
To find the torque required to move the robot for-
ward, the below equation was used:
τ = r×F (2)
Where τ is the torque required to move the robot
forward, r is the radius which is 0.008 meter and F is
the force required to move the robot forward which is
2.45 Newtons. Based on the equation, the Torque will
be 0.0196 N m.
The torque produced by the servo is 0.320 N m
which is more than 0.0196 N m. Hence, the servo is
able to move the robot forward.
4. Experimental Results
The robot successfully completed the designated
track. It took sometime to finish the track and did not
move as straight as expected but nevertheless, the robot
did what it was required.
5. Discussion
Once we finished designing the robot in Inventor, it
did not take long to construct it as it was a simple de-
sign. On a normal surface, the robot worked perfectly
moving forward. But difficulty was encountered when
it tried to move on the track whereby the robot was not
moving forward. After some evaluation, it was discov-
ered that the Drag Box,(see Fig.(8)) had to be removed
and something else had to be added to provide traction.
Thereafter, foam was used (see Fig.(9)) in replace of the
Drag Box with a holder so that the foam would always
be at a certain angle to allow for grip on the track sur-
Figure 7. Completed Drawing of Snail in Inven-
tor
Figure 8. Snail Drag Box
face. Once the foam was in place, the robot managed to
move over the track. It was not moving smoothly and
steadily but eventually, the robot crossed the finish line
all in one piece. If a bigger piece of foam is used and an
extra servo is added to the design, the robot will be able
to complete the track in a timely manner.
6. Conclusions
It can be concluded that this robot meet the func-
tional requirement and completed the designated track.
With the given time and resources, the robot is as effi-
cient as it could be. Furthermore, the design could work
better if the suggested modifications were made.

4. Figure 9. Foam Addition