The document describes a student robotics project to design and test a remote-controlled robot capable of performing tasks required to build a colony on Mars, such as navigating obstacles and picking up building materials. The robot was tested in a mock Martian terrain containing obstacles and items to pick up. While the robot could navigate the terrain and pick up an item, it struggled to accurately drop off the item at the destination. The document discusses improvements that could enhance the robot's ability to complete the required tasks.

1. Robotics ENGG30151
Nottingham Trent University
School of Science and Technology
Tristan Procida N0972073
Rohan Patel N0914092
Michael Baker N0918953
Jake Thompson N0869436

2. How to build a
colony on Mars
• Humans are currently
orbiting the planet in a
space station
• Robots need to be utilized
to construct the colony
remotely
• The robots require a
suitable end-effector to
pick up and drop building
materials
• The robots also need to be
easily maneuverable to avoid
Martian obstacles

3. Background
• Our project involved constructing a remote-controlled robot capable of imitating the
actions of robots sent to Mars to build a colony in 2035. The robot was designed to
navigate obstacles and pick up items, critical requirements for building a colony on Mars.
This project is significant in contributing to the development of technologies that can
help establish a sustainable living environment on Mars and reduce the risks and costs
associated with sending humans to Mars.
• In-order to determine the potential success of our project, we will be conducting a
feasibility assessment that will include a mock terrain with obstacles to navigate and
items to pick up. This assessment will provide valuable insights into the capabilities of
our robot and its ability to perform the tasks required to build a colony on Mars.

4. Why colonize Mars?
• Establishing a permanent human settlement on Mars would provide a safety net
in the case of a catastrophic event on Earth such as nuclear war or natural
disasters. The Mars colony would serve as a backup plan to ensure the survival of
the human species (G. Madhavan Nair., K.R. Sridhara Murthi., M.Y.S. Prasad.,
2008).
• Mars colony would provide new opportunities for scientific exploration and
research (G. Madhavan Nair., K.R. Sridhara Murthi., M.Y.S. Prasad., 2008).
• Economic opportunities arise providing the creation of new industries with
opportunities for resource extraction, construction and tourism (Goldman Sach,
2017).

5. Initial Ideas
When designing a robot destined for mars the outcome for the mission needs to be considered throughout
the design process. This robot needs to be capable of moving material around and maneuvering the Martian
terrain.
There are 4 main wheels to consider when creating a robot: Standard wheels, Spherical wheels,
Castor and Omnidirectional. Each option has its own benefits and ideal situations.
• Spherical wheels are typically small and allow for multidirectional movement, however, are difficult to
connect a motor drive.
• Standard wheels are cheap and easily maintained however require a steering axle to turn which creates
a large turning circle.
• Castor wheels consist of a simple wheel attached to a pivot and then offset from said pivot allowing the
wheel to be orientated towards the direction of travel. This design makes it extremely difficult to power and
steer the wheels.
• Standard Omni Wheels are like Meccanum wheels, but with a simpler design. They have a series of smaller
wheels mounted around the circumference of the main wheel, allowing for omnidirectional movement.
However, unlike Meccanum wheels, all of the smaller wheels on an Omni wheel are oriented in the same
direction, meaning that they can only move in one plane. These wheels are commonly used in mobile
robotics, particularly for small, agile robots that need to move quickly and easily in any direction. When
placed at 45-degree angles on the robot body these wheels can allow the robot to move holonomic.

6. Rationale
• Omnidirectional wheels
• Manoeuvrability and adaptability: Omnidirectional wheels are versatile and adaptable to different
environments and terrain types, making them ideal for use on an unpredictable surface like Mars. The
omnidirectional wheels allow the robot to utilise holonomic movement, without the need to change its
orientation, making it easier for the robot to navigate around obstacles which would be present on the
surface of Mars.
• Efficiency: Omnidirectional wheels allow a robot to move efficiently, as they can move in any direct ion
without having to turn or reposition themselves. This means the robot can complete tasks more quickly and
with less energy consumption which is important for a vehicle which may have a finite supply of energy or
difficulty create repairs due to its remote working environment.
• Stability: Omnidirectional wheels provide greater stability and balance to the robot, as they distribute the
weight evenly across the wheels. This makes the robot less likely to tip over or become stuck in uneven terrain
which is essential due to the remote working environment of the robot.
Overall, the use of omnidirectional wheels allows an autonomous robot to move more efficiently and effectively on
Mars, while also reducing the risk of damage to the robot and increasing its ability to complete tasks successfully
which is why they have been implemented on our robot.

7. End effector design
There are various types of end effectors that could be used in a robotic mission to Mars, each with their own specific
operations:
• Gripper: A gripper is a common type of end effector that can grasp and hold objects securely, useful for collecting
and delivering objects such as construction materials for the colony.
• Scoop: A scoop end effector can be used to scoop up loose materials, such as dirt or sand. It could be useful for
moving granular materials around on the surface of Mars.
• Magnet: A magnet end effector can be used to pick up metallic objects, such as screws or bolts. It could be useful
for constructing/deconstructing structures or repairing equipment.
• Drill: A drill end effector can be used to bore holes in rock or soil. It could be useful for collecting samples or
installing equipment.
• Cutter: A cutter end effector can be used to cut or slice materials, such as tubing or cables. It could be useful for
performing maintenance tasks or modifying equipment.
The choice of end effector would depend on the specific tasks required in the mission and the characteristics of the
objects to be moved.

8. End effector design
To fit the brief of re-locating a 10-gram building block from a
source destination to a final resting destination, a gripper would
be the ideal choice. This is due to the ability to add additional
degrees of freedom in the Yaw rotation around the y-axis.
Allowing for finer movements and creating a greater ability to deal
with complications whilst completing the Mars mission.
Materials:
- 5mm Clear acrylic
- Small fixings
Manufacturing methods:
- Laser cut
- Manual assembly

9. End effector design

10. Robot design
Main components:
- Omnidirectional wheels controlling the movement of the vehicle.
- Extruded aluminium creating the support for the base and pivot
arms of the vehicle.
- Micro-servos - for the operation of the gripper.
- Servos - for the movement of the pivot arms.
- Raspberry-Pi controller - complete control of the physical
components.
- Acrylic base plate.
- Intergrated Wi-Fi shield in the raspberry pi.
Assembly method:
- Basic part assembly method.
- Small fixings used.

11. Test environment
+ Simulation
• This image shows the test environment used to simulate
the mars mission. It features several obstacles that need
to be navigated around with a designated dock for the
robot and dropping area for the brick.
• One limitation this set up has compared to actual
situations that would be faced on mars is that
this simulation is within a completely 2D protected
environment.
• The real situation would involve rocks, bumps and the
possibility of dust or windstorms. This could affect the
performance of the components or knock the brick free.
"The winds in the strongest Martian storms top out at
about 60 miles per hour"(NASA, 2023).

12. Manual
maneuver
• Our robot is a remote-controlled robot that can be connected
through a hotspot. This allows the operator to be always in
control of the robot and direct where it travels. The robot has
various functions; because to its omnidirectional wheels, it can
move in any direction, including forwards, backwards, left, and
right. Also, it includes a variety of sliders for the operator to use
to effectively manage the robot, the operator will be required to
use the various controls to make use of a particular component
of the robot. In addition to this, the robot is equipped with a
variety of joints, and the operator can utilise the appropriate
slider to enable the robot to move in any of its available joint
configurations. The robot also has the capability of controlling
the end effector, which enables it to pick up the brick in the
appropriate manner.
• When we were carrying out our mission, we took several
steps to ensure our safety, and one of those safeguards was to
maintain a safe distance away from the robot whenever it was in
operation.

13. Manual maneuver

14. Code
# Initialisation
import merlin_hw
import time
from importlib import reload
reload(merlin_hw)
time.sleep(1)
merlin_bot=merlin_hw.robot()
control_merlin=merlin_bot.get_robot_control_layout()
merlin_bot.start()
display(control_merlin)
The above code was utilized to operate the robot by presenting sliders on the device connected wirelessly. The
values of the sliders corresponded to the movement of the wheels, including rotation, forward and backward,
left and right movements, and the three motors attached to the arms and the end effector.

15. Autonomous maneuver
Key locations
• 𝑀𝑇𝑃(𝑆𝑡𝑎𝑟𝑡)
1.005
0.2
0
• 𝑀𝑇𝑃(𝐵𝑟𝑖𝑐𝑘)
2
0
0
.905
• 𝑀𝑇𝑃(𝐷𝑜𝑐𝑘)
1.005
1.55
0
Another way to traverse the environment was by using autonomous movement. This can be achieved by coding in a set route
using the supplied locations of key locations and obstacles to create a route. Another way of achieving autonomous
movement is by implementing an LIDAR or similar device to detect and measure distance to obstacles to aid in routing
around obstacles. This option was not considered for our test due to the environment being 2D and therefore unable to be
detected using LIDAR.

16. Results
During the demonstration phase of the project, we successfully navigated the mock terrain,
avoiding all obstacles using the sliders on VSCode to remotely control the robot through a
WiFi hotspot.
While the robot was able to pick up the designated block during the trial, we encountered
issues when attempting to deposit and drop it off at the end of the trial.
Despite this setback, the robot was able to physically reach the end goal of the trial,
demonstrating its capability to navigate the terrain and perform the necessary actions
required for building a colony on Mars.

17. Discussion
• Our project encountered limitations and challenges during the demonstration but provided valuable insights for future improvements.
• The robot's end effector extended too far from the main body while dropping a block in the goal zone, causing the reach to overshoot the
desired location.
• Repositioning the entire robot was necessary, which did not fulfil the project's requirements.
• A prismatic joint can be incorporated along the arm of the robot to adjust the distance between the end effector and the main body,
improving flexibility and control over the robot's movements.
• With this joint, the robot can accurately and efficiently drop off items in specific locations without complete repositioning.
• Another point of difficulty with our demonstration was the actual interaction and control of the Robot. When operating the robot arm for
example, sliders were used which lacked accuracy and was difficult to determine where the end effector would end up.
• A solution to this could be to map the control of left and right motion for example to two adjacent keys. This would be easier to control the
robot arm even with the delay and incremental adjustments would be easier.
• End effector was a gripper which had difficulties in opening and closing. This was mainly due to material choice and the spur thickness. This
meant one of the gear's spurs broke off.
• A solution to this would be a smaller gear ratio with less spurs so that the spurs individually would be larger, withstanding more stress. This
would also allow the material to remain as acrylic which benefits the project as it is relatively cheap to alternatives.

18. Future improvements
• Reduce the size of the robot's effector arm. This will prevent the overshoot of the docking zone
and drop off position.
• Add a prismatic joint to create an additional degree of freedom, improving flexibility and control
over the robot's movements.
• Change the control method of the robot. The sliders used to control the movement had dead
spots meaning the robot could easily overshoot positioning or encounter obstacles. A WASD
control could be incorporated with addition key bindings to control the arms and effectors, these
could be programmed with higher resolution of control.
• Altering the material of the end effector to prevent breaks in the spurs and allowing greater
angular torque to create a greater grip strength.
• Incorporating gear ratios to allow for a greater grip strength.
• Increase the surface area of the gripper surface.

19. Referencing:
• Goldman Sachs, 2017. Space Exploration: The Next Investment Frontier. Retrieved from
https://www.goldmansachs.com/insights/podcasts/episodes/05-22-2017-noah-
poponak.html
• G. Madhavan Nair., K.R. Sridhara Murthi., M.Y.S. Prasad., 2008. Strategic, technological
and ethical aspects of establishing colonies on Moon and Mars, Acta Astronautica.
Volume 63, Issues 11 – 12, Pages 1337 – 1342.
• NASA. (2023). The Fact and Fiction of Martian Dust Storms. [online] Available at:
https://www.nasa.gov/feature/goddard/the-fact-and-fiction-of-martian-dust-storms.