The first problems addressed when the design started were the vibrations, angular velocity and thrust reversing during main docking procedures, but also to delete the human factor during this procedure as well as time elapsed during the maneuvers and maintenance practices for the complex systems. In the other hand we wanted by development, to standardize orbital capsule and module constructions by implementing our modular docking systems and develop an autonomous construction system in order to build safer, cheaper, faster , but also modular such as lego bricks 

The first design proposed, was a petals based docking system in which the male module will fit on a 1.5 meter female receiver an then engaged with a radial petals-like couplers

The flaws with these mechanism was the vibrations transference and also the lack of redundancy when the module is fitted and engaged.

The definitive docking system called QUICK RELEASE DOSCKING SYSTEM (QRDS) is based on an assembly mechanic called quick release. When the module is docked from the ground, it will come with a half-thread docker that will previously be docked to the male terminal and when they do the initial Docking, the capsule will be flush with the female receiver terminal, generating a thread through which it will pass the docker.

The docker is one meter long and the thread pitch is 50cm per revolution. It is 2.5 revolutions and once it reaches its top, the top will have hooks that will engage as a quick release system, typical of car steering wheels.

Once the mechanism was devised, a problem arose, which was how to turn this docking nut in weightless conditions, and where a large amount of energy is needed to apply force. We all take into account that we have these thrusters that control the attitude system of any mechanical body of any spacecraft and are used to move and navigate. It was initially decided to place these thrusters in each of these polygons so that by means of an algorithm when activated, all the thrusters will pull from one side, they will squirt from one side and push clockwise or counter-clockwise to thus being able to tighten or loosen, dock or undock.

Since what the modules are going to assemble are the thrusters, a robotic arm will also be exposed instead of an actuator. It is no less expendable since in case of failure there must be an alternate way that supports the assembly of the modules.

Methodology:

The assembly design that was generated was the following:

We considered the variability of the assembly, with the fact that an electromagnetic field may be applicable to support the assembly and to activate safety sensors and, at the same time, its fastening systems.

The luminosity of our Sun varies by just 0.1% throughout its 11-year solar cycle, the "Effects of Solar Variability on Earth's Climate" exposes some of the surprisingly complex mechanisms by which solar activity can make themselves felt on our planet [4]. Observations show that the velocity of a coronal mass ejection (CME) through the space gulf can be as high as 2500km / s [5].

Some cosmic rays are compared with forces like hurricanes on earth, so that amount of force will be used in the simulation, being analyzed with a medium category of force for the piece [6].

A force scaled to the geometry of the part was selected, taking into account the mass of the Module to be assembled as loads and taking a diameter of 3m for the docking system, a material of Cast Steel ASTM A48 Grade 40 was also used for the simulation .

For the analysis a force will be taken into account Taking data from the modules the analysis remains:

For NASA / Boeing

Node 1. Unity.

Figure 2. Technical data of the Node 1. Unity [2].       Figure 3. Node 1. Unity [2].

Figure 1. Image of the designed docking.

The assembly system will be tested for mechanical stresses typical of an assembly mechanism:

Of the (types of mechanical forces in an assembly)

Traction, compression, torsion, flexion, etc.

In this case, the mechanism's traction and torsion analysis was performed, using data from an assembly module, taking into account mechanical stresses that the system has to withstand, such as module mass or solar storms.

Results of mechanical simulations:

-Simulation of the assembly part subjected to Traction.

-Simulation of assembly parts subjected to traction.

-Simulation of the assembly part subjected to Torsion.

-Simulation of assembly parts subjected to torsion.

It is thought that the actuator of the assembly is magnetic in order to be able to control the speed at which the other module arrives, and in turn, in the assembly process, act as a shock absorber, minimizing risks.

The system to generate an electromagnetic field will function as an actuator for the module's control systems, thus creating an alignment in the gyroscopic system of the assembly disk in the ship and which in turn helps to accommodate the assembly system by counteracting part of the vibrations that may be submitted [7].

Figure 5. Exemplification of the operation of a torus to generate magnetic fields.

Figure 6. Location of magnetic field in assembly part.

Figure Idea of where the magnet would be placed in the assembly part.

Which will help in the same way, that an approach sensor is activated and can regulate the magnetic field and thus accommodate and activate the assembly system by activating the fasteners of the system.

Another idea of the field generated in the mechanism is that it can be adjustable, to coming solar storms [8], providing greater protection of the module in space.

Figure 7. Location of the toroid for generating the regulatory magnetic field in the assembly.

For the chosen materials:

The chosen materials are suitable for space environment applications due to its high performance properties and feasibility to manufacture in space building facilities In order to assure the quality of the product we implemented additive manufacturing and rapid-prototyping techniques for validation and verification process of design and manufacturing requirements and specifications.

For the Robotic arm

With the implementation of the autonomous robotic arm in charge of assisting the docking and assembly of modules, ships, nodes and / or parts in the ISS, in addition to fulfilling other tasks such as: Inspection, maintenance, drilling, screwing, etc. The design and calculation of this is carried out using the "Solidworks" design software, programming through FANUC as well as the application of IoT.

User Software Interface 

For the Interface, we made a deep research on how it would be the best way to place the functions on a screen for the user's comfort. We landed on a user-friendly experience with an intuitive flow.

• POT. (2015) Reference Guide to the International Space Station. National Aeronautics and Space Administration.
• POT. (2017) International Space Station Facilities, Research in Space, 2017 and Beyond. National Aeronautics and Space Administration.
• Robert Dempsey, Dina E. Contella, David H. Korth & Michael L. Lammers. (2018) The International Space Station: Operating an Outpost in the New Frontier.
• NASA, CSA, ESA, JAXA, ROSCOSMOS & ISA. (2019) International Space Station Benefits for Humanity, 3rd edition.
• Steven, M., Cebon, D., & Ashby, M. (2012) Materials Selection for Aerospace. National Aeronautics and Space Administration
• NASA Marshall Space Flight Center (2006). Fracture control requirements for composite and bonded vehicle and payload structures, MSFC-RQMT-3479, Marshall Space Flight Center (MSFC), AL, USA.

[1] Discovery Shuttle Mission Report: STS-124-29 https://www.nasa.gov/centers/ames/spanish/news/releases/STS-124_mission_update.html

[2] Reference Guide to International Space Station.

      National Aeronautics and Space Administration.

      Utilization Edition September 2015.     

[3] NTRS - NASA Technical Reports Server.

      The ISS 2B Photovoltaic Thermal Control System (PVTCS) Leak: An Operational History.

      https://ntrs.nasa.gov/citations/20140012987

[4] Solar variability and terrestrial climate.

      https://ciencia.nasa.gov/ciencias-especiales/08jan_sunclimate

[5] Weather conditions in space.

      NASA - Living in the sun's atmosphere.

      https://stereo.gsfc.nasa.gov/spaceweather/SWpost_SP.pdf

[6] Hurricane force categories.

      https://huracanes.fiu.edu/aprende-sobre-huracanes/vientos-fuertes/categorias/index.html#Categoria%203

[7] Cupich, M. and Elizondo F.

      Magneteorological dampers.

      https://core.ac.uk/download/pdf/76600297.pdf

[8] A force field for astronauts.

  https://ciencia.nasa.gov/science-at-nasa/2005/24jun_electrostatics

Alloys we used

AerMet 100

Ti-6Al-4V

Ti-4,5AL-3V-2Fe-2Mo

Ti-6Al-25n-25n-2Zr-2Mo

https://s3.amazonaws.com/astreo.spaceapps/home.html

Creation of the attachment within the modular capsule;

Designing an easy docking assembly system

Female docking.

These would be together with their design thought for modular use, so their geometry will not affect different types of joints. As easy and universal use, these were main ideas to work together in links either in satellites or for the design of the structure.

Creation of the modular capsule

The prototype was manufactured and the materials were evaluated in order to conclude which is the best material to develop the robotic arm.

Robotic arm

Design-user interface to manipulate the robotic arm.

Wireframes provided;

The robotic arm design is not only for docking or assembly, it could even do more tasks at the ISS, such as repairs, maintenance, assistance, etc… This could be realized by an autonomous system or manual, being more efficient and safe for the ISS and the astronauts, with the difference that the arm could move in all the ISS by itself.

App-Tablet size

https://s3.amazonaws.com/astreo.spaceapps/home.html

References: List the data and resources used in your project*

Draw io , UML , Math lab

Solidworks 2020, Cura: Ultimaker.

FANUC, Arduino, Proteus.

Autodesk Inventor Professional 2018

Figma, Photoshop and Premier Pro.