Satellite Docking System: An Emerging Technology to Support In-Orbit Satellite Services

The number of satellites orbiting the Earth continues to increase with the growing number of space missions. Owing to the large number of capital investments and manpower required for these missions, it is crucial for the space industry stakeholders to keep satellites in orbit as long as possible and to minimize the rate at which the satellites need to be replaced. 

As a solution, the space agencies are focusing on building the satellite docking system to address various in-orbit satellite servicing and maintenance challenges.

Typically, commercial satellite operators are searching for ways to increase sustainability and security to the space missions that might also reduce the cost of maintaining satellites. This can be accomplished by retaining the current satellites in orbit for an extended period of time. Additionally, commercial operators want to prolong the life of the satellites since this increases the amount of money they can make from the currently available satellites. To achieve this goal, they have chosen to take advantage of in-orbit services such as refueling, repairing, replacement, inspection, manufacturing, and assembly. 

Figure 1 In-orbit satellite service

To perform in-orbit satellite servicing successfully and efficiently, a satellite docking system is required to securely connect with the satellites in order to perform all these services. This aids in extending the lifespan of satellites so they can carry out their tasks.

Thus, the growing demand for sustainable space operations, optimizing satellite operation cost, evolving space infrastructure domain, and evolving space regulations driving the need for in-orbit services are leading to significant growth in the global satellite docking system market. 

According to the BIS Research report, the global satellite docking system market is estimated to reach $1.01 billion by 2032 from $40.3 million in 2021, at a growth rate of 31.3% during the forecast period 2022-2032.

Find more details on this report in this FREE sample.  

In this article, the functioning of the satellite docking mechanism and its importance in in-orbit satellite servicing is discussed further. 

Satellite Docking System for In-Orbit Service Satellites

A service satellite is a satellite or spacecraft that provides in-orbit services to the client satellites to extend their lives and repair them when they encounter problems. The service satellite needs docking mechanisms as well as various additional components and subsystems to safely carry out these activities. The following are subsystems and parts of the service satellites:

1.    Robotic arm in satellite docking system: The robotic arm is the most crucial part of the service satellite since it physically connects with the client satellite first, allowing it to be safely captured and docked with the service satellite to carry out additional assigned operations. The robotic arm is also used to transport space junk, satellites, and abandoned spacecraft between orbits to prevent collisions or to deorbit them to the Earth's surface. These robotic arms grasp the satellite using both electromagnet and mechanical mechanisms. The client satellite is fastened to the service satellites by these robotic arms using unique adhesives. Additionally, in in-orbit servicing, the client satellite is inspected by robotic arms to spot any malfunctioning components and repair or replace them.

2.    Refueling port in satellite docking system: The latest satellite life extension technique is steadily gaining popularity in the space industry. In-orbit refueling is a subset of in-orbit services that involves docking a mission extension vehicle or pod to a client satellite to extend the mission's life span while also transferring fuel from space stations to the client satellite. By evaluating the production and launch costs of the new satellite, it is determined that extending the mission's lifespan while using the current satellite is the most cost-effective strategy.

3.    On-board computers in satellite docking system: To analyze intricate algorithms and the data gathered by many sensors during docking, the service satellite's on-board computer is crucial. Both volatile and non-volatile memory is abundant in these computers, which also have a fast processing speed. In order to safely dock the client satellite with the service satellite, the on-board computer of the service satellite processes information from the client satellite, such as alignment, altitude, and rotation and movement speeds. This information is used to position the robotic arm or docking system in accordance with the client satellite's alignment.

Due to its complexity and potential for a collision, if something goes wrong, this process calls for high-performance computers. It also needs inspection software to check the client satellite and find the broken components.

4.    Electromagnet attachment in satellite docking mechanism: A remote manipulator system uses the electromagnet attachment mechanism as its end effector. It consists of two electromagnets, one installed on the docking plate's surface and the other suspended from it by a suspension system made of springs on a base plate housing with end pole pieces. Each electromagnet has a pull-in coil, a U-shaped magnetic core, and two holding coils. The docking plate or grapple fixture facilitates attachment to a target satellite or object when the electromagnets' attractive force is applied.

A power supply and a separate control circuit are given for each electromagnet's pull, and one holding coil is used to regulate the procedure and deliver energy to the electromagnet. This aids in stabilizing and safely holding the target satellites or space debris until the in-orbit service is carried out. This suggests that for the service satellites to hold the target items, the electromagnet attachment mechanism is crucial.

5.    Rotational alignment guides in satellite docking system: A tool deployed on the service satellite called a rotational alignment guide allows it to keep track of the client satellite's rotation and securely capture it. It also directs the robotic arm to spin the customer satellite so that it is pointed at the in-orbit refueling station's refueling port or value. Additionally, it facilitates the safe repair and replacement of the malfunctioning item by rotating the client satellite and docking it with the in-orbit service satellite. The on-board computer and robotic arm are both connected to the rotational alignment guide, which processes the information regarding the rotational angle and corrects any errors automatically.

6.    Sensor unit in satellite docking system: For the service satellite to estimate and determine the operating status of the client spacecraft, the sensors are a crucial piece of equipment. Electro-optical, infrared, pressure, temperature, motion control, light detection and ranging (LiDAR), laser rangefinders, radars, and sounders are some of the main sensors used in service satellites. They assist in estimating the client satellite's distance, altitude, speed, and alignment and transmit information to the on-board computer to position the robotic arm safely during satellite capture. As part of in-orbit inspections, the client's satellite's problematic components and gadgets are also identified using LiDAR sensors and electro-optical sensors. 

These sensors are installed all around the subsystems and parts in order to monitor their operational status continually and identify any deviations from the expected range of operation. 


Space industry innovators are constantly attempting to create a compact, lightweight, and reliable satellite docking system that may be utilized to dock satellites to a host spacecraft for maintenance and service transfers. Small satellites can be docked using an innovative satellite docking mechanism, which decreases the risk of collision damage while allowing power, data, and fluid to be transferred between the vehicles.

Interested to know more about the growing technologies in your industry vertical? Get the latest market studies and insights from BIS Research. Connect with us at  hello@bisresearch.com to learn and understand more. 

Webinar - LoRaWAN : A New Age of Agricultural IoT

Get DeepTech Insights in your Mailbox!

Posts by Topic

see all