## 3 Use-Case-Based Categorisation of Technologies
### Use Case Examples and Derived Requirements  
#### 3.2.1 Automation and Teleoperation  
A network for automation and teleoperation covers all use cases around (mobile) machines, their automation, online supervision and teleoperation as control and support by human operators. The automation of a machine is defined as a (partial) takeover of tasks by a machine or automated system given an assigned task from outside and without further or with minimal input from a human. Teleoperation is when the actual command input for the operation performed by a (mobile) machine or system is done at a distance. This approach has the direct consequence of removing on-site operators and maximising safety involved in active operations [1]. Examples of use cases for this category include:  
* Supervision of automated loaders or trucks transporting material
* Tele-remote support of loader picking up material
* Supervision and tele-remote combination while drilling
* Robotized ground- or air-based remote inspection of critical areas In conjunction with these usages, the following data must be transmitted:
* Machine mission, route, action list (down)
* Health state and safety status (up/down)
* Live video and/or point cloud feed (down)
* Control and telemetry commands (down)  
A wireless technology must fulfil the following requirements to be appropriate and function effectively for the use cases mentioned above:  
* Constant coverage and seamless roaming in working/tele-remote areas
* High-speed connection (~10 Mbit/s) for each machine (possibly higher for VR applications)
* Softly bounding time delays for single way (<1000 ms) for supervision
* Softly bounding time delays round trip (<40 ms) for control (not safety-relevant)  
The level of automation and level of human interaction with the machine results in different requirements towards the communication system. Each level of automation can have different requirements [31]. In Ref. [3], the authors consider different levels of automation established for public roads. In Ref. [32], the design of Levels of Mine Navigation Automation (LoMNA) for underground navigation can be found, which also extends the requirements towards communication.  
No automation or driver-assisting automation levels resulting in needs for teleoperation set the highest requirements for an installed network, requiring a high data rate coupled with low latency, as the operator becomes part of the control loop. In order for this communication to be seamless and control the machine efficiently, high throughput (e.g., for high-resolution video streams) and low latency in the wireless technology used is required [32; 33].  
When the level and robustness of automation rises past a certain level, network requirements can be limited by far, even towards a point where there is only a minimal and/or a decentralised network required for the operation of equipment supporting an inter-machine communication and a basic minimum accessibility for higher-level commands (including an emergency stop) [3; 31].  
Considering the requirements for low latency and high data rates in automation and teleoperation, as well as the clusters shown in Figure 4, the possible network technologies are limited to those in the GHz spectrum, such as 5G or Wi-Fi. These technologies operate in a frequency spectrum that supports high data rates and low latency, but also require wireless installations to have near or direct line-of-sight (LOS) connections between the sender and receiver [34]. Given the constraints of the underground environment, a dense network installation is necessary in order to provide adequate coverage for teleoperation. The network must provide coverage near the mobile machines, as the rock mass limits the range of the network. As the automation and teleoperation areas move or change, it becomes more challenging to maintain the network, as the coverage is very limited in these areas [35].