Design and Simulation of an Electric Powertrain for Aircraft Towing application

`Mototok Twin 7500NG - Aircraft Towing System`

All the concerns with traditional aircraft towing for years — whether that’s operator training, collisions due to miscommunication, or defective equipment due to insufficient maintenance has sparked the realization that there needs to be a better way.

Mototok, a company founded in 2003, came up with a revolutionary technology. They designed an aircraft towing system, an unmanned automated guided vehicle, that weighs 2,100kg and can tow a Boeing 737 weighing up to 75,000kg! I found this to be insanely cool, and so I decided to model and simulate its electric powertrain using MATLAB/SIMULINK.

Below are two figures that represent the towing done to move the aircraft:

This represents the traditional towing method via a tow truck/tractor.

How towing is done using the ATS created by Mototok.

Both powertrains can tow a Boeing 737, but Mototok’s ATS does it with:

Fewer emissions due to its electric drive.
Extremely powerful electric motors – driven by high performance, maintenance-free batteries with high recycling capability.
Being radio remotely controlled — only 1 person required for operation (as opposed to at least 4 that are required for towing with a truck/tractor). The operator is able to move around to see every vantage point, ensuring high safety and reliability.
Extreme compactness.
Little to no maintenance costs.

Overview of the entire model:

Subsystems:

Electric powertrain
Vehicle body

Results of the simulation: 20 second tow test

Since all the calculations have been done with a tow time of 20 seconds at max speed, the final 20 seconds of the results are used The ATS is able to move the aircraft by 16.26m, giving a speed of about 0.81m/s. According to ATS data, it can travel at a top speed of 1.05m/s, which is not too far from our results here and is fairly accurate.

Capacity: state of charge and distance

The current powertrain is capable of towing the aircraft for about 1190 seconds, which is about 20 minutes. Beyond that the battery would be depleted to 0% and would need to be recharged.
The total distance that this powertrain can tow the aircraft for in those 20 minutes is about 950m.

Velocity:

The ATS reaches its top speed of 0.81m/s at around 100 seconds, and moves constantly at that speed until battery runs out.