Mortis

==Design==
[[File:Mortis series 1 official image.JPG|thumb|left|Series 1 appearance]]
Mortis's design evolved throughout its appearances, being a tracked robot with a tank-like appearance, a top speed of 9mph (later 12mph) and an electrically-driven axe capable of firing quickly and causing tremendous damage to other opponents' armour. This axe featured a custom head modelled after Japanese [http://en.wikipedia.org/wiki/Tant%C5%8D tantō] knives for optimal armour-piercing capabilities, and could strike up to three times a second with the equivalent force of a .38 Magnum rifle fired at point-blank range. Being one of the most technologically-advanced competitors on the show, Mortis was made out of aerospace-grade materials, with its armour consisting of aluminium, carbon-fibre, Kevlar and laminated titanium in its appearances in Series 1-3.
 
[[File:Mortis_official_image_2.png|thumb|Official image of Mortis in Series 2]]
After having its tracks exposed in Series 1, Mortis was rebuilt and redesigned for Series 2, featuring a revised front end and newer, more angular armour which enclosed its tracks completely. The robot also received a faster and more reliable axe mechanism, a new transmission, and other general improvements; its colour scheme also changed from black and dark grey in Series 1, to all-over grey for Series 2. In both series, Mortis's drive and weapon systems used DC motors salvaged from mobility scooters, weighing 6kg each and driven by second-hand wheelchair controllers.<ref name=RobKnight230219>Corrspondence between Rob Knight and [[User:VulcansHowl]], 23rd February 2019.</ref> 
[[File:Mortis3.JPG|thumb|left|The Series 3 incarnation of Mortis in the arena]]
For Series 3, Mortis received yet another rebuild, with only its chassis remaining unchanged. The most significant alteration was the addition of an electric lifting arm mounted beside the signature axe, which allowed the robot to lift 100kg and self-right. Other key upgrades included new tracks featuring injection-moulded pads, more streamlined armour plating, new internals and a filtered air supply. Additionally, the original DC drive and weapon systems were replaced with a lighter and more powerful system, incorporating brushless servo motors donated by Swiss company Infranor and a custom three-channel brushless driver built by new team member Ben Gordon. These new motors necessitated a redesign of Mortis's axe mechanism, in order to cope with the improved acceleration they offered.<ref name=RobKnight230219/> At 79.5kg, this incarnation of Mortis weighed slightly over the Heavyweight limit in Series 3. Mortis's armour and wedge were painted bronze-green and silver for Series 3 and its Series 4 War of Independence battle against [[Ghetto-bot]], which was later changed to black, bronze-green and light grey for the rest of the robot's appearances in Series 4. Also in Series 4, its armour was coated in silicon carbide, which when used as an abrasive, is almost as hard as diamond. This effectively made Mortis diamond-coated.

[[File:Mortischassis2.jpg|thumb|right|Mortis without its armour, at the time of Series 2]]
Like [[Firestorm]] in later series, Mortis remained roughly the same shape and design throughout the series, gradually being improved with more powerful motors, faster and more powerful weapon mechanisms, and what the team described as "better reliability". The axe and lifter combination it used in Series 3-4 was subsequently emulated by several other robots including [[Vercingetorix]] and its successor [[Comengetorix]], [[Hydra]], [[Oblark]],  [[Ripper (Featherweight)|Ripper]] and [[Hydrotec]]. However, while the tantō axe was effective and highly-regarded, Mortis regularly suffered from reliability issues with its tracks and weapon motors, which at one point resulted in the axe being converted into a ramming blade in Series 1. The robot itself also had a high ground clearance, and was vulnerable to having its tracks damaged by arena spikes/side bars in earlier series.