1940 – Walking SuperTank – Hutchinson and Smith (British)
This demonstration model was remotely controlled by means of flexible cables: the operator used one limb to control each leg.
The British firm W. H. Allen & Company, with A. C. Hutchinson and F. S. Smith, designed the first military related walking machine in 1940. The proposed armoured fighting machine in a partly engineered state.
Of the various leg designs and configurations considered, No 2 above was the chosen preference.
From Todd's book "Walking Machines"
The earliest serious attempt to build a walking machine with independently controlled legs was made in Britain in 1940 by A. C. Hutchinson and F. S. Smith (Hutchinson 1967). Hutchinson, who worked for W. H. Allen & Company Ltd, suggested that for a very large armoured vehicle, in the 1000 ton class, legs would be better than tracks. Hutchinson and Smith decided on four legs and the quadruped crawl gait. They studied a variety of leg mechanisms, mainly intended to allow a pair of hydraulic actuators to produce easily separable vertical and horizontal movement. They chose a design with a rolling thigh joint, which acted as a kind of inverted wheel, and a telescoping leg.
The proposed control mechanism consisted of a feedback loop per leg, with the four legs each being controlled by the hand or foot of the driver: essentially the solution to be adopted by General Electric for the Walking Truck in the 1960s.
Hutchinson and Smith built a four legged model, about 60cm high, whose eight joints were controlled by flexible cables which led to a console at which the operator sat, with his feet on the two hind-leg pedals and his hands on the two fore-leg handles. The model was made to walk and to climb over a pile of books. (Not surprisingly, in 1940 the UK War Department was not prepared to abandon its commitment to the well established tracked tank, and the project was halted.)
Be careful when interpreting this photo. The 'tiny' 12-ton tank mentioned in the caption is between the shovel and the tracks in the left-hand image. The right-hand image is the 1000-ton Supertank. The actual legs are largely hidden (protected) by the 6-inch steel plating. The 'overshoe' on the foot can be mis-interpreted as a caterpiller track, which it is not.
The proposed dimensions of the "walking fighting machine" is 42 feet long, 30 feet wide, and 18 feet high.
As an aside, its been suggested by others that the Star Wars Jawa Sandcrawler looks very similar to Hutchinson's "Super tank".
The above images are all from "Machines Can Walk" by Hutchinson, 1967 – see full pdf here.
For the researcher on this particular machine, the UK Archives have lots of other information – see here.