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Pat Rawlings’ Rendering of the “Habot” Mobile Lunar Base Concept (courtesy of John Mankins, NASA HQ, and Neville Marzwell, Jet Propulsion Laboratory).

Mankins’ Habot
John Mankins introduced the Habitat Robot concept, “Habot,” in 2000 as a radical departure from traditional lunar base studies. The strongest attribute of the Habot is its “small is beautiful” emphasis. The Habot modules land on six articulated legs, and then takes double advantage of the legs by using them to walk away robotically from the landing zone. The pressure vessels are hexagonal insofar as they require three cross-axes separated equally at 60°of arc. They cluster together automatically to form a temporary base. The possible module size ranges from about 3 to 5m diameter. The crew arrive and depart the surface of the moon in a separate Descent/Ascent vehicle that may share some hardware commonality with the Habot units, but is optimized for transporting the crew through cislunar space, landing and taking off from the lunar surface. With self-ambulating lunar base modules, it would be feasible to have each module separate itself from its retro-rocket thruster unit, and walk five to ten km away from the LZ to a pre-selected site. These walking modules can operate in an autonomous or teleoperated mode to navigate the lunar surface. At the site of the base, the walking modules can combine together; make pressure port connections among themselves, to create a multi-module pressurized lunar base. FIGURE 2 presents an artist’s rendering of the Habot concept, showing both a hexagonal Habot cluster base, and Habot rovers moving about the lunar surface, driven by astronauts. A peculiar power source appears in the form of the cylinders mounted atop each Habot, which mount photovoltaic cells to provide power during the 14 sol lunar day. With exposed joints, the articulated legs would be vulnerable to dust and grit in the mechanisms, so the legs would need to be covered with dust-tight “stockings”.

“WAGON TRAIN” CONCEPTS
The “Wagon Train” was an American pioneering technique in which a group of ox-drawn onestoga wagons traveled together in line. When they stopped for the night, they would “circle the wagons” to form a temporary base cluster. The Habot concepts draw upon various aspects of the wagon train paradigm.

Habot
Source: Encyclopedia Astronautica

Habot, manned lunar rover. Study 2000. The Habot (Habitat Robot) modules would land on six articulated legs, which also provided the locomotion. These walking modules could operate autonomously or in a teleoperation mode.
The modules could be combined to form a multi-module pressurized lunar base.

Each module was up to 5 m diameter with a mass of 10 metric tons. The pressure vessels had hexagonal shapes to allow clustering with other units. Photovoltaic cells on the top of the modules produced the power required during the lunar day (14 earth days). Movement would only be conducted during the lunar day. The units would cluster and remain stationary at minimum power levels for the lunar nights. A crew of 6, using several Habot units, could be accommodated on a 100 day lunar mission.

Characteristics

Crew Size: 6.

Gross mass: 10,000 kg (22,000 lb).
Height: 5.00 m (16.40 ft).
Diameter: 5.00 m (16.40 ft).

Bibliography
Zakrajsek, James J; McKissock, David B; Woytach, Jeffrey M; Zakrajsek, June F; Oswald, Fred B; McEntire, Kelly J; Hill, Gerald M; Abel, P; Exploration Rover Concepts and Development Challenges, NASA/TM-2005-213555 / AIAA-2005-2525, March 2005.

Patent number: 491927
Filing date: Apr 8, 1892
Issue date: Feb 1893.  See full patent here.

Rygg Horse Pat 1893, filed 1892.  No model. Cannot find any evidence that it was actually built.

Brunton's Traveller was constructed by the Butterley Company in Derbyshire in 1813 by William Brunton (1777–1851). Also known as the "Steam Horse" it had a pair of mechanical legs, with feet that gripped the rails at the rear of the engine to push it forwards at about three miles an hour.

THE LIFE AND TIMES OF SIR GOLDSWORTHY GURNEY
Chapter 5: INVENTING THE STEAM CARRIAGE    p77

In 1824 David Gordon tried again with "an arrangement of machinery, by which an action similar to horses' feet could be obtained." Six jointed iron legs, fitted with feet, were connected by brass joints, straps, and keys to a set of cranks, propelled by a pair of steam engines. The legs extended through the floor in the middle of the carriage, analogous to the legs of a horse, and the feet pushed backwards on the road to move the carriage forward. This astonishing arrangement had been tried by other inventors before Gordon. It was regarded as quite promising despite its ungainly, clattering features. After Gordon applied to Gurney for permission to use one of his light tubular boilers, Gurney adapted Gordon's machinery for his own carriage, constructing a set of smaller legs to be used as supplementary traction when going up hills. The legs, or "propellers," were attached to parallel wooden blocks that slid back and forth in metal grooves, in alternate strokes, underneath the carriage. In his first experiment with a full-size carriage, Gurney used the propellers to ascend Windmill Hill. He found them inconvenient and heavy, but still believed they were necessary for the purpose. Indeed, several scientific journals had just published papers demonstrating that "fact" with mathematical formulas. However, "after much thought and experiment," as Gordon reported it, Gurney devised a mechanism that would bring the propellers into action only when the wheels slipped. With this in place, he launched a second run of nine and a half miles between his Oxford Street factory and Edgware. Much to his surprise, the ordinary carriage wheels maintained excellent traction, even when going up considerable inclines. The whole phenomenon of slippage, he discovered, resulted from the sudden impact on wheels by the large cylinders of older high-pressure engines. Because his locomotive increased steam pressure gradually by means of a throttle, it eliminated the shock. Gurney apparently kept the propellers for a while, expecting that they would be necessary in case of mud or snow, but after several more trials, they were abandoned. In later evidence before Parliament, he claimed that he had used his carriage on both snow and ice, with few problems." After the Windmill Hill—Edgware trials, the rear carriage wheels were driven by a crankshaft attached directly to the dual pistons of the engine, and in fact, power was commonly directed to only one wheel at a time. Although hundreds of people witnessed these trials, and although they were reported in the local press, some mechanics still refused to believe the results. One of these was John Farey (17911851), a civil engineer experienced with steam engines, who had prepared the drawings for Gurney's original "propeller" patent. Farey evidently changed his mind, because he later adapted the Gurney design to a steam carriage of his own.
The steam for Gurney's first carriage was generated by a large drum boiler, common to most engines at that time. The design had two drawbacks, which he and other inventors worked to overcome. First, the boiler was heavy, especially when filled with water. It added significantly to the weight oi the carriage and ate up its own energy in moving forward. This was not a problem on rails, which reduced friction to negligible proportions, but it proved impossible on gravel roads. Second, the boiler was likely to explode. As hot water rose in the boiler, cold water descended along unpredictable pathways. Heat and cold, water and steam were often distributed unevenly around the inside of the boiler, causing "hot spots" to form and burst. Also, the evaporation of the steam left a residue, or crust, called fur, which collected near the bottom of the boiler where the flame struck its surface. The fur caused further irregular heating and eventually ate through the metal. Filtering the water did not solve this problem; the residue was chemically dissolved in the water to start with, and, after it was deposited, it could not be removed except with hammer and chisel or a rough rake. Moreover, Gurney had discovered in the course of his chemistry research that small amounts of water in a hot boiler actually decomposed. Combining with nitrogen in the atmosphere, they formed new, highly volatile compounds. Most inventors of the time simply ignored the problem of safety. They aimed to reduce the weight of the boiler, hoping, as Alexander Gordon acidly commented, that the skill of the engineer, or sheer luck, would prevent explosions, or that if one occurred, it would be "attended by death only to some of those whose situation could be supplied on the morrow at equally low wages."

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IMPROVEMENT IN TRACTION-ENGINES
 JOHN E. PRAUL
Patent number: 221354
Filing date: Sep 26, 1879
Issue date: Nov 4, 1879. See patent here.