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Diplock Tractor with its Pedrials

1 - Four wheels drive Diplock Tractor, 1902, with its studs 'pedrials'. Pict from Revue des Engins 09/2002 by Francis Pierre issued from the book : In a century of Traction Engines published in 1959.

Fowler wheel with spring system

2 - Fowler wheel with spring system in 1870. Pict from Revue des Engins 09/2002 by Francis Pierre.

Spring wheel seen at Sinsheim Museum

3 - Spring wheel for agricultural tractor seen in 2000 at the Sinsheim Museum, Germany. Pict J M M.

4 - Spring wheels in 1943 of the Meili tractors

4 - Spring wheels in 1943 of the Meili firm tractors at Schaffhausen then Schübelbach, Switzerland, answered rather the shortage of rubber.

 Picture from book of Gerold Röthlin ‘From Autotractor to modern special vehicles’ from Verlag Gerold Röthlin, Kriens, 2004.

Spring-wheel for all-terrain vehicle

5 - A spring-wheel for all-terrain vehicle is submitted late to the Motor Show 1950. Pict of review l'Automobile, N° 54, Oct 1950, Special 'Salon de Paris', on Picassaweb.

Grumman MOLAB Rover

6 - The Grumman MOLAB of 1964 consists of two watertight modules suspended on leaf springs as spokes ofwheels. From

The Grumman with deformable conical wheels

7 - The Grumman in 1965 with strange deformable conical wheels surrounded by flexible strips.

The Bendix Rover

8 - The Bendix 1969 weighs about 800 kg for 8.4 m long. The steel tires are 2 m in diameter, its titanium rings involved the suspension together with a rod connected to a torsion bar. An electric motor was attached to each wheel. Pict from the review 'L'Auto Journal', 9 April 1970.


9 - The lattice wheel, studied and calculated by Mieczyslaw Gregory Bekker, the father of Theory of Off-road Locomotion in the laboratories of General Motors in Santa Barbara, California, in the 60s. It was chosen for the 4WD Lunar Roving Vehicle by Boeing (GM), which landed on the moon. Pictured, M. G. Bekker is sitting in the middle, Sam Romano, standing, Ferenc Pavlics, probably early 80s. A prototype of Boeing 6x6 articulated wire wheeled had been built in earlier stages. Pict from the collection of Jean Rémus, former member of ISTVS.

Robot wheels of Company VNII Transmash of St Petersburg.

10 - Robot wheels of Company VNII Transmash of St Petersburg.

The Tweel of  Michelin

11 - The Tweel of Michelin tested in 2006 in South Carolina and adapted on wheeled loader. Pict from Michelin in site

Tolotti & Pavesi tractor , Milan, P4 model 1925 

12 - Rear view of an articulated Tolotti & Pavesi tractor, Milan, P4 model 1925, with solid tires and foldable spikes, seen in Sinsheim in 2000. Pict J M Maclou.

Phoenix and Buckeye tractor with retractable spikes

13 - Tractor Phoenix and Buckeye in 1916, with an average extra traction by retractable spikes.

 Picture from book of Fred Crismon ‘US Military Wheeled Vehicles’, Crestline Publishing (Motorbook), 1983.

Rubbertrax unbreakable solid tires wheels

14 - 'Rubbertrax' unbreakable solid tires wheels. From flat-proof-tires site

LeTourneau L-2350 loader

15 - LeTourneau L-2350 loader, with 4 m in diameter and 1.8 m wide tires. The mass of the tire alone was 6.8 t. The rim and the chain of protection were more. Huge !

Best Tractor Manufacturing Co

16 - Best Tractor Manufacturing Co in 1900. The wide wheels reduced ground pressure but congestion becomes maximum. Overall width requires a triangulation of maintenance. The tractor got stuck in bogs and extract has not been an easy task. Pict from Journal of Teramechanics, June 1979.

Rolligon 4450 of National Oilwell Varco Inc

17 - Rolligon 4450 of Rolligon Corporation itself purchased in 2006 by National Oilwell Varco Inc., Houston, Texas.

CATCO, Alaska, still employs Bechtel vehicles

18 - The transport company CATCO, Alaska, still employs Bechtel vehicles of the 70's rebuilt among others by Rimpull. Pict from site flikr.

MVTOu-2 with low pressure tires

19 - MVTOu-2 in 1958. The Russians were not far behind. Pict from 'Les Véhicules tout terrain' Tome I by Alain Dupouy, Grenoble, 1995.

Barreiros Truck TT-90 with 'Lypsoïd' tires

20 - Barreiros Truck, TT-90 from 1958 restored in 2008, equipped with 'Lypsoïd' tires. Pict from, which is no more in line.

Gas Truck 66 equipped of tire-hoops

21 - Gas Truck 66 equipped of tire-hoops, similar to the Lypsoïd tires. Pict

Wilco Marshes Buggies & Dragline, Inc., Louisiana

22 - Amphibious craft with wheels,   Quality Marsh brand, now Wilco Marshes Buggies & Dragline, Inc., Louisiana. Pict from the good site

amphibious buggy manufactured by AMG, St Gaudens

23 - Hydrostatic transmission amphibious buggy manufactured by AMG, St Gaudens, until the 80's. Weighing a total of 13 t, 2 t payload, it was powered by a Deutz 160 hp engine with wheels of 2.96 m diameter and 1.5 m wide. Speed of 8 km / h on land and 5 in water. It included an anchor into the ground by four rods to counter air turbulence caused by landing a helicopter on its platform. Today, the wheeled buggies are replaced by tracked vehicles. Pict from a brochure of AMG, J M M collection.


Tree-Crusher of LeTourneau G-80

24 - Tree-Crusher of LeTourneau launched in the early 60's. The G-80 measured 15 m long for 475 hp and 65 t, had electric transmission and a direction by joint. He overthrew the trees with its front bar, crushed and sank the branches in the ground with his metal rollers. The only known survivor, a G-175, is located in Mc Kenzie, British Columbia, Canada. Pict from LeTourneau brochure, J M M collection

the 'Swamp Thing' of the manufacturer Paul Wever

25 - Since the early 2000 exists the 'Swamp Thing' of the manufacturer Paul Wever Construction Equipment, Illinois, prototype with 8 large rollers for wetlands, for a logging company in Georgia. This 'Swamp Thing' weighs 90 ton on hard ground and 45 t maximum on water. It can be radio controlled up to 60 m. Pict from

Russians studied in the 60’s tire rolled pipeline carrier

26 - It seems that Russians studied in the 60's tire rolled pipeline carrier, at least in scale model. Pict from 'Les Véhicules tout terrain' Tome I by Alain Dupouy, Grenoble, 1995.


The 6x6 robot Marsokhod  of VNII Transmash

27 - The 6x6 robot Marsokhod is fully articulated in pitch, roll and yaw. Robot for Mars Exploration, tested in the United States and France (known as LAMA) but designed in St. Petersburg, Russia, by VNII Transmash in the early 90's, it includes bevel wheels ending a cylinder fitted with spikes. A copy is currently on display at the Musée des Arts et Métiers in Paris and this robot is now marketed.

The inflatable floating wheels of Nicolas Straussler

28 - The floating wheels made of large inflatable cylinders adapted by Nicolas Straussler in the 50's on a Jeep allow it to move in water. Pict from Wheels and Tracks N° 44, 1993.

Rotoped of Julius Makerle

29 - Rotoped of Julius Makerle. Although this picture is a reproduction of a drawing, this machine really existed. Pict Popular Science, Jan 1970.

The system Rotoped was simple


 30 - The Rotoped system was simple : the ball in front of the wheel emptied while the back one swelled with valves. The wheel moved forward by gravity. Pict Popular Science Jan 1970.

The M7 tractor with elliptical wheels

31 - The M7 tractor from Allis Chalmers, normally fitted with tracks to the rear wheels equipped with elliptical wheels for testing.

O. A. Goulden undertook tests on scaled model

32 - O. A. Goulden also undertook tests on scaled model. Pict from Revue Générale du Caoutchouc, Nov 1955, J M M collection.

elliptical wheels with Meccano

33 - 'Meccano' construction set lends itself well to this kind of achievement seen in 1998 at an exhibition at the Porte de Versailles in Paris. Pict J M M.

Square wheels patent

34 and 35 - Square wheels, whose patents have been found on the Internet, show that a practical implementation would be too complex compared to the advantage gained : crossing obstacles. Pict from Popular Mechanics, Apr 1970.

Square wheel patent


34 and 35 - Square wheels, whose patents were found on the Internet, show that a practical implementation would be too complex compared to the advantage gained. From Google patent.

Square wheled bicycle

36 - A bicycle with square wheels, of course, but with a special road !

Car with curvilinear triangle wheel-shaped

37 - Car with curvilinear triangle wheel-shaped, an original idea but rather theoretical. Google patent : us002790503-001 patent of Kopczynski, 1967

Half-wheels patent

38 - Half-wheels, 1999 patent. A prototype could be built ! Horizontality warranted on roads through the gap of half-wheels at 180 °. Google patent. us005881831, 1999

1 / 3 wheel patent off road vehicle

39 - Here they are 1 / 3 wheel offset and juxtaposed on the width and length of the vehicle. On the road, the vehicle is running smoothly horizontally. To try ! Google patent : us07128175 in 2006

Off road Running legs Russian vehicle

40 - Running legs Russian vehicle. This is a drawing but no doubts that concrete realization would bring new in off-road locomotion. It is similar to Whegs, at the end of this chapter. Pict from the book of Alain Dupouy 'Les Véhicules tout terrain, Tome I', Alain Dupouy, auto-editeur, Grenoble,1995.

Rhino Amphibious vehicle

41 - Rhino had good amphibian qualities. Pict of Life Archives.

Rhino amphibious vehicle

42 - View from the front of the Rhino : it looks like a monster ! Pict of Life Archives

Rhino amphibious vehicle

43 - Bottom view of Rhino. The center of gravity positioned very low and hemispherical wheels were preventing to rollover. What was it in reality ? It is doubtful as the ground path is narrow. Pict Popular Science, 1954.

wheelbarrow with low pressure spherical wheel

44 - The low-pressure spherical wheel swallows obstacles, even on a wheelbarrow. From

- Terrastar of Lockheed Aircraft Service Company

45 - Terrastar in 1967 from the Lockheed Aircraft Service Company, Sunnyvale, California, a subsidiary of Lockheed. At the time, aircraft manufacturers were often diversified in all-terrain vehicles. Pict from Lockheed, J M M collection.

Landmaster of Dan Jeffries

46 - Landmaster : it can be seen in action in the movie of 1974 : 'Damnation Alley'. The site of Dan Jeffries shows us the father of this extraordinary vehicle and other achievements. http://www.

chassis of the Landmaster

47 - The chassis of the Landmaster is in two parts. The Landmaster steers by articulation unlike the rigid Terrastar skid steers. Pict from J M M collection.

Gato Arana Car show of Barcelona 1972

48 - The ‘Gato Arana' seen at the Motor Show of Barcelona in 1972. He could climb steps of 1 m by using rotors. On the other side, it seems that the minor wheels were fixed on the rotors. Jóse Artes de Arcos, 1893-1985, important car Spanish industrial of ‘Fabrica de Accesorios para Automobiles y Motocycletas', Barcelona, built in 1971 the amphibian 6x6 ‘El Gato Montes' and this one that looks like a little Terrastar. Does it still exists  ?


patent of a star wheeled vehicle

49 - 1965 patent of a star wheeled vehicle with 6 minor wheels by rotors. Times were favorable to little unbridled ideas and achievements that arose. Genuine innovations spread through different areas. us3208544.

'Meccano’ model of a star wheeled vehicle

50 - 'Meccano' model of a star wheeled vehicle seen in an exhibition at the Porte de Versailles in Paris in 1998. Pict from J M M.

 Whegs robot with wheels like legs

51 - Whegs : amid pitch articulation  promotes crossings.

Whegs 2nd generation

52 - Whegs 2nd generation whose 'legs' contain portions of rims.

Whegs Impass

53 and 54 - Whegs Impass : we can see the sliding rays automatically adaptable to the terrain. The mechanism must be sealed for outdoor use but the practical implementation must be delicate.



Whegs Impass  

53 and 54 - Whegs Impass : they can see the sliding rays automatically adaptable to the terrain. The mechanism must be sealed for outdoor use and the practical implementation must be delicate.

Asguard II of the University of Bremen

55 - The University of Bremen also built, among other things, Whegs : it can be seen the robot Asguard II on the impressive obstacles trail in the Centre of Robotic Innovation.

Rhex of Boston Dynamics

56 - Rhex of Boston Dynamics. By programming differently rotation of the legs, it is possible to replicate the rapid march of the dogs, back somersaults and swimming in water.

Toolkit of DRDC Suffield and Cillineo

57 - The Collineo Company, Drummondville, Quebec, a service company helping high-tech industries in the areas of civil protection and field operations, creates all-terrain robots such as micro-hydraulic reconfigurable Toolkit 4 or 6 wheels, in collaboration with DRDC Suffield (Defence R & D Canada). It includes suspension arm in two parts and 14 degrees of freedom with electric motors or hydraulic units. These arms can best bridge and climb the difficult slopes by reducing the action of the wheels at the expense of arms that mimic walking : the center of gravity moves (inching system or peristaltic mode) without wheels. The robot Hylos of the Institute for Intelligent Systems and Robotics, Paris, and Work Parter of Helsinki University, Finland had also articulated arms with wheels so that the articulated 6x6 Marsokhod robot originally studied in Saint Petersburg by the Company Transmash had an expandable frame (but no legs) that allowed him to accompany action of the wheels.,en/




After a few changes over the centuries, the wheel, invented more than 5000 years ago, only really began to evolve at the 19th and 20th centuries. The roads, long little passable, and development of mechanical traction stimulated inventors whose ideas were sometimes eccentric.

1 - Metal spring wheels  :

The first spring wheel patent, from 1835, seems to be the one of William Adams :

In 1902, Taskers built a steam engine with four-wheel drive and steering, already uncommon machine  at the time, the Diplock (photo 1). In addition, he fitted its wheels with articulated studs 'Pedrial' that would allow a better distribution of the mass of the craft on the ground and a better crossing. In fact, the vessel would run very slowly to avoid zigzagging.

They invented later, in parallel with the tires that will prevail in the 30s, springs wheels : they can see, among others, the Fowler wheel (photo 2) for steam tractor with a spring system and deformable steel rim, which did not give satisfactory results.

There were many spring wheels prototypes (photo 3 to 5).

The idea of flexible wheels this time in titanium was incorporated into the 60's on some prototypes of sophisticated lunar vehicles, rubber becoming brittle at low temperatures and air rarefied. These were : Grumman MOLAB (photo 6), Grumman LRV (photo 7), Bendix (photo 8), Boeing 4x4 which ran on moon (photo 9) with wire wheels, so that a Russian robot of VNII Transmash (photo 10).
Today and after a long eclipse, the metal wheel comes back with Michelin's Tweel (photo 11).

2 - Solid narrow tires conventional wheels and inflatable tires :

The full-tread narrow tires were widely used before the 30s (photo 12).
Spikes foldable or collapsible (photo 13) or wheel cages helped traction.

The tread wheels, longtime dropped, come back on the market for about fifteen years in construction equipment. The wheel 'Rubbertrax' is a representative of this category (photo 14).

Tires established themselves in the 30's. These, Firestone trademark, the largest in the world are assembled here on the Letourneau loader L-2350 (photo 15).

3 - Wide wheels :

In the absence of tracks in 1900, Best Manufacturing Company produced this heavy steam tractor (photo 16) with two rear drive wheels for operating in the peat of the Sacramento Valley : the basic wheel 2.8 m diameter was surrounded by wooden bars of 4.7 m wide. It was not looking then the reliability or very good traction. At the same time, they invented the crossbar straight, diagonal or chevron.

The wide wheels experienced a modern version in the 50s, known as the Rolligon (photo 17) (see article on Rolligons) built by William Albee of Carmel, California. Today, the Catco, huge trucks of Bechtel trademark (18 photos) and equipped of Rolligons to preserve soils furrow the North Slope in Alaska for the oil industry. The Terra-tires are corollaries of them narrower and more resistant from Goodyear, the first to manufacture them.

The Russians have tested the rolls-tires on various models from 1958 (photo 19), tests not followed of series.

The tires 'Lypsoïd' (photo 20) invented by Nicolas Straussler at the same time were also very large but without sides. In Russia, there are always the same types of tires (photo 21).

The caisson wheels are also used (photos 22 to 28)

4 - Rotoped of Julius Makerle :

The Rotoped (photos 29 and 30) whose prototype was built in 1964 by the Institute of Automotive Research in Czechoslovakia, had 4 wheels. They were fitted with balloons that were inflated and deflated through a valve system on a circuit compressed air : a deflated balloon before the wheel while the other was swelling at the back which allowed the vehicle to move by gravity. As there was no driving force, the wheels could not skate.

The absence of drive shafts allowed each wheel to move 180 ° and the vehicle could move perpendicular to its original path or crab. The top speed was 20 km/h and the maximum slope reached 20 degrees. An assisted steering completed the set.

The inventor, Julius Mackerle, was director of motorization in Tatra until 1958 and then became director of the Institute mentioned above. He thought at the time using his system for locomotion on Moon where the gravity lower than on Earth reduces the adherence of a classical wheel based on friction. The lack of atmosphere on the Moon would reduce the inflation pressure of the system so the required power and mass.

5 - Elliptical wheels and others :

A snow crawler tractor Allis Chalmers M7 was transformed with ellipse shaped wheel (photo 31) and tested in 1946 : the wheels were no longer skating by turning on themselves, but one must penetrate and serve of anchor while the other, flat, had to bear the weight of the vehicle. The pulling force would be doubled. A balance between the 2 wheels chocked to 90 ° allowed to maintain the horizontality of the whole. Nevertheless, this prototype did not give satisfaction in the mud (but width of 'wheels' was small), vibrated a lot on road and was abandoned. Photo 31, taken in 1950, reappeared recently after the photos archives of LIFE magazine was online.

John F. Kopczynski, graduated from the Rochester Institute of Technology, took numerous patents on the elliptical wheel from 1940 (they are available on the U.S. patent site). The idea of the M7 prototype vehicle came well from him. He nevertheless continued his research in this area.

The scale model tests, conducted in 1949 in the mud showed, according him, that these elliptical wheels did not slip and did not turn on themselves. The model was traveling at 40 km/h without vibration.

J. Kopczynski took 80 patents during his life and not just the wheels.
He became president of Ascension Industries in North Tonawanda, New York, a major metalworking at the same time as mayor of this town. He died in 2005.

Osmund Anthony Goulden of Sunbury-on-Thames, Middlesex, also patented the oval wheel in 1961 after testing model as well (photo 32) dating from 1955. This model 'Meccano' (photo 33) was seen in 1998.

The theoretical inventions being limitless, patents with square wheels were also expected to increase traction, made their appearance (photos 34 and 35). There are no known practical implementation except a bicycle (photo 36) with square wheels and special road.
Another idea patented by J. Kopczynsky in 1987 was to replace the circular wheel of a vehicle by curvilinear triangle shaped wheel (photo 37) with the same theoretical advantages as the oval wheel. The upper part drove the triangular wheels by friction. The vehicle must remain horizontal on flat ground with the properties of the curvilinear triangle.

Similarly, the invention of semi-wheels (photos 38 and 39) appeared in several patents. These half-wheels were able to roll horizontally on flat ground and a better 'hook' in difficult terrain. They joined a little current 'Whegs' and 'Rhex' (see Chapter 9) whose discontinuous or missing rims wheels promote difficult progression.

The Russian model with 'legged' wheels (photo 40) was within the same idea discontinuous rims.

6 - Hemispherical wheels and 'Rhino' or 'Polywog'.

The publication 'Popular Science' of September 1943 described an amphibious vehicle, "The Roller" with two large hemispherical wheels, capable of going anywhere and replacing the track.

It was not until 1954 that a prototype (photos 41 to 43) was commissioned by Elie P. Aghnides at the Marmon-Herrington Company of Indianapolis, Indiana. Engineers of Marmon-Herrington stretched the vehicle relative to the initial request of E. P. Aghnides for stability matter. The two large front half-spheres, V mounted, contained strips of rubber for traction. The low center of gravity and the shape of wheels should prevent it to overturn.
The small rear drive wagon steered wheel also steered the vehicle. A hydrojet swiveling 360° mounted between the wheels allowed it to move easily in water. It weighed 4.5 t and its Ford 6-cylinder engine of 130 hp theoretically allowed 75 km / h. Its behavior in difficult terrain, mud in particular, proved excellent despite the lack of suspension.
A smaller version was also built by Marmon-Herrington.

But who was that Mr. Elie P. Aghnides, inventor and owner of the so original 'Rhino'  ?

This Greek-born engineer living in New-York invented, as revealed in Life magazine of August 5, 1946, a new mechanism for mixing air with water jets in the domestic water as showers and sinks and break the jets. This enabled him to earn enough money to build the 'Rhino', the big and small. He caused and had to undergo several lawsuits related to its patents on mixing with water. He sued in 1972 Marmon-Herrington Company for non-compliance and not informing the complainant about a contract to build a revolutionary vehicle equipped with 2 aligned hemispherical wheels, the 'Cyclops'. He won the case the result was for him by the recovery of $ 120,505.40. Too bad the 'Cyclops' was never built ! Elie P. Aghnides died in New York in the early 80s.

They can see the sites :

and wonder if this prototype does not become fashionable on the Internet, at least for the specialists.

What happened to the two prototypes ?

Both versions of Rhino stationed at Marmon-Herrinton in Indianapolis in the early 60's but the company moved to Knoxville, Tennessee. The 'smaller' was then destroyed when the 'Rhino' was bought by Eugene Pock and Sons Inc. of Zionville, Indiana, who preserved and presented every year thereafter the second weekend of August to Mid America Threshing and Antique Show in Tipton, Indiana. However no pictures of these events with the Rhino reached us and no further communication or publication was emerged over the last twenty years. From there to say it had been scrapped, there was only one step.

After much research, emails and telephone calls without success, and even the contact of Don Shew, official historian of Marmon-Herrington, the author was recently confirmed that the vehicle was just in Lebanon, Indiana in Eugene Pock Jr. who restores it. It will certainly emerge one day.

It would have been a pity not being able to admire this strange specimen of the American dream of the 50's released in the press and newsreels (visit the Gaumont archives site) and then able to dream of many young people in many countries. Today, became older, they can through the Internet to trace the fabulous gear.

7 - Spherical wheels

In this section, finished motor vehicles but long live the wheelbarrow : its low pressure spherical wheel (photo 44) allows it to roll smoothly over bumps, much like the Rolligon. Another wheel deformable ribbon shaped fitted on a wheelbarrow seen in the 'Book of Inventions' allows the same thing.

8 - Star wheels and the 'Terrastar'

The idea is old and star wheeled carts are still rising stairs. Still, Robert W. Forsyth and John P. Forsyth of Lockheed Aircraft Service Company of Sunnyvale, California, built in 1967 the Terrastar (photo 45), stairs climbing vehicle but behaved better in mud than on rocky terrain. The craft was amphibious where, thanks to its large rotors, it was going well in water (12 km/h) but his favorite field was deep mud in which it excelled. On the main road, rotors were fixed and the 12 wheels 8 of them in contact with the ground, turned on themselves and propelled the vehicle at 55 km / h. Its was skidd steered. Unfortunately, some complexity of the craft may have played against it and also a small payload compared to its mass : 1120 kg empty and 1635 kg full load.

The Terrastar is now stored outdoors for several decades at Waterways Experiment Station in Vicksburg, Mississippi.

Dan Jeffries, coachbuilder in Hollywood, returned to the same concept in creating the Landmaster, one of the stars of the film 'Damnation Alley' in 1974. He appeared in television series before being completely restored in 2007 (photo 46). The vehicle steered by articulation (Photo 47), unlike Terrastar.

We could see at the auto show from Barcelona in 1972 a similar small craft the 'Gato Arena' (photo 48) and identify numerous patents on the principle of the star wheel (photo 49). Evidence that the principle is known, 'Meccano' models were built (photo 50).

9 - Whegs and Rhex robots

What means Whegs ? Simply 'Wheels' and 'Legs'.
Whegs Robots (photo 51), very current, of University of Case Western Reserve in Cleveland, Ohio, uses legs that roll like wheels. The result is spectacular : nothing seems to stop these little robots whose several versions exist, the later having beginnings of rims connected to the arm (Photo 52).

The Wheg Impass (photos 53 and 54) also includes an even system of sliding shelves that allow more possibilities.

University of Bremen also builds very impressive Whegs : the Asguard (photo 55).

The Rhex (photo 55), designed on the same idea by five American famous Universties including one of Cargenie Mellon, Pittsburgh, Pennsylvania, is now marketed by Boston Dynamics, Waltham, Massachuchetts. The rocks do not scare it and if it overturns, it can quickly get back on its feet and continue its travel. Again, several versions exist with different arms or even amphibious versions where the arms act as fins.

The Toolkit (photo 57) of Collineo and DRDC (Defence R & D Canada) has legs in two parts.