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The purpose of this paper is to evaluate the locomotion performance of all‐terrain rovers employing rocker‐type suspension system.

In this paper, a robot with advanced mobility features is presented and its locomotion performance is evaluated, following an analytical approach via extensive simulations. The vehicle features an independently controlled four‐wheel‐drive/4‐wheel‐steer architecture and it also employs a passive rocker‐type suspension system that improves the ability to traverse uneven terrain. An overview of modeling techniques for rover‐like vehicles is introduced. First, a method for formulating a kinematic model of an articulated vehicle is presented. Next, a method for expressing a quasi‐static model of forces acting on the robot is described. A modified rocker‐type suspension is also proposed that enables wheel camber change, allowing each wheel to keep an upright posture as the suspension conforms to ground unevenness.

The proposed models can be used to assess the locomotion performance of a mobile robot on rough‐terrain for design, control and path planning purposes. The advantage of the rocker‐type suspension over conventional spring‐type counterparts is demonstrated. The variable camber suspension is shown to be effective in improving a robot's traction and climbing ability.

The paper can be of great value when studying and optimizing the locomotion performance of mobile robots on rough terrain. These models can be used as a basis for advanced design, control and motion planning.

The paper describes an analytical approach for the study of the mobility characteristics of vehicles endowed with articulated suspension systems. A variable camber mechanism is also presented.

Wheel‐terrain interaction has hardly been taken into consideration in the process of conventional mobile robot design, but its importance has been reflected increasingly towards these categories of mobile robots in rough sandy terrain or obstacle‐dense ground, as the first performance index in this situation is the trafficability of robot whose propulsion is uniquely generated by wheel‐terrain interaction. Consequently, it is valuable to find an optimized design method when the terrain and robot itself are regarded simultaneously. The purpose of this paper is to present a novel and reasonable design approach to mobile robot in sandy terrain.

Leading to some conflicted performance indices of robot, terramechanics describes the non‐linear characteristics in wheel‐terrain interaction mathematically, therefore, trade‐offs must be implemented to get a proper solution by multi‐objective optimization (MOO). In this paper, a five‐wheeled drive and five‐wheeled steering (5WD5WS) reconfigurable mobile robot is taken as demonstration with taxonomy of total‐symmetrical, partial‐symmetrical and asymmetrical prototypes. After function modeling, the MOO is carried out via iSIGHT‐FD using NCGA (Neighborhood Cultivation Genetic Algorithm) to minimize the mass, wheel resistance and maximize the static stability simultaneously.

After MOO, a compact and light weighted asymmetrical prototype is obtained with better trafficability, and other prototypes can produce diversified configurations to meet specific requirements. Significantly reduced masses (about 17 kg) enhance the grade‐ability when robot is in rough terrain. Performed real‐world experiments have also verified these prototypes.

The paper presents a new design approach for a mobile robot which focuses on both robot and terrain simultaneously with respect to conflicted factors. To unveil the insight relation of these factors, MOO is an effective tool to get a trade‐offs prototype.

An aeroplane adapted to remain controllable at low speeds and high angles of incidence has automatically moving slot‐forming planes along the leading edge of each wing, camber‐varying flaps at the trailing edge interconnected to the stabilising plane and capable of being locked by the pilot in various positions, and additional normally closed slots at the wing tips which open only when the main slots are open and the usual ailerons are depressed. The slot closing element connected to each aileron may also project above the upper surface of the wing to break up the air stream on that side of the machine on which for the time being the aileron is raised. These features are shown applied to a low‐wing monoplane with widely spaced landing wheels. Slot‐forming planes 35, Fig. 4, are carried by curved tubes 40 moving between guide rollers 41 carried by brackets on the front spar of the plane. They normally nest against the leading edge of the plane and move forwards automatically as the stalling angle is approached. Camber varying flaps 29, Figs. 4 and 9, and ailerons 28, Fig. 5, are pivoted to the trailing edge of the wing and have their forward edges so shaped that slots 47 are formed when the flaps or ailerons are depressed, the slots being substantially closed in the neutral and raised positions of the flaps and ailerons. The flaps 29 are interconnected to the stabilising plane 26, the leading edge of which is raised and lowered by links 55, and both are moved simultaneously by a lever 33 provided with a detent engaging with a locking quadrant 51. The air pressure on the plane 26 partially balances that on the flaps as regards their reaction on the lever 33. A rod 53 which actuates the plane 26 is connected to a lever 33a, Fig. 10, and the lever 33 has a quadrant 59 to which the flap cables are connected, the two levers 33, 33a being adjustably connected by screw‐and‐nut mechanism 34 in order to vary the relative adjustment of the stabiliser plane and flaps. At the forward edge of each wing tip opposite each aileron a slot 37, Fig. 5, is formed, which is normally closed at its lower end by a plate 63 connected by a lost‐motion link 64 to the slot‐forming plane 35, and at its upper end by a pivoted quadrant 67 connected to the corresponding aileron by a lost‐motion device 70. When the aileron is depressed, or raised beyond a certain amount, the quadrant is respectively withdrawn into the plane to open the slot or projected beyond the upper surface to disturb the streamline flow and reduce the lift on that wing tip. Springs 71, 72 normally centre the quadrant 67. The plate 63 only moves to open the slot 37 when the main slot is open. The wing spars 88, 89, Fig. 12, are connected to the lower edge of the fuselage and braced to the upper edge by struts 90, 91 with intermediate braces 92, 93, The rear struts 91 may be upwardly arched. The landing wheel axles are carried by hinged struts 95 and supported from the front spars by telescopic struts 96 with shock‐absorbers 82.

The purpose of this paper was to solve the shortage of carrying energy in probing robot and make full use of wind resources in the Antarctic expedition by designing a four-wheel land-yacht. Land-yacht is a new kind of mobile robot powered by the wind using a sail. The mathematical model and trajectory of the land-yacht are presented in this paper.

The mechanism analysis method and experimental modeling method are used to establish a dual-input and dual-output mathematical model for the motion of land-yacht. First, the land-yacht’s model structure is obtained by using mechanism analysis. Then, the models of steering gear, servomotors and force of wing sail are analyzed and validated. Finally, the motion of land-yacht is simulated according to the mathematical model.

The mathematical model is used to analyze linear motion and steering motion. Compared with the simulation results and the actual experimental tests, the feasibility and reliability of the proposed land-yacht modeling are verified. It can travel according to the given signal.

This land-yacht can be used in the Antarctic, outer planet or for harsh environment exploration.

A land-yacht is designed, and the contribution of this research is the development of a mathematical model for land-yacht robot. It provides a theoretical basis for analysis of the land-yacht’s motion.

In order to maintain the hinge moments of a combined pair of aircraft ailerons as low as possible each aileron is constructed so that when it is depressed to increase the camber of the wing its own camber is simultaneously increased. As shown, this is effected by making the aileron in two parts a, b hinged together at e, the leading portion a being adapted to be depressed whenever the aileron as a whole is depressed about the hinges c at the rear ends of brackets d. The dipping of the portion a is effected by a link t connected to a non‐rotatable nut r working on a threaded rod k, at the upper end of which is a pulley m actuated by a cable n that passes into the wing structure at a point in line with the axis c. A cable o which serves to vary the camber of the wing is associated with the cable n through a gearing‐up pulleys p, q.

This paper aims to design and control of a novel compact transportation system called the “wearable vehicle”. The wearable vehicle allows for traversing all types of terrains while transporting one's luggage in a comfortable and efficient manner.

The proposed design consists of a lower limb exoskeleton carrying two motorized wheels and two free wheels installed alongside its feet. This paper presents a detailed description of the system with its preliminary design and finite element analysis. Moreover, the system has been optimally designed to decrease wearable vehicle’s total weight, consequently leading to a reduction in motor size. Finally, two controllers have been designed to achieve stable operation of the wearable vehicle while walking. A PD controller with gravity compensation has been designed to ensure that the wearable vehicle tracks human motion, while a PID controller has been designed to ensure that the zero moment point is close to the center of the system’s support polygon.

Experimental tests were carried out to check the wearable vehicle concept. The obtained results prove the feasibility of the proposed wearable vehicle from the design, dynamics and control viewpoints.

This proposed wearable vehicle’s purpose is for traveling faster with less effort than normal walking. When a human comes across a flat open ground, the wearable vehicle can be used as a vehicle. However, when a human enters crowded traffic, an unstructured area or other obstacles like stairs, the vehicle can be switched into walking mode.

The wearable vehicle has seven DOFs exoskeletons, two motorized wheels, two free wheels and a foldable seat. It is used as a vehicle via its motorized and free wheels to travel fast with minimal effort. In addition, the human can switch easily into walking mode, if there is unstructured terrain to be traversed. Furthermore, an illustration of system's mechanisms and main feature parameters are presented to become acquainted with the ultimate benefits of the new system.

AMONG the many problems of drag reduction engaging the critical attention of aircraft designers to‐day, that parasitic appendix known as the undercarriage stands out, in more ways than one, as probably the most serious single offender still challenging the ingenuity of the designing engineer in his unceasing quest for aerodynamic refinement. Not so many years ago, however, quite a number of designers were openly sceptical of the mechanical feasibility of retracting the undercarriage unit; at least, in such a manner as to make it economically worth while. One suspects that our devotion in this country to the thin‐wing biplane had something to do with that particular brand of aerodynamic astigmatism, because it was not until the cantilever low‐wing monoplane became an accepted type that the idea of wheel retraction became a fashionable formula.

THE FUNDAMENTAL principles governing the behaviour of aircraft during steering manoeuvres on the ground are now well known and documented, but one particular aspect of the problem has not, to the writer's knowledge, been dealt with in the literature. This article examines this feature and describes methods for evaluating its effect on the overall steering power requirements and system behaviour. The influence of tyre characteristics is also examined.

THE second edition of the now classic Deutsch de la Meurthe Cup race showed considerable progress over the first competition; the principle of setting a relatively low limit for the cubic capacity of the engine and giving the designers an otherwise entirely free hand is unquestionably one of the best ways towards rapid technical strides. It must be particularly stressed that the competing machines had no certificate of airworthiness of any sort; in fact, Government control was for once completely left aside and the racers allowed to take part in the contest without having been subjected to the slightest examination of officials of the Ministère de l'Air. Thus manufacturers were relieved of the customary administrative difficulties and losses of time. The result proved perfectly satisfactory; machines were rapidly built and tried, they demonstrated remarkable flying qualities and performance, and technical advances of great practical value have been attained in a very short space of time. The experience is likely to have long‐reaching and beneficial results.

Dunlop Aviation Division has put into operation a new aircraft wheel roll machine at its Coventry site, a project which is valued at nearly £1 million.