Load-bearing swinging arm which causes an advance movement of a mobile device by means of its pivoting movement is pivotally connected to a supporting structure in a pivotal relationship thereto about an axis of rotation, and a pair of actuators for effecting the pivoting movement is provided between the swinging arm and the supporting structure. The points of action acting on the supporting structure by way of the actuators are provided on both sides of the axis of rotation. The points of action effect moment simultaneously about the axis of rotation, and they will also effect a force couple at least in some position, for example, in a position critical in view of the load, the forces acting through the points of action being parallel, of equal magnitude and having opposite senses in the force couple.
The invention relates to a device at a vehicle (8) supported and driven by articulated legs (10), the legs (10) comprising a number of leg-segments (1 . . . 7) which are moveably connected to the chassis (9) of the vehicle and to each other by means of joints (11 . . . 17). The two joints located closest to the vehicle are moveable relative to each other about axes, which are perpendicular to each other.
An actuator particularly for accomplishing the swinging motion of a swinging arm comprises two cylinders using a pressurized medium, the piston rods of the cylinders being connected to a structure rotatable in relation to the swinging arm for the purpose of rotating the swinging arm around a rotation axis by the effect of movements of the pistons of the cylinders. The actuator comprises two control valves, of which one control valve is arranged to guide the pressurized medium either to both cylinders while they are coupled in parallel, or solely to one cylinder where its piston rod chamber and piston chamber are coupled together. This results in a movement of the piston outwards, because the pressure is directed to the whole work area of the piston on the side of the piston chamber and on the side of the piston rod chamber only to the work area which is the difference between the cross-sectional areas of the piston and the piston rod. Further, the pressurized medium needs to be supplied only in an amount proportional to said difference for achieving the same speeds of motion as before.
A leg mechanism for moving a body comprising an upper arm pivotably connected to the body by a hip joint, and a lower arm pivotably connected to the opposite end of the upper arm by a knee joint. The lower end of the lower arm comprises a walk element for contacting a surface over which the body is moved. Between the upper arm and the body at the hip joint, and between the upper arm and the lower arm at the knee joint, respectively, there is an actuator for effecting the pivotal movement of the corresponding joint. At one of the joints there is, in addition to an active actuator, also a passive force-transmitting element arranged to transmit a change in a pivoting angle taking place at the joint under the effect of the active actuator and an external load. The passive force-transmitting element transforms the change into a force which is transmitted to a receiving actuator which effects a change in the position of the lower end of the lower arm to compensate for the change in the pivoting angle.
In one aspect, a supported walking system is disclosed, comprising a robotic walking figure and a wheeled support that at least partially supports the robotic walking figure. The supported walking system may be driven and controlled by a human operator. Computer algorithms automatically control the robot's walking functions so that it may step forwards, backwards, and sideways in synchronicity with the movements of the cart while driving and turning at varying speeds.
