Showing papers on "Angular displacement published in 1967"

Inductive angular position transmitter

Abstract: 1,122,763. Angular displacement transducers. MERCKLE FLUGZEUGWERKE G.m.b.H. March 14, 1967, No. 11828/67. Heading G1N. [Also in Division H1] An inductive transducer for measuring angular displacement comprises two rectangular coils 1, 2 (Fig. 2A) assembled with their planes at right angles, surrounded by a tube 3 of non-magnetic, electrically conductive material, e.g. aluminium, with a longitudinal slot 4. Coil 1 is energized with A. C., and the distortion of the resulting magnetic field produced by the assymetric eddy currents in tube 3 causes an induced voltage to appear in coil 2, whose amplitude is indicative of the angular relationship between the tube and the coil assembly.

Rotary transformer nulling system

Abstract: AN APPARATUS INCLUDING A FOLLOW-UP HAVING NO MOVING PARTS FOR PROVIDING AN OUTPUT CORRESPONDING TO THE ANGULAR DISPLACEMENT OF THE ROTOR OF A ROTARY TRANSFORMER, SUCH AS A SYNCHRO OR RESOLVER, COMPRISING A LOGIC NETWORK CONNECTED TO THE ROTOR OF THE ROTARY TRANSFORMER AND RECEIVING ERROR SIGNALS THEREFROM AND PROVIDING AN OUTPUT CORRESPONDING TO THE ANGULAR DISPLACEMENT OF THE ROTOR FROM A PREDETERMINED POSITION, AND THE OUTPUT OF THE LOGIC NETWORK BEING APPLIED TO THE STATOR WINDINGS OF THE ROTARY TRANSFORMER AND ROTATING THE STATOR MAGNETIC FIELD TO NULL THE ERROR SIGNALS FROM THE ROTOR. THE LOGIC NETWORK MAY PROVIDE EITHER AN ANALOG OR DIGITAL OUTPUT CORRESPONDING TO THE ANGULAR DISPLACEMENT OF THE ROTOR.

On the Use of Electrically Stimulated Muscle as a Controlled Actuator of a Limb

Abstract: : The feasibility of inducing controlled movement of a paralyzed limb by means of applying electric currents is discussed. This is preceded by a functional description of muscle and its electrical excitability and the musculo-skeletal system of the human arm. Experiments are described which were performed to gain a basic understanding of the mechanical response of the lower arm due to stimulation of the biceps muscle. The dynamic model of this single degree of freedom system thus obtained is then used to synthesize suitable feedback control schemes. Two basically different systems are discussed: the control of the angular position, and the control of the angular velocity of the elbow joint. The velocity controller is found to be superior-and is implemented in hardware. Three types of velocity controllers are compared: open loop, proportional closed loop, and proportional plus integral closed-loop. The proportional plus integral closed loop is found to be superior. The author also indicates that a closed loop torque control may perform as well or better and also is simpler to implement.

Method for generating ultra-precise angles

Abstract: A METHOD FOR GENERATING ULTRA-PRECISE ANGLES EMPLOYING A ROTATABLY SUPPORTED TRIANGULAR PRISM AND A FIXED POSITION LIGHT REFLECTING MIRROR ADAPTED, WHEN THE PRISM IS IN A REFERENCE POSITION, TO REFLECT AS A PARALLEL RETURN RAY A GIVEN RAY OF MONOCHROMATIC LIGHT INCIDENT UPON THE PRISM. UPON ROTATION OF THE PRISM THROUGH A MONITORED ANGULAR DISPLACEMENT ABOUT AN AXIS PARALLEL TO THE PRISM REFRACTING SURFACES, THERE IS GENERATED AN ANGLE DEFINED BY THE RESULTANT ANGULAR DISPLACEMENT OF THE REFLECTED RETURN RAY WITH RESPECT TO THE INCIDENT RAY, THE ANGLE THUS GENERATED BEING SUBSTANTIALLY SMALLER THAN THE MONITORED ANGULAR DISPLACEMENT OF THE PRISM, WHEREBY SIGNIFICANTLY REDUCING ANY ERROR INTRODUCED IN DETERMINING THE VALUE OF THE GENERATED ANGLE DUE TO ERROR ENCOUNTERED IN MONITORING UTILITY IN TESTING AND CALIBRATING OF BODY ROTATION MONITORING DEVICES, SUCH AS AUTOCOLLIMATORS.

Motion of a rigid body

Abstract: This chapter discusses some types of motion of a rigid body. In mechanics, rigid body means that the relative position of the parts of a body remains unchanged during the motion. The body, thus, moves as a whole. The simplest motion of a rigid body is one in which it moves parallel to itself; this is called translation. For example, if a compass is moved smoothly in a horizontal plane, the needle will retain a steady north-south direction and will execute a translational motion. In translational motion of a rigid body, every point in it has the same velocity and describes a path of the same shape, there being merely a displacement between the paths. Another simple type of motion of a rigid body is rotation about an axis. The chapter describes the energy of a rigid body in motion, rotational angular momentum, gyroscope, and inertia forces.

Positioning device for end loop forming means for spring coiling machine

Abstract: 1,070,544. Coiling. ASSOCIATED SPRING CORPORATION. Oct. 6, 1964, No. 40638/64. Heading B3E. A machine for forming a helical tension spring having loops at both ends comprises means at a first station for forming wire 6 into a helix with an end loop extending outwardly from the first end, means for cutting the helix from the wire, a transfer mechanism 10 for grasping the cut-off helix and moving it to a second station where an end loop is formed on the second end by tools 20, 22, and means 30, 32 on the transfer mechanism for engaging the sides of the first end loop and rotating the helix about its axis to a predetermined position whereby the loop formed on the second end will have a predetermined angular relationship to that on the first end. The wire 6 is fed by rolls 2, 4 against a coiling point (not shown) to form the helix and the first end loop. The transfer mechanism comprises a block 10 movable about a pivot 12 by a piston-rod 14. Jaws 16, 18 are mounted on the block and actuated by fluid pressure to grip the helix. Positioning means 30, 32 are carried by the jaws and have surfaces 44, Fig. 2 (not shown), to engage the first end loop and locate it during transfer to the tools 20, 22 which form the second end loop. The surfaces 44 may be arranged horizontally, Fig. 4 (not shown), or in any other angular position.

Rotational Displacement Transducer

Abstract: The construction and calibration of a rotational displacement transducer, using light sensitive resistors and a variable slit, are described. The instrument is capable of measuring both static and dynamic angular displacements and has a continuous range of sensitivity with a resolution as low as 0.01°. The linearity of the response over a 50° linear region is within 1% of the full scale deflection of 135°. The transducer exhibits no substantial phase lag and has response well suited for low frequency oscillation studies in the range 0–50 cps. The device is light in weight and has free undamped motion due to an external air‐bearing suspension system. A restriction which must be noted in applying the transducer is that because of high frequency response dropoff the instrument is suitable only for recording accurately low frequency angular displacements of quasiharmonic waveform.