Abstract: An input unit enters angular displacements by which drive shafts of a robot arm are to be turned as teaching data into a control unit. The control unit converts the input angular displacements into position-attitude data, namely, converted commands, indicating a position of the free end of the robot arm and an attitude of the robot in a rectangular coordinate system through forward conversion. The control unit corrects the position-attitude data on the basis of inherent errors in the robot to provide corrected position-attitude data. The control unit converts the corrected position-attitude data into corrected angular displacements through inverse conversion and gives the corrected angular displacements to an actuator included in the robot. The inherent errors in the robot include mechanismic errors resulting from machining errors and assembling errors, installation errors and errors in the origins of axes.

Abstract: A drive controller (10?) of the present invention comprises control means (28, 29, 32 to 38) configured to perform control to cause a driven element to move by a driver (M) and a collision detecting means (20?) configured to detect a collision of the driven element. The collision detecting means detects the collision of the driven element based on an estimated speed deviation which is an estimated deviation from an actual speed of the driven element or an estimated acceleration deviation which is an estimated deviation from an actual acceleration of the driven element.

Abstract: An input unit enters angular displacements by which drive shafts of a robot arm are to be turned as teaching data into a control unit. The control unit converts the input angular displacements into position-attitude data, namely, converted commands, indicating a position of the free end of the robot arm and an attitude of the robot in a rectangular coordinate system through forward conversion. The control unit corrects the position-attitude data on the basis of inherent errors in the robot to provide corrected position-attitude data. The control unit converts the corrected position-attitude data into corrected angular displacements through inverse conversion and gives the corrected angular displacements to an actuator included in the robot. The inherent errors in the robot include mechanismic errors resulting from machining errors and assembling errors, installation errors and errors in the origins of axes.

Abstract: A drive controller (10?) of the present invention comprises control means (28, 29, 32 to 38) configured to perform control to cause a driven element to move by a driver (M) and a collision detecting means (20) configured to detect a collision of the driven element. The collision detecting means detects the collision of the driven element based on an estimated speed deviation which is an estimated deviation from an actual speed of the driven element or an estimated acceleration deviation which is an estimated deviation from an actual acceleration of the driven element.

Abstract: Provided is a drive-controlling method and apparatus and a robot having the apparatus for precisely detecting a collision of a arm being driven by a robot with obstacles, and for keeping damages of the arm from the collision minimum: storing a route of the arm being driven by the robot in a memory; detecting a collision by comparing a current value of a servo motor which drives the arm and a reference current value; and controlling the robot such that the arm leaves a predetermined distance from the obstacle based on the stored route, backing up the arm along the same route as before the collision.

Abstract: A piezoelectric element characterized by comprising a piezoelectric crystal which has a crystal structure around the crystal phase boundary of tetragonal and rhombohedral (MPB) in a specific temperature range and at least most of which phase-transits to tetragonal when heated to a temperature range higher than the above specific temperature range, and a method for driving the piezoelectric element in a temperature range not lower than the above specific temperature range.

Abstract: The present invention relates to a piezoelectric ceramic composition for actuator which is a composition comprising a basic composition containing lead, lanthanum, alkali earth metals, zirconium, titanium and oxygen in the formulation represented by the following general formula (I): ##EQU1## where A represents one or more element(s) selected from the group consisting of Ba, Ca and Sr; 0<x.ltoreq.0.07; 0.40.ltoreq.y.ltoreq.0.65; and 0<m.ltoreq.0.15, wherein the ceramic composition containing, relative to the basic composition, one or more element(s) selected from the group consisting of iron, aluminum, manganese, indium and tellurium in an amount of 0.02 to 0.3% by weight in terms of Fe.sub.2 O.sub.3 or Al.sub.2 O.sub.3, 0.02 to 0.2% by weight in terms of MnO.sub.2 and 0.02 to 0.5% by weight in terms of In.sub.2 O.sub.3 or TeO.sub.2.

Abstract: A piezoelectric ceramic composition for actuators, composed of lead, lanthanum, zirconium, titanium, magnesium, zinc, niobium, manganese, chromium and oxygen atoms, which contains manganese in an amount of at most 1.5% by weight as calculated as Mn.sub.2 O and chromium in an amount of at most 0.5% by weight as calculated as Cr.sub.2 O.sub.3, relative to a main component composition of the formula (I):Pb.sub.(1-x) La.sub.x [(1-z)(Zr.sub.y Ti.sub.(1-y))+z{Mg.sub.q Zn.sub.(1-q)).sub.1/3 Nb.sub.2/3 }].sub.(1-x/4) O.sub.3 (I)wherein 0<x.ltoreq.0.07, 0.40.ltoreq.y.ltoreq.0.65, 0.ltoreq.q.ltoreq.1, and 0<z.ltoreq.0.40.

Abstract: The present invention relates to a piezoelectric ceramic composition for an actuator which is a ceramic composition comprising a main component represented by the formula: Pb.sub.(1-x) La.sub.x [Zr.sub.y Ti.sub.(1-y) ].sub.(1-x/4) O.sub.3 and, as a sub component, antinomy in an amount of more than 0.05% by weight and less than 3.0% by weight in terms of anitmony pentoxide relative to the main component. The piezoelectric ceramic composition of the present invention has a high electromechanical coupling factor, a high piezoelectric strain constant and a high Curie point, and is particularly excellent as a material for a piezoelectric actuator.

Abstract: A piezoelectric actuator comprising a longitudinal effect-type laminated piezoelectric element composed of piezoelectric ceramic sheets laminated in their thickness direction, and a supporting member fixed to one side in the longitudinal direction of the element and being bending and capable of constraining expansion of the element.

Abstract: A piezoelectric ceramic composition for actuators, which consists essentially of a composite of perovskite compounds represented by the formulaPb.sub.(1-x) La.sub.x [z{(Zn.sub..alpha. Mg.sub.(1-.alpha.))1/3Nb.sub.2/3 }+(1-z){Zr.sub.y Ti.sub.(1-y) }].sub.(1-x/4) O.sub.3wherein 0.03.ltoreq.x.ltoreq.0.07, 0.50.ltoreq.y.ltoreq.0.65, o<z<0.20, and 0<.alpha.<1.