Abstract: An improved method and apparatus for computing the speed of a robot. Specifically, the method and apparatus relate to calculating the speed of a robot based on the rated maximum speed of a joint of the robot and one of the current position and joint information. There are further aspects of the invention to calculate the speed of a scalar robot, a scalar robot with two degrees of freedom within a horizontal plane, a scalar robot with two degrees of freedom within a horizontal plane plus a front end shaft, a cylindrical robot having two degrees of freedom within a horizontal plane, and other configurations.

Abstract: In a trajectory control method for an intra-planar multifreedom SCARA type of robot, a positional increment for an arm tip is computed for a linear interpolating operation through the expression described below. Namely, the expression is Vn=L.sub.1 .multidot.sin(.theta..sub.2).multidot.J.sub.1, wherein Vn indicates a positional increment of an arm tip; L.sub.1 indicates a length of a first arm; .theta..sub.2 indicates an angle of a second joint; and J.sub.1 indicates an angular velocity of a first joint (instructed angular velocity) specified by a user.

Abstract: A programmable controller 1, capable of programming the whole operations of the factory cell 3 including a robot, is provided with a program input device 11 and comprises: a memory for storing the program, a discrimination means 13 for discriminating the blocks within the program which define the movements of the robot; an information generation circuit 14 for generating information relative to the movement of the robot, which is transmitted to the robot controller 2 via a communication means 16a; and an instruction processing circuit 15 which executes via the contact input and output circuits 17 and 18 the instructions other than those of the robot defining blocks, relative to the states of contacts and relays of the factory cell 3, in parallel with the movements of the robot controlled by the robot controller 2.