Automatic trajectory generation for controlling a drive system
AssigneeFesto AG & Co.
InventorsColin Leitner, Ralph Unden, Ognjen Drazic
Life of this patent
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Abstract
A method and a trajectory generator are provided which automatically generate a trajectory, which is converted into control signals (sd) for the purpose of controlling a drive system. The control signals (sd) are used to control actuators of the drive system to carry out the movement according to the calculated trajectory. The method is implemented on a microcontroller (μC) and has a very short runtime and a low memory requirement.
Claims18
A computer-aided method for calculating trajectories for controlling end effectors of a drive system from a starting state into an end state on a predefined path, the method comprising:
- —capturing a starting state and an end state;
- —reading in limit values for an acceleration, a jerk, and a velocity, respectively;
- —calculating with a calculation method a trajectory from the captured starting state into the captured end state to minimize a trajectory time, wherein the calculation method includes:
- —checking whether a read-in limit value for the velocity has a permissible solution in a positive or negative direction to get from the starting state to the end when the read-in limit value for the velocity has the permissible solution in the positive or negative direction to get from the starting state to the end state, defining the read-in limit value as a center velocity;
- and when the read-in limit value for the velocity does not have the permissible solution in the positive or negative direction to get from the starting state to the end state:
- —carrying out a first calculating method for calculating a lower limit of a search interval;
- —carrying out a second calculating method for calculating an upper limit of the search interval;
- and —determining the center velocity in the search interval with an iterative optimization method,
- controlling the drive system for carrying out a movement,
- and wherein the iterative optimization method carries out optimization according to the velocity by iteratively shifting at least one of the upper or the lower search limit to restrict the search interval.
A trajectory generator for automatically calculating a trajectory for a drive system from a starting state into an end state on a predefined path, the trajectory generator comprising:
- an input interface configured to capture a starting state and an end state and to read in limit values for an acceleration, a jerk, and a velocity, respectively;
- and
- an arithmetic unit configured to carry out a calculation method for calculating a trajectory from the captured starting state into the captured end state to minimize a trajectory time;
- wherein the arithmetic unit includes:
- a checking unit configured to check whether the limit value read in for the velocity has a permissible solution in a positive or a negative direction to get from the starting state to the end state, and if so, defines this limit value which has been read in as the center velocity;
- and
- an optimizer configured to carry out a first calculating method for calculating a lower limit of a search interval, a second calculating method for calculating an upper limit of the search interval, and an iterative optimization method for determining the center velocity in the search interval, wherein the iterative optimization method carries out optimization according to the velocity by iteratively shifting at least one of the upper or the lower search limit to restrict the search interval.
Dependencies are inferred from the claim text.