US 2015/0088469 A1 · Automatic Task-Specific Model Reduction for Humanoid Robots

Abstract

The disclosure provides an approach for automatically determining task-specific robot model reductions. In one embodiment, a simplification application determines a smallest order statespace model whose stabilizing controller also stabilizes a full-order robot model. The simplification application may determine such a model via an iterative procedure in which the reduced order is initialized to the number of unstable poles of the open-loop full-order system and, while the closed loop full-order system with the balanced reduced order system's stabilizing controller is unstable, fractional balanced reduction is applied to generate a balanced reduced system. If one or more unstable closed-loop poles exist in the full-order system with the stabilizing controller of the newly-generated balanced reduced system, the reduced order is incremented by one, and fractional balanced reduction repeated, until no unstable closed-loop poles remain. In another embodiment, the model reduction is made task-specific by formulating the full model with task-specific outputs.

Claims20

Dependent claims

A computer-implemented method for simplifying a model of a robot, comprising:

receiving the robot model and a controller, wherein the received robot model includes one or more equations with mass and dynamic properties of the robot used to simulate motion of the robot, and wherein the controller is configured to compute inputs to the received robot model for achieving one or more control objectives;
receiving task-specific output corresponding to a task or motion to be performed;
and
performing, via one or more processors, a search on an order of the received robot model to obtain a minimum stable reduced order robot model and a first stabilizing controller associated therewith given the received robot model, the controller, and the received task-specific output,
wherein the first stabilizing controller also stabilizes the received robot model.

2 more elements

A non-transitory computer-readable storage media storing instructions, which when executed by a computer system, perform operations for simplifying a model of a robot, the operations comprising:

receiving the robot model and a controller, wherein the received robot model includes one or more equations with mass and dynamic properties of the robot used to simulate motion of the robot, and wherein the controller is configured to compute inputs to the received robot model for achieving one or more control objectives;
receiving task-specific output corresponding to a task or motion to be performed;
and
performing a search on an order of the received robot model to obtain a minimum stable reduced order robot model and a first stabilizing controller associated therewith given the received robot model, the controller, and the received task-specific output,
wherein the first stabilizing controller also stabilizes the received robot model.

2 more elements

A system, comprising:

a processor;
and
a memory, wherein the memory includes an application program configured to perform operations for simplifying a model of a robot, the operations comprising:
receiving the robot model and a controller, wherein the received robot model includes one or more equations with mass and dynamic properties of the robot used to simulate motion of the robot, and wherein the controller is configured to compute inputs to the received robot model for achieving one or more control objectives,
receiving task-specific output corresponding to a task or motion to be performed, and
performing a search on an order of the received robot model to obtain a minimum stable reduced order robot model and a first stabilizing controller associated therewith given the received robot model, the controller, and the received task-specific output;
wherein the first stabilizing controller also stabilizes the received robot model.

4 more elements

Dependencies are inferred from the claim text.

Automatic Task-Specific Model Reduction for Humanoid Robots

Life of this patent

Automatic Task-Specific Model Reduction for Humanoid Robots

Life of this patent

Abstract

Claims20