Robot Stair Mapping With Movement Limits for Precise Foot Placement

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Robots face challenges in traversing environments with obstacles like stairs due to poor sensor data and the need for precise leg movement and foot placement, which can lead to missteps and potential damage.

Innovation Solution

A method for generating enhanced stair maps by merging sensor data with movement limitations to control robot navigation, including stair models and ground height maps, and implementing obstacle avoidance systems to ensure safe traversal.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If the robot uses sensor data to generate ground height maps and stair models for navigation, then the robot's ability to traverse complex terrains is improved, but the precision and reliability of stair detection and foot placement may deteriorate due to poor sensor data quality

Engineering Contradiction:
Improveability to traverse complex terrainsVSAvoidstair detection precision
Core Design Contradiction:
Adaptability or versatilityVSMeasurement precision

Solution Approach 1:

The patent merges multiple data sources including sensor data, pre-existing stair models, and movement limitations to create an enhanced stair map. This combination compensates for poor sensor data quality by integrating multiple information sources, thereby improving both adaptability to complex terrains and measurement precision of stair detection

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The enhanced stair map serves as an intermediary data structure that processes and reconciles information from sensor data, pre-existing models, and movement constraints. This intermediary layer filters and refines raw sensor data to improve detection precision while maintaining the ability to handle complex terrains

Inventive Principle:
Principle #24Intermediary (Mediator)

2Manufacturing precision

If the robot generates detailed enhanced stair maps with movement limitations, then foot placement accuracy is improved, but the computational complexity and processing time increase

Engineering Contradiction:
Improvefoot placement accuracyVSAvoidcomputational complexity
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The patent pre-computes movement limitations and integrates them into the enhanced stair map before real-time navigation. By performing these computational tasks in advance, the system reduces real-time processing requirements while maintaining high foot placement accuracy through pre-analyzed movement constraints

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The system applies different levels of computational detail to different regions of the environment. Enhanced stair maps with detailed movement limitations are generated only for stair regions where precise foot placement is critical, while other areas use simpler ground height maps, thereby reducing overall computational complexity while maintaining accuracy where needed

Inventive Principle:
Principle #3Local quality

3Reliability

If the robot constrains movements based on enhanced stair maps to prevent collisions, then safety is improved, but the robot's mobility and traversal speed are reduced

Engineering Contradiction:
ImprovesafetyVSAvoidtraversal speed
Core Design Contradiction:
ReliabilityVSSpeed

Solution Approach 1:

The robot dynamically adjusts movement constraints based on the enhanced stair map and real-time sensor data. Movement limitations are applied adaptively - strictly enforced in hazardous regions identified by the enhanced stair map, and relaxed in safe regions - thereby maintaining safety while preserving traversal speed where constraints are not needed

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The navigation space is segmented into different regions with different constraint levels based on the enhanced stair map. Critical stair edges and hazardous areas are identified and segmented as no-step zones, while safe areas allow more flexible movement. This segmentation enables the robot to maintain safety in critical zones while moving efficiently in safe zones

Inventive Principle:
Principle #1Segmentation

Data Source

PatentEP4418066B1Stair tracking for modeled and perceived terrain
Publication Date: 2026.01.28 BOSTON DYNAMICS INC
  • EP4418066B1 patent drawingFigure 1A
  • EP4418066B1 patent drawingFigure 1B
  • EP4418066B1 patent drawingFigure 2A

AI summary

A method of stair tracking for modeled and perceived terrain includes receiving sensor data (134) about an environment (10) of a robot (100). The method also includes generating a set of maps (182) based on voxels corresponding to the received sensor data. The set of maps includes a ground height map and a map of movement limitations for the robot. The map of movement limitations identifies illegal regions within the environment that the robot should avoid entering. The method further includes generating a stair model (202) for a set of stairs (20) within the environment based on the sensor data, merging the stair model and the map of movement limitations to generate an enhanced stair map, and controlling the robot based on the enhanced stair map or the ground height map to traverse the environment.