RobotLocomotion/drake
Nov 2024 – Jul 2026
18 Months active
Languages Used
C++MarkdownPythonBazel
Technical Skills
C++ DevelopmentMultibody DynamicsRoboticsSoftware EngineeringC++Linear Algebra
Michael Sherman
PROFILE
Michael Sherman
Over 18 months, contributed to RobotLocomotion/drake by engineering core features and optimizations in multibody dynamics, simulation fidelity, and API design. Developed and refactored C++ code to enhance joint modeling, frame handling, and performance, introducing new abstractions like SpanningForest and JointOrdinal for safer, clearer APIs. Improved simulation speed and accuracy through targeted optimizations, robust testing, and benchmarking, while maintaining backward compatibility via careful deprecation management. Addressed reliability in welding systems, gravity computations, and symbolic dynamics, and standardized terminology for maintainability. Work emphasized code clarity, maintainability, and extensibility, leveraging C++, Python, and Bazel to support advanced robotics and simulation workflows.
Overall Statistics
Feature vs Bugs
82%Features
Repository Contributions
37Total
Bugs
5
Commits
37
Features
23
Lines of code
22,990
Activity Months18
Your Network
39 peopleShared Repositories
39
Work History
July 2026
1 Commits • 1 Features
Jul 1, 2026July 2026: Delivered a non-functional but high-impact terminology standardization in Drake's multibody module to unify welded-links terminology under 'fuse'/'fused', improving API clarity and future maintainability. Implemented via commit 268c99473000033144ca9a79fa7b11758ced9dac with updates to topology and MbP-related paths; tests and docs updated to reflect the change. No user-facing bugs fixed this month; activity focused on refactor, doc/test alignment, and base for upcoming features.
1 Commits • 1 Features
Jul 1, 2026July 2026: Delivered a non-functional but high-impact terminology standardization in Drake's multibody module to unify welded-links terminology under 'fuse'/'fused', improving API clarity and future maintainability. Implemented via commit 268c99473000033144ca9a79fa7b11758ced9dac with updates to topology and MbP-related paths; tests and docs updated to reflect the change. No user-facing bugs fixed this month; activity focused on refactor, doc/test alignment, and base for upcoming features.
July 2026
June 2026
2 Commits • 1 Features
Jun 1, 2026Month: 2026-06. In RobotLocomotion/drake, delivered gravity computation performance and accuracy improvements for multibody simulations. Implemented a fast Jacobian-transpose-times-vector operator for gravity torques and refactored gravity calculations to improve accuracy and efficiency, with new methods for calculating gravitational forces and potential energy. These changes streamline physics calculations and enable faster, more reliable simulations and planning iterations.
June 2026
2 Commits • 1 Features
Jun 1, 2026Month: 2026-06. In RobotLocomotion/drake, delivered gravity computation performance and accuracy improvements for multibody simulations. Implemented a fast Jacobian-transpose-times-vector operator for gravity torques and refactored gravity calculations to improve accuracy and efficiency, with new methods for calculating gravitational forces and potential energy. These changes streamline physics calculations and enable faster, more reliable simulations and planning iterations.
May 2026
2 Commits • 2 Features
May 1, 2026Month: 2026-05 — Key features delivered and major accomplishments: 1) Composite body support in the multibody system: groundwork with renaming/refactoring to accommodate composite structures; enhances handling of links and joints for future composite features. Commit: 76a9173f9c60718b21d69b039bdd667dcf9d5556. 2) Performance benchmarks for CalcGravityGeneralizedForces: added performance tests to strengthen the testing framework for the Cassie model and assess efficiency under varying conditions. Commit: 3ec067a3ee128487c49acbfadf13e2f9870241aa. Major bugs fixed: none reported this month; minor maintenance included misc comment cleanups. Overall impact: establishes foundational support for composite bodies and expands robust performance testing, enabling safer refactors and better performance assurance. Technologies/skills demonstrated: C++/Drake codebase refactoring, naming/infrastructure changes, multibody modeling, performance benchmarking, and test framework enhancements.
2 Commits • 2 Features
May 1, 2026Month: 2026-05 — Key features delivered and major accomplishments: 1) Composite body support in the multibody system: groundwork with renaming/refactoring to accommodate composite structures; enhances handling of links and joints for future composite features. Commit: 76a9173f9c60718b21d69b039bdd667dcf9d5556. 2) Performance benchmarks for CalcGravityGeneralizedForces: added performance tests to strengthen the testing framework for the Cassie model and assess efficiency under varying conditions. Commit: 3ec067a3ee128487c49acbfadf13e2f9870241aa. Major bugs fixed: none reported this month; minor maintenance included misc comment cleanups. Overall impact: establishes foundational support for composite bodies and expands robust performance testing, enabling safer refactors and better performance assurance. Technologies/skills demonstrated: C++/Drake codebase refactoring, naming/infrastructure changes, multibody modeling, performance benchmarking, and test framework enhancements.
May 2026
March 2026
1 Commits • 1 Features
Mar 1, 2026March 2026 monthly summary for RobotLocomotion/drake focused on delivering a feature that enhances multi-body dynamics fidelity and reliability in the ICF solver.
March 2026
1 Commits • 1 Features
Mar 1, 2026March 2026 monthly summary for RobotLocomotion/drake focused on delivering a feature that enhances multi-body dynamics fidelity and reliability in the ICF solver.
December 2025
1 Commits • 1 Features
Dec 1, 2025December 2025: Focused on API deprecation strategy and backward compatibility in Drake. Implemented a grace period extension for deprecated Floating Base API methods, ensuring a smoother transition for users and preserving stability for downstream systems while maintaining clear upgrade paths.
1 Commits • 1 Features
Dec 1, 2025December 2025: Focused on API deprecation strategy and backward compatibility in Drake. Implemented a grace period extension for deprecated Floating Base API methods, ensuring a smoother transition for users and preserving stability for downstream systems while maintaining clear upgrade paths.
December 2025
November 2025
1 Commits • 1 Features
Nov 1, 2025Concise monthly summary for 2025-11 focusing on key accomplishments, major fixes, and overall impact for RobotLocomotion/drake activity.
November 2025
1 Commits • 1 Features
Nov 1, 2025Concise monthly summary for 2025-11 focusing on key accomplishments, major fixes, and overall impact for RobotLocomotion/drake activity.
October 2025
2 Commits • 2 Features
Oct 1, 2025October 2025 monthly summary for RobotLocomotion/drake: Architectural modernization of multibody topology, ongoing API alignment, and tutorial resilience to API changes. Focused on reducing technical debt, improving maintainability, and safeguarding downstream usage.
2 Commits • 2 Features
Oct 1, 2025October 2025 monthly summary for RobotLocomotion/drake: Architectural modernization of multibody topology, ongoing API alignment, and tutorial resilience to API changes. Focused on reducing technical debt, improving maintainability, and safeguarding downstream usage.
October 2025
September 2025
2 Commits • 1 Features
Sep 1, 2025Month: 2025-09. Focused on robustness and API clarity for multi-instance modeling in Drake. Key work delivered includes a floating base bodies API refactor and a bug fix for model instance coordinate tracking. Impact includes improved accuracy, safer API evolution, and clearer semantics for kinematic/dynamic computations in MultibodyPlant/MultibodyTree. Technologies demonstrated include C++ API design, deprecation strategies, and rigorous regression tracing via commits.
September 2025
2 Commits • 1 Features
Sep 1, 2025Month: 2025-09. Focused on robustness and API clarity for multi-instance modeling in Drake. Key work delivered includes a floating base bodies API refactor and a bug fix for model instance coordinate tracking. Impact includes improved accuracy, safer API evolution, and clearer semantics for kinematic/dynamic computations in MultibodyPlant/MultibodyTree. Technologies demonstrated include C++ API design, deprecation strategies, and rigorous regression tracing via commits.
August 2025
1 Commits • 1 Features
Aug 1, 2025August 2025 Drake work focused on refactoring the kinematic tree to use SpanningForest, reducing dependency on MultibodyTopology and simplifying internal data structures. No major bug fixes in this scope. This work improves maintainability and sets the stage for future performance enhancements and feature development.
1 Commits • 1 Features
Aug 1, 2025August 2025 Drake work focused on refactoring the kinematic tree to use SpanningForest, reducing dependency on MultibodyTopology and simplifying internal data structures. No major bug fixes in this scope. This work improves maintainability and sets the stage for future performance enhancements and feature development.
August 2025
July 2025
1 Commits • 1 Features
Jul 1, 2025July 2025 performance summary for RobotLocomotion/drake: Implemented a safer joint-ordinal API by introducing a dedicated JointOrdinal type to represent joint ordinals in the multibody plant system, replacing raw integers. This change reduces misuse, improves type safety and code clarity; APIs and tests were updated to adopt JointOrdinal. Commit 56b1c5fce3596340cab1d5dfc9f007a119964f88 (PR #23214) accompanies this work. This foundation enables safer future refactors and reduces long-term maintenance risk.
July 2025
1 Commits • 1 Features
Jul 1, 2025July 2025 performance summary for RobotLocomotion/drake: Implemented a safer joint-ordinal API by introducing a dedicated JointOrdinal type to represent joint ordinals in the multibody plant system, replacing raw integers. This change reduces misuse, improves type safety and code clarity; APIs and tests were updated to adopt JointOrdinal. Commit 56b1c5fce3596340cab1d5dfc9f007a119964f88 (PR #23214) accompanies this work. This foundation enables safer future refactors and reduces long-term maintenance risk.
June 2025
2 Commits • 1 Features
Jun 1, 2025June 2025 monthly summary for RobotLocomotion/drake focused on performance optimizations in the multibody dynamics core, with refactoring, caching, and benchmarking to prepare for M-frame integration. Deliverables include a faster BlockSystemJacobian, clarified mass matrix computations, and Cassie-based benchmarking to quantify improvements. No major bug fixes documented this month; effort prioritized performance, reliability, and groundwork for future features.
2 Commits • 1 Features
Jun 1, 2025June 2025 monthly summary for RobotLocomotion/drake focused on performance optimizations in the multibody dynamics core, with refactoring, caching, and benchmarking to prepare for M-frame integration. Deliverables include a faster BlockSystemJacobian, clarified mass matrix computations, and Cassie-based benchmarking to quantify improvements. No major bug fixes documented this month; effort prioritized performance, reliability, and groundwork for future features.
June 2025
May 2025
3 Commits • 1 Features
May 1, 2025May 2025 monthly summary for RobotLocomotion/drake focusing on reliability, performance, and correctness improvements in multibody dynamics. Key deliveries included robustness fixes for the welding system, performance optimizations for dynamics calculations, and correctness enhancements for symbolic dynamics. Overall impact reflects improved robustness in simulation scenarios, faster kinematics, and more reliable mass matrix computations.
May 2025
3 Commits • 1 Features
May 1, 2025May 2025 monthly summary for RobotLocomotion/drake focusing on reliability, performance, and correctness improvements in multibody dynamics. Key deliveries included robustness fixes for the welding system, performance optimizations for dynamics calculations, and correctness enhancements for symbolic dynamics. Overall impact reflects improved robustness in simulation scenarios, faster kinematics, and more reliable mass matrix computations.
April 2025
6 Commits • 3 Features
Apr 1, 2025In April 2025, focused on optimizing Drake's multibody dynamics and expanding joint configuration support. Delivered performance improvements for axial rotations and mobilizers, enabled reversed joints with enhanced loop detection, and strengthened tests for mobilizer transforms, resulting in faster, more robust simulations and broader configuration support.
6 Commits • 3 Features
Apr 1, 2025In April 2025, focused on optimizing Drake's multibody dynamics and expanding joint configuration support. Delivered performance improvements for axial rotations and mobilizers, enabled reversed joints with enhanced loop detection, and strengthened tests for mobilizer transforms, resulting in faster, more robust simulations and broader configuration support.
April 2025
March 2025
4 Commits • 2 Features
Mar 1, 2025March 2025 focused on strengthening Drake's core simulation infrastructure: robust frame cloning, clearer ephemeral element handling, and enhanced control over integrator startup state. The work delivers reliable model behavior, reproducible simulations, and improved developer ergonomics—supporting more predictable experimentation and faster debugging.
March 2025
4 Commits • 2 Features
Mar 1, 2025March 2025 focused on strengthening Drake's core simulation infrastructure: robust frame cloning, clearer ephemeral element handling, and enhanced control over integrator startup state. The work delivers reliable model behavior, reproducible simulations, and improved developer ergonomics—supporting more predictable experimentation and faster debugging.
February 2025
3 Commits • 1 Features
Feb 1, 2025February 2025 monthly summary for RobotLocomotion/drake focused on simplifying and hardening the joint/mobilizer plumbing and expanding frame handling to improve modeling flexibility and consistency. The month delivered structural refactors that remove legacy abstractions and enable frame-aware mobilizers, laying groundwork for more robust simulations and easier future maintenance. Key outcomes: - Simplified joint mobilizer creation by removing the BluePrint abstraction and directly associating Mobilizers with Joints, reducing technical debt and fragility. - Eliminated JointImplementation and JointImplementationBuilder, streamlining the internal pipeline and improving clarity of the mobilizer-to-joint flow. - Enhanced frame support by enabling MakeMobilizerForJoint() to create Frames, with explicit support for offset weld frames, increasing modeling versatility across joints. Impact: - Improves modeling flexibility, consistency, and maintainability across the Drake joint/mobilizer subsystem. - Establishes a cleaner foundation for future features and more reliable simulations. Technologies/skills demonstrated: - C++/ Drake core refactoring, frame handling, and mobilizer integration. - Legacy abstraction removal and codebase modernization with attention to backward compatibility and testability.
3 Commits • 1 Features
Feb 1, 2025February 2025 monthly summary for RobotLocomotion/drake focused on simplifying and hardening the joint/mobilizer plumbing and expanding frame handling to improve modeling flexibility and consistency. The month delivered structural refactors that remove legacy abstractions and enable frame-aware mobilizers, laying groundwork for more robust simulations and easier future maintenance. Key outcomes: - Simplified joint mobilizer creation by removing the BluePrint abstraction and directly associating Mobilizers with Joints, reducing technical debt and fragility. - Eliminated JointImplementation and JointImplementationBuilder, streamlining the internal pipeline and improving clarity of the mobilizer-to-joint flow. - Enhanced frame support by enabling MakeMobilizerForJoint() to create Frames, with explicit support for offset weld frames, increasing modeling versatility across joints. Impact: - Improves modeling flexibility, consistency, and maintainability across the Drake joint/mobilizer subsystem. - Establishes a cleaner foundation for future features and more reliable simulations. Technologies/skills demonstrated: - C++/ Drake core refactoring, frame handling, and mobilizer integration. - Legacy abstraction removal and codebase modernization with attention to backward compatibility and testability.
February 2025
January 2025
2 Commits • 1 Features
Jan 1, 2025January 2025 — Drake: Delivered key feature and tooling improvements that enhance kinematic accuracy and developer tooling. Highlights include M-frame curvilinear mobilizer enhancements with velocity and acceleration computations and an updated trajectory class for M-frame compatibility; plus a CLion formatting tooling fix to ensure clang-format applies to the intended files. Commits: d1f9bfc2b90f798001f78ab1d3f7530bbaf3ae1c, 3a0b5ad37ea3a9dd2a7605143937031490fa36ae. Business value: improved simulation accuracy and consistency in movement modeling; reduced formatting drift and setup time for CLion users; overall code quality and maintainability improved through traceable changes. Technologies/skills demonstrated: C++, Drake framework, M-frame math, trajectory modeling, and CLion tooling/formatting automation.
January 2025
2 Commits • 1 Features
Jan 1, 2025January 2025 — Drake: Delivered key feature and tooling improvements that enhance kinematic accuracy and developer tooling. Highlights include M-frame curvilinear mobilizer enhancements with velocity and acceleration computations and an updated trajectory class for M-frame compatibility; plus a CLion formatting tooling fix to ensure clang-format applies to the intended files. Commits: d1f9bfc2b90f798001f78ab1d3f7530bbaf3ae1c, 3a0b5ad37ea3a9dd2a7605143937031490fa36ae. Business value: improved simulation accuracy and consistency in movement modeling; reduced formatting drift and setup time for CLion users; overall code quality and maintainability improved through traceable changes. Technologies/skills demonstrated: C++, Drake framework, M-frame math, trajectory modeling, and CLion tooling/formatting automation.
December 2024
1 Commits • 1 Features
Dec 1, 2024December 2024 monthly summary for RobotLocomotion/drake. Focused on performance and numerical accuracy improvements in inertia workflows. Key deliverable: Inertia computation optimization and SpatialInertia refactor. Implemented manual inertia-vector multiplication to avoid potential slowdowns from Eigen's symmetric matrix multiplication. Refactored SpatialInertia to use pre-calculated mass and center-of-mass moment. Updated kinetic energy test tolerance to improve numerical accuracy. This work is captured in commit 4ee5832b42973c9643b4f677543bc813891d125c (Some speedups for inertia * vector (#22287)).
1 Commits • 1 Features
Dec 1, 2024December 2024 monthly summary for RobotLocomotion/drake. Focused on performance and numerical accuracy improvements in inertia workflows. Key deliverable: Inertia computation optimization and SpatialInertia refactor. Implemented manual inertia-vector multiplication to avoid potential slowdowns from Eigen's symmetric matrix multiplication. Refactored SpatialInertia to use pre-calculated mass and center-of-mass moment. Updated kinetic energy test tolerance to improve numerical accuracy. This work is captured in commit 4ee5832b42973c9643b4f677543bc813891d125c (Some speedups for inertia * vector (#22287)).
December 2024
November 2024
2 Commits • 1 Features
Nov 1, 2024November 2024 Drake development focused on expanding MultibodyPlant joint modeling and improving simulation fidelity. Implemented RpyFloating joint support for floating bodies and added reversed Weld joint capability, broadening base-body parameterization and degrees of freedom. Verified correctness through updated reaction force calculations and tests across configurations, establishing groundwork for more flexible robotics simulations and higher-fidelity models. No major bugs reported; this work enhances modeling flexibility, reliability, and future extensibility.
November 2024
2 Commits • 1 Features
Nov 1, 2024November 2024 Drake development focused on expanding MultibodyPlant joint modeling and improving simulation fidelity. Implemented RpyFloating joint support for floating bodies and added reversed Weld joint capability, broadening base-body parameterization and degrees of freedom. Verified correctness through updated reaction force calculations and tests across configurations, establishing groundwork for more flexible robotics simulations and higher-fidelity models. No major bugs reported; this work enhances modeling flexibility, reliability, and future extensibility.
Activity
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Quality Metrics
Correctness97.0%
Maintainability93.4%
Architecture94.8%
Performance90.6%
AI Usage23.8%
Skills & Technologies
Programming Languages
BazelC++MarkdownPython
Technical Skills
API DesignAPI DevelopmentAPI UpdatesBazelBenchmarkingC++C++ DevelopmentC++ developmentC++ programmingCode RefactoringDeprecation ManagementDocumentationGeometryKinematicsLinear Algebra
Repositories Contributed To
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