Software Engineer - Humanoid Sim-to-Real

Apptronik; Austin (TX); On-site; USD 120,000 - 180,000; Full time

Job summary

Apptronik is building real-world humanoid robots. This role focuses on actuating models and control loops to bridge simulation and hardware, ensuring high fidelity from bench to deployment.

You will develop actuator models, perform system identification, and work with Controls, Firmware, and Simulation teams to align model fidelity with real-world performance.

Qualifications

• BS in Robotics, ME, EE, CS, or related field with 4 years of experience.
• MS in related field with 2 years of experience.
• PhD in related field.
• Prior humanoid or legged-robot experience is strongly preferred.

Responsibilities

• Develop and maintain high-fidelity actuator models in simulation that reflect friction, compliance, thermal, torque and current limits.
• Design, tune, and deploy actuator-level control—closed-loop torque and current control on hardware.

Skills

C++

Python

Actuator control

System identification

Motor electromechanics

Lab instrumentation

Education

BS in Robotics/ME/EE/CS

MS in related field

PhD in related field

Tools

MuJoCo

Isaac Sim

Brax

Docker

GPU/cloud infra

Job description

Software Engineer - Humanoid Sim-to-Real

Austin, TX

Apptronik is a human-centered robotics company developing AI-powered robots to support humanity in every facet of life. Our flagship humanoid robot, Apollo, is built to collaborate thoughtfully with people, starting with critical industries such as manufacturing and logistics, with future applications in healthcare, the home, and beyond.

We operate at the cutting edge of Applied AI, applying our expertise across the full robotics stack to solve some of society's most important problems. You will join a team dedicated to bringing Apollo to market at scale, tackling the complex challenges like safety, commercialization, and mass production to change the world for the better.

JOB SUMMARY

Apptronik is building robots for the real world — to improve human quality of life and help solve the ever-increasing labor shortage. As a Controls Engineer – Actuation on our Controls team, you will own both the actuator models that make our simulation trustworthy and the actuator-level control that runs on real hardware — closing the loop from bench characterization and system identification, through simulator integration, to controller design, tuning, and deployment. You will pair deep motor electromechanics and system-identification skill with strong C++/Python engineering, working hand in hand with our Controls, Firmware, and Simulation teams so that both model fidelity and control performance are driven by how they are actually used on the robot.

ESSENTIAL DUTIES AND RESPONSABILITIES or KEY ACCOUNTABILITIES

• Develop and maintain high-fidelity actuator models in simulation, capturing the physical behaviors (friction, compliance, thermal, torque and current limits) that meaningfully affect real-world performance.
• Design, tune, and deploy actuator-level control — closed-loop torque and current control and the low-level control that turns commands into reliable joint behavior on hardware.
• Design and run hardware test campaigns to characterize actuator behavior and extract the parameters that keep both the models and the controllers accurate.
• Apply system identification to extract trustworthy physical models from experimental data, and use those models to inform controller design and gain selection.
• Quantitatively validate sim-to-real fidelity — for both the models and the controllers — using appropriate comparison metrics, and understand the limitations of each.
• Build and maintain robust Python/C++ tooling for experiment automation, model extraction, controller tuning, and simulator integration.
• Partner with the Controls team throughout — aligning on the fidelity and control performance actually needed, how model and controller choices ripple into training and policy performance, and where the actuator layer is the root cause of a sim-to-real gap.
• Support hardware bring-up and deployment, translating validated models and controllers into real robot configuration.

SKILLS AND REQUIREMENTS

• Strong C++, including comfort extending a simulator or physics-engine codebase — not just consuming one through a Python interface.
• Deep grounding in motor electromechanics and classical control — closed-loop torque/current control, controller design and tuning, and frequency-domain analysis (e.g. Bode plots, stability margins).
• Hands-on actuator or servo control on real hardware: designing, tuning, and validating low-level controllers, informed by system identification.
• Hands-on system identification and modeling: structured experiment design and model fitting from real data that feeds both simulation and control.
• Proficiency in Python (test automation, data analysis, tooling) and a track record shipping maintainable code under Git in a fast-moving R&D environment.
• Comfortable working cross-functionally with controls engineers — focused on how your models and controllers get used, not just whether they fit the data.
• Preferred: experience with dynamometers, motor test stands, and lab instrumentation; motor thermal modeling and gearbox efficiency / backlash characterization; real-time actuator communication protocols and embedded / firmware control; a modern robotics simulator (MuJoCo, Isaac Sim/Lab, Brax) and sim-to-real validation workflows; and Docker with GPU/cloud experiment infrastructure.

EDUCATION and/or EXPERIENCE

• BS in Robotics, ME, EE, CS, or a related field + 4 years of relevant experience; MS in a related field + 2 years of relevant experience; or a PhD in a related field.
• Prior humanoid or legged-robot experience is strongly preferred.

PHYSICAL REQUIREMENTS:

• Prolonged periods of sitting at a desk and working on a computer
• Must be able to lift 15 pounds at times
• Vision to read printed materials and a computer screen
• Hearing and speech to communicate

*This is a direct hire. Please, no outside Agency solicitations.

Apptronik provides equal employment opportunities to all employees and applicants for employment and prohibits discrimination and harassment of any type without regard to race, color, religion, age, sex, national origin, disability status, genetics, protected veteran status, sexual orientation, gender identity or expression, or any other characteristic protected by federal, state or local laws.

As set forth in Apptronik’s Equal Employment Opportunity policy,we do not discriminate on the basis of any protected group status under any applicable law.

If you believe you belong to any of the categories of protected veterans listed below, please indicate by making the appropriate selection.As a government contractor subject to the Vietnam Era Veterans Readjustment Assistance Act (VEVRAA), we request this information in order to measure the effectiveness of the outreach and positive recruitment efforts we undertake pursuant to VEVRAA. Classification of protected categoriesis as follows:

A \"disabled veteran\" is one of the following: a veteran of the U.S. military, ground, naval or air service who is entitled to compensation (or who but for the receipt of military retired pay would be entitled to compensation) under laws administered by the Secretary of Veterans Affairs; or a person who was discharged or released from active duty because of a service‑connected disability.

A \"recently separated veteran\" means any veteran during the three‑year period beginning on the date of such veteran's discharge or release from active duty in the U.S. military, ground, naval, or air service.

An \"active duty wartime or campaign badge veteran\" means a veteran who served on active duty in the U.S. military, ground, naval or air service during a war, or in a campaign or expedition for which a campaign badge has been authorized under the laws administered by the Department of Defense.

An \"Armed forces service medal veteran\" means a veteran who, while serving on active duty in the U.S. military, ground, naval or air service, participated in a United States military operation for which an Armed Forces service medal was awarded pursuant to Executive Order 12985.