Senior Motor Control Engineer

1X • San Carlos, CA

6d • $180,000 - $230,000

About The Position

The Senior Motor Control Engineer will own motor control for 1X’s REVO2 family of in-house permanent magnet synchronous motors and new motor designs, across quasi-direct-drive and geared joints throughout the NEO humanoid robot. The role covers designing, simulating, tuning, and validating control strategies that deliver accurate torque while keeping the robot quiet, smooth, backdrivable, and compliant within current, voltage, and thermal limits. The engineer will take controllers from models and simulation through dynamometer testing and full-robot validation, and define operating limits, fault reactions, and safe torque-off behavior.

The position works closely with electromagnetic design, electrical, controls, firmware, test, and manufacturing teams. Responsibilities include translating electromagnetic FEA results into control-oriented motor models, correlating models with dynamometer and robot data, and applying control findings to motor and drive revisions. The engineer owns product control implementation and collaborates with electrical and firmware engineers to bring control strategies, parameters, and supporting validation evidence into production.

The role is suited to a hands-on engineer with strong motor-control fundamentals and experience debugging across hardware, firmware, and controls. Successful team members combine control theory with bench work, use measurements to guide tuning, document controllers and test results, and prioritize safe, gentle, reliable robot motion.

Requirements

• Bachelor’s degree in Electrical Engineering, Controls, Mechatronics, Robotics, or a related field.
• At least 3 years of industry experience designing and tuning motor control on real hardware; level is based on depth and scope of ownership.
• Experience shipping field-oriented control with cascaded current, velocity, and position loops for PMSM or BLDC motors on hardware that reached production, a fielded fleet, or a formal validation program.
• Strong command of PMSM modeling in the dq frame, space-vector PWM, inverter non-idealities such as dead time and current sensing, ADC and PWM timing, and voltage limits.
• Hands-on experience with motor parameter identification and position sensor calibration, including encoder, Hall, or resolver calibration and commutation offset.
• Dynamometer experience measuring torque constant, efficiency, torque ripple, and loop response, and using the data to make control changes.
• Experience with controller modeling and simulation in MATLAB/Simulink or Python.
• Ability to read embedded C/C++ well enough to trace control behavior to the code.

Nice To Haves

• Torque and impedance control for robotic joints, quasi-direct-drive or geared actuators, backdrivability, and compliant physical interaction.
• Field weakening and MTPA on low-voltage drives, and thermal modeling and derating of small motors.
• Control-oriented motor modeling with FEA-derived plant models such as JMAG-RT, and co-simulation with an electromagnetic design team.
• Experience reducing torque ripple, cogging, and acoustic noise in servo or robotic actuators.
• Embedded firmware development in C/C++ on STM32, TI C2000, or similar platforms, including ISR timing, DMA, and ADC/PWM synchronization.
• EtherCAT or CAN FD at 1 kHz and above, and familiarity with real-time operating systems such as FreeRTOS or Zephyr.
• Functional safety experience with IEC 61508, ISO 13849, or IEC 61800-5-2, including STO, and familiarity with robot safety standards such as ISO 13482 and ISO 10218.
• Sensorless control and observer design.
• MS or PhD with research in motor drives or control.

Responsibilities

• Design and tune field-oriented control using space-vector PWM and cascaded current, velocity, and position loops for REVO2 motor variants.
• Deliver torque and impedance control modes that support backdrivability and compliant contact, and verify torque accuracy at the joint output.
• Develop a motor parameter identification process for resistance, inductances, flux linkage, inertia, and friction that runs on the dynamometer and scales to production units.
• Own encoder, Hall, and resolver calibration and commutation-offset procedures.
• Reduce torque ripple and acoustic noise using cogging and ripple compensation, feedforward, and friction compensation, with measurements on the dynamometer and robot.
• Optimize torque and speed on a low-voltage battery bus using field weakening, MTPA, and voltage-limit handling while respecting current and thermal limits.
• Define and validate fault detection and reactions for overcurrent, overvoltage, undervoltage, overtemperature, stall, and sensor loss, including safe torque-off behavior.
• Characterize control performance on dynamometers, including torque constant, efficiency maps, torque ripple, thermal behavior, and loop response; establish repeatable test methods and clear reports.
• Build and maintain control-oriented plant models using tools such as JMAG-RT, MATLAB/Simulink, or Python; correlate models with dynamometer and robot data and feed findings into motor and drive revisions.
• Take controllers from model and simulation through dynamometer testing and full-robot validation.
• Work with electromagnetic design, electrical, firmware, controls, test, and manufacturing teams to develop, validate, and productionize actuator control strategies.
• Debug issues at the hardware, firmware, and control boundary, and document controller behavior and validation evidence.

Benefits

• Comprehensive medical, dental, and vision coverage.
• Generous paid time off, company holidays, and parental leave.
• 401(k) plan with company match: 100% on the first 3% of contributions and 50% on the next 2%.
• Flexible Spending Accounts (FSA) and Health Savings Accounts (HSA) options.
• Commuter benefits for transit and parking.
• Short-term and long-term disability, and life insurance.
• Employee Assistance Program for mental health, financial, and personal support.
• Onsite snacks and catered lunches.

What This Job Offers

• Job Type: Full-time
• Career Level: Senior