Senior Mechanical Engineer

ESI Motion; Simi Valley (CA); On-site; USD 140,000 - 160,000; Full time

Benefits offered by this job

401(k)

401(k) matching

Flexible spending account

Health insurance

Health savings account

Life insurance

Vision insurance

Job summary

ESI Motion in Simi Valley, CA is seeking a Senior Mechanical Engineer (Actuators) to own the mechanical design of electromechanical actuators from concept through qualification and production. This is a hands-on senior IC role with CAD, analysis, bench work, and mentoring responsibilities. You'll report to the Director of Engineering and collaborate with electrical, controls, test, manufacturing, and supply chain teams.

Qualifications

• BS in Mechanical Engineering or closely related field.
• 7+ years of mechanical product development in aerospace/defense/high-reliability industries.
• Direct design responsibility for released actuators or similar motion-control hardware.
• Advanced SolidWorks skills with complex assemblies.

Responsibilities

• Lead mechanical architecture and detailed design of rotary and linear actuators, including housings, geartrains, bearings, shafts, brakes, seals, and interfaces.
• Translate customer and system requirements into actuator-level requirements and verification plans.
• Run sizing and trade studies for torque, speed, stiffness, backlash, efficiency, life, mass, and thermal limits.
• Select bearings, gears, lubricants, materials, coatings, and seals for vacuum and extreme environments.
• Perform structural, thermal, fatigue, and bearing-life analyses and correlate with test results.
• Release drawings, BOMs, and specifications using GD&T per ASME Y14.5 with tolerance stack-ups.
• Plan and support development, acceptance, and qualification testing including thermal-vacuum and vibration; lead root-cause investigations.
• Collaborate with suppliers and manufacturing to move designs to production.
• Lead design reviews and mentor junior engineers and designers.

Skills

SolidWorks

GD&T

FEA

Prototype build

Thermal analysis

Structural analysis

Education

BS in Mechanical Engineering

Tools

ASME Y14.5

FEA software

Prototype development tools

Job description

Role: Senior Mechanical Engineer (Actuators)

Company: ESI Motion

Location: Simi Valley, CA (on-site)

Salary: $140,000 to $160,000 per year

About ESI Motion

ESI is a technology leader in cutting-edge servo motor controller technology for extreme environments. We specialize in designing and manufacturing rugged, high-performance motor control products for space, military, industrial, aviation, robotics, automotive, and agricultural industries. We are entering an exciting year of company expansion and are looking for talented and driven engineers to join our team.

The Role

You’ll own the mechanical design of electromechanical actuators for space, defense, and other extreme-environment applications, from concept through qualification and production. This is a hands-on senior individual contributor role. You’ll do the CAD, run the analysis, work with the hardware on the bench, and mentor other engineers along the way. You’ll report to Director of Engineering and work closely with the electrical, controls, test, manufacturing, and supply chain teams.

What You’ll Do

• Lead mechanical architecture and detailed design of rotary and linear actuators, including housings, geartrains, bearings, shafts, brakes, seals, and interfaces
• Turn customer and system requirements into actuator‑level requirements, design margins, and verification plans
• Run sizing and trade studies for torque, speed, stiffness, backlash, efficiency, life, mass, and thermal limits
• Select bearings, gears, lubricants, materials, coatings, and seals for vacuum, temperature extremes, shock, vibration, contamination control, and long‑life operation
• Perform structural, thermal, fatigue, and bearing‑life analyses (hand calcs and FEA) and correlate them with test results
• Release drawings, BOMs, and specifications using GD&T per ASME Y14.5, backed by tolerance stack‑ups
• Plan and support development, acceptance, and qualification testing, including thermal‑vacuum, vibration, shock, and life cycling, and lead root‑cause investigations when hardware doesn’t behave
• Work with suppliers and manufacturing to move designs from prototype to repeatable production
• Lead design reviews and technical discussions with customers and suppliers, and mentor junior engineers and designers

What You Need

• BS in Mechanical Engineering or a closely related field
• 7+ years of mechanical product development in aerospace, defense, space, robotics, or another high‑reliability industry
• Direct design responsibility for released actuators, gearboxes, precision mechanisms, or similar motion‑control hardware
• Advanced SolidWorks skills with complex assemblies and tightly packaged electromechanical hardware
• Strong command of GD&T, ASME Y14.5, and worst‑case and statistical tolerance analysis
• Experience with structural and thermal FEA
• Hands‑on experience with prototype build, test, and troubleshooting
• Knowledge of materials, coatings, heat treatments, tribology, vacuum‑compatible lubrication, corrosion control, and contamination‑sensitive design
• Familiarity with aerospace and defense environmental qualification, including vibration, shock, thermal‑vacuum or thermal cycling, and life‑cycle testing
• Must be a U.S. Person as defined by ITAR (U.S. citizen, lawful permanent resident, or protected individual)

Nice to Have

• MS in Mechanical Engineering
• Experience leading an actuator through environmental qualification and production release
• Working knowledge of motor, resolver or encoder, and brake interfaces
• 401(k)
• 401(k) matching
• Flexible spending account
• Health insurance
• Health savings account
• Life insurance
• Vision insurance

As part of the ESI Motion's commitment to this overall process as an Equal Employment Opportunity (“EEO”) Employer, we will ensure all aspects of employment, including recruitment, selection, job assignment, training, compensation, benefits, discipline, promotion, transfer, layoff, and termination processes remain free of illegal discrimination based upon race, color, religion, sex, sexual orientation, gender identity, national origin, disability, and protected veteran status. ESI Motion ensures all employment decisions are based only on valid job requirements.