Freelance Embedded Firmware Engineer Jobs in Missouri

At Motivo, Firmware Engineers are highly valued and versatile team members. They are the linchpin in executing complex embedded software projects from concept to validation. We look for creative problem-solvers with a keen eye for detail and the ability to balance competing priorities.

Working closely with a Project Manager, Electrical Engineers, and Systems Engineers, a Firmware Engineer guides focused engineering teams through the initial phases of product development. This involves:

• Planning technical and programmatic aspects of embedded software architecture.
• Defining and reviewing complete bare-metal or RTOS system architectures.
• Identifying and managing software risks, especially regarding real-time constraints and fault handling.
• Identifying key communication protocols and feedback sensor strategies.
• Leading technical teams to successful software integration and project completion.

In later phases, you'll lead brainstorms, conduct code reviews, provide technical guidance, and assist with debugging and troubleshooting during hardware-in-the-loop (HIL) testing and validation & verification (V&V) activities. An ideal candidate possesses a strong understanding of control theory, MCU interfacing, and motor control to effectively communicate and understand hardware-software interactions. This role is perfect for an incredibly sharp engineer with an insatiable curiosity for all aspects of engineering!

As a Firmware Engineer, you will:

• Architect and write bare-metal or RTOS-based firmware (C/C++) for custom MCUs to manage real-time motor control.
• Design, implement, and tune PID control loops (position, velocity, torque) for precise actuation across single and dual-motor configurations (500W to 5000W).
• Develop robust communication interfaces between the custom MCU and COTS motor drive PCBs, utilizing protocols such as CANopen, CAN‑FD, or Ethernet.
• Integrate, calibrate, and process data from high-resolution feedback sensors (e.g., resolvers, absolute/incremental encoders, Hall effect sensors).
• Implement state machines and diagnostic routines to ensure fail‑safe operation, supporting 1‑motor vs. 2‑motor redundancy architectures and fault‑tolerant communication.
• Partner with Hardware EEs to test MCU‑to‑COTS drive integrations, participating in hardware-in-the-loop (HIL) testing and dynamometer/test‑stand validation.
• Foster a culture of technical excellence and robust software V&V processes.

• Bachelor of Science in Computer Engineering, Electrical Engineering, Computer Science, Mechatronics, or a related field.
• 7+ years of professional experience in embedded software development (C/C++) for real‑time, safety‑critical systems.
• Deep understanding of motor control theory, real‑time servo control, and PID loop tuning.
• Hands‑on experience interfacing with COTS motor controllers and implementing CANopen (or similar fieldbus protocols).
• Experience with feedback sensor processing (resolvers, encoders) and digital signal filtering.
• Strong communication and interpersonal skills, with the ability to effectively collaborate with hardware teams and external clients.
• A passion for innovation and a desire to work in a fast‑paced, dynamic environment.

• Master of Science in a relevant engineering discipline.
• Experience in industries such as aerospace, electric vehicles (EV), or robotics.
• Familiarity with aerospace software standards (e.g., DO-178C) or automotive standards (e.g., ISO 26262).
• Experience with hardware‑in‑the‑loop (HIL) testing frameworks.
• A portfolio of successfully launched products featuring custom embedded motor control.

We’re convinced that the team and the projects are hands‑down the best part of working at Motivo. To support that, we offer a solid benefits package including high‑quality insurance, a 401(k) match, generous vacation time, and our Monday–Thursday 4/10 work week. We offer profit‑sharing bonuses, which are tied to overall company performance, because we believe in winning together; we’re transparent about the company’s numbers, and when our hard work drives financial success, employees may share in the upside.

Base Salary Range: $110,000 - $130,000

Salary is dependent on experience, knowledge and interview performance.