Senior R&D Test Engineer

About RheoSense, Inc.

RheoSense, Inc. (RheoSense) is a leading scientific instrumentation company specializing in high‑precision microfluidic viscosity measurement technology. Our innovative VROC® platform is trusted by researchers, engineers, and scientists across biotechnology, pharmaceuticals, materials science, and advanced manufacturing.

We are committed to delivering accurate, reliable, and user‑friendly measurement solutions that empower our customers to accelerate discovery, improve product performance, and drive scientific advancement.

At RheoSense, we foster a collaborative, fast‑moving environment where innovation, continuous improvement, and customer focus guide everything we do. As we continue to grow, we’re looking for talented individuals who are excited to contribute to cutting‑edge technology and make a meaningful impact in the scientific community.

Position:  Senior R&D Test Engineer
Corporate Office:  San Ramon, California 
Relocation Assistance:  Relocation assistance is not available for this position. While qualified candidates from all locations are welcome to apply, preference may be given to candidates residing within a reasonable commuting distance or those who can relocate independently.
Closing:  Continuous Recruitment. We are accepting and reviewing all qualified applicants who meet the minimum requirements listed in this announcement for consideration on an ongoing basis.
Application Screening Process:  To ensure full consideration, applicants must meet the minimum qualifications for the position and complete all required application materials, including a current resume, detailed cover letter, pre-screen questionnaire, and video assessment. Incomplete applications may not be considered during the selection process.
Salary: The anticipated annual base salary range for this position is $150,000 to $190,000. The successful candidate's starting salary will be determined based on relevant skills, experience, qualifications, technical expertise, and other job-related factors. It is not typical for new hires to be placed at or near the top of the salary range.

Exceptional candidates with highly relevant scientific instrumentation, product testing, microfluidics, product development, or technical leadership experience may be considered above the posted range.

This position may also be eligible for discretionary performance-based incentive compensation, subject to individual and company performance.

Position Overview

RheoSense is seeking a highly experienced Senior R&D Test Engineer to lead the performance evaluation, reliability assessment, technical investigation, verification, and product testing activities associated with advanced scientific instrumentation and measurement technologies.

This role is intended for a senior-level engineer or scientist with significant experience in product development, scientific instrumentation, experimental design, engineering investigations, and multidisciplinary problem-solving. The successful candidate will play a critical role in identifying technical risks, developing test strategies, evaluating product performance, analyzing complex data, and driving product improvements through rigorous engineering investigation and evidence-based decision-making.

Unlike traditional test engineering roles that focus primarily on executing predefined procedures, this position requires an individual who can independently determine what should be tested, why it should be tested, and how meaningful engineering evidence should be generated to support product performance, reliability, manufacturability, and customer success.

Areas of Emphasis

The Senior R&D Test Engineer will provide technical leadership in:

• Scientific instrumentation and analytical measurement systems
• Product testing and performance characterization
• Verification and reliability engineering
• Failure analysis and technical investigations
• Experimental design and test method development
• Root-cause analysis and engineering troubleshooting
• Microfluidic systems and fluidics
• Optics, sensors, electronics, and precision electromechanical systems
• Product risk assessment and reliability evaluation
• Cross-functional product development support
• Data analysis and evidence-based engineering decision-making
• Mentoring and technical leadership of engineers and technicians
• Responsible use of AI-assisted engineering tools to improve productivity, technical analysis, and engineering effectiveness

Who You Are
You are a creative, resourceful, and highly detail-oriented engineer or scientist who enjoys understanding how scientific instruments and complex systems work, how they are used in real-world applications, and how they can fail. You possess a natural curiosity that drives you to ask questions, challenge assumptions, and investigate problems through systematic experimentation and data-driven analysis.

As a senior-level professional, you are recognized for your ability to independently lead complex engineering investigations, develop testing strategies, mentor technical staff, and influence product development decisions through sound engineering judgment and evidence-based recommendations.

You thrive in hands-on laboratory and engineering environments where you can design experiments, develop test methods, evaluate product performance, and solve multidisciplinary technical challenges. Rather than simply following established procedures, you enjoy determining what should be tested, why it should be tested, and how to generate meaningful evidence that supports product reliability, performance, and customer success.

You enjoy dissecting complex scientific instruments and systems to understand their underlying operating principles, intended use cases, limitations, and potential failure modes.

You combine hands-on experimentation with strong engineering judgment, enabling you to determine not only how to perform a test, but what should be tested, why it should be tested, and whether the resulting data provides meaningful evidence of product performance and reliability.

You are comfortable working across multiple technical disciplines and can quickly learn new concepts involving fluidics, mechanics, optics, sensors, materials, measurement systems, and scientific instrumentation.

Most importantly, you are motivated by continuous learning, scientific discovery, and the opportunity to influence product development through sound engineering judgment and experimental results.

This position offers broad exposure to product development, customer applications, engineering, and business operations. Individuals who demonstrate strong technical judgment, product insight, leadership capabilities, and the ability to translate customer and market needs into product improvements may have the opportunity to grow into Product Management, Technical Leadership, or Engineering Management roles.

Important: Scientific Instrumentation & Product Testing Role

This position is focused primarily on scientific instrumentation, experimental testing, reliability engineering, product performance evaluation, engineering investigations, and multidisciplinary engineering problem-solving.

While familiarity with software-controlled instruments, firmware-integrated systems, and data-analysis tools is beneficial, this is not a software development or software quality assurance role.

The most successful candidates will have substantial hands-on experience with laboratory environments, scientific instrumentation, hardware, product testing, engineering investigations, experimental design, and root-cause analysis. We are seeking individuals who can independently determine what needs to be tested, why it should be tested, and how to develop effective methods to evaluate product performance, reliability, and customer use cases.

The strongest candidates approach a new product or technical challenge by asking:

• How could this fail?
• What have we not tested?
• What assumptions are we making?
• How can we prove the product performs reliably under real-world conditions?
• What risks are customers likely to encounter that we have not yet evaluated?

The strongest candidate will combine scientific curiosity, disciplined testing, hands-on problem-solving, and the confidence to recommend design improvements based on experimental evidence.

Job Responsibilities and Expectations
This is not necessarily an all-inclusive list of job-related responsibilities, duties, skills, efforts, requirements, or working conditions. While this is intended to be an accurate reflection of the current job, management reserves the right to revise the job or to require that other or different tasks be performed as assigned.

1. Develop comprehensive test strategies, experimental protocols, and engineering evaluation plans for RheoSense products, subsystems, consumables, and new product features.
2. Translate product requirements, customer needs, and intended use cases into measurable test criteria.
3. Identify potential failure modes, technical risks, edge cases, and performance limitations through systematic engineering analysis and experimentation.
4. Design and execute hands-on testing involving fluidic systems, sensors, optics, mechanical assemblies, electronics, and integrated hardware/software systems.
5. Develop, improve, and maintain test fixtures, laboratory setups, sample-handling methods, measurement techniques, and experimental procedures.
6. Evaluate product performance, reliability, repeatability, robustness, accuracy, and usability under normal operating conditions and stressed-use scenarios.
7. Collect, organize, analyze, and interpret experimental data to support engineering decisions, product improvements, and root-cause investigations.
8. Troubleshoot product, process, and customer-related issues through structured root-cause analysis and engineering investigation.
9. Distinguish true product issues from experimental variation, measurement uncertainty, or test-method limitations.
10. Document test methods, protocols, observations, results, deviations, and conclusions in a clear, reproducible, and technically sound manner.
11. Collaborate closely with Engineering, Applications, Manufacturing, Quality, Software, Firmware, and Product Development teams.
12. Present findings, recommendations, risks, unresolved questions, and proposed corrective actions to project teams and management.
13. Identify opportunities to improve product performance, reliability, manufacturability, testability, and customer experience.
14. Utilize modern engineering tools, including AI-assisted technologies, to improve productivity in areas such as test planning, data analysis, documentation, troubleshooting, and technical evaluations.
15. Participate in design reviews and provide technical recommendations based on engineering analysis and test results.
16. Help establish and continuously improve structured testing and product evaluation practices for new and existing products.
17. Independently determine what should be tested, why testing is required, and the most effective methodology for generating reliable and actionable engineering evidence.
18. Provide technical leadership and mentorship to junior engineers, technicians, and cross-functional team members.
19. Lead complex product-testing, reliability, and failure-analysis initiatives supporting strategic product-development efforts.
20. Serve as a technical subject matter expert in product performance, product reliability, and engineering investigations.
21. Perform other duties and special projects as assigned.

Minimum Qualifications

• Bachelor's degree in Chemical Engineering, Mechanical Engineering, Optical Engineering, Biomedical Engineering, Bioengineering, Physics, Materials Science, Life Sciences, or a related scientific or engineering discipline.
• Ten (10) or more years of progressively responsible experience in product development, engineering, laboratory testing, scientific instrumentation, research, manufacturing, or related technical environments.
• Experience designing and executing experimental studies, test plans, engineering evaluations, or product-testing activities.
• Demonstrated ability to independently solve complex technical problems through structured investigation and root-cause analysis.
• Experience collecting, analyzing, and interpreting technical or scientific data to support engineering decisions.
• Hands-on experience working with laboratory equipment, measurement systems, instrumentation, or prototype testing environments.
• Experience preparing technical reports, test protocols, engineering documentation, and experimental records.
• Experience leading technical projects or cross-functional engineering initiatives.
• Ability to work effectively in a cross-functional environment and collaborate with Engineering, Manufacturing, Quality, and Operations teams.
• Strong written and verbal communication skills with the ability to clearly communicate technical concepts and findings.
• Proficiency with Microsoft Office applications and common engineering, scientific, or data-analysis tools.

Particularly Desirable Backgrounds Include

• Microfluidics and fluidic systems
• Plastics, polymers, and plastic-processing technologies
• Mechanical systems and precision mechanisms
• Optics and optical sensing
• Protein filtration, sample preparation, and characterization
• Rheology and viscosity measurement
• Electronics, sensors, and instrumentation
• Scientific instrumentation and analytical devices

Deep expertise in every area is not required. We value candidates who can learn quickly, think critically, connect concepts across disciplines, and apply engineering fundamentals to solve practical product-development and product-testing challenges.

AI and Modern Engineering Tools

We view responsible use of AI-assisted tools as an important component of modern engineering practice. Candidates should be comfortable leveraging AI technologies to improve productivity and effectiveness in activities such as:

• Developing test scenarios and edge-case analyses
• Reviewing requirements for completeness and traceability
• Organizing and analyzing test data
• Identifying trends and patterns in experimental results
• Drafting technical documentation and reports
• Supporting troubleshooting and root-cause investigations
• Evaluating potential design risks and testing gaps
• Accelerating engineering research and technical knowledge discovery

AI is expected to enhance engineering effectiveness but never replace scientific reasoning, engineering judgment, experimental rigor, or hands-on testing.

The successful candidate should demonstrate sound judgment regarding the appropriate use of AI tools and understand the importance of independently validating all technical conclusions, recommendations, and engineering decisions.

Physical Requirements
These physical requirements are not exhaustive, and additional job-related physical requirements may be added to these on an as-needed basis.

• This position is based onsite and requires regular presence in office, laboratory, and manufacturing environments.
• Ability to sit, stand, walk, and move throughout the facility during the course of the workday.
• Ability to use computers, testing equipment, instrumentation, and standard office equipment.
• Ability to handle and manipulate small mechanical and electronic components, test fixtures, and laboratory equipment.
• Ability to perform hands-on testing, troubleshooting, assembly, and evaluation activities requiring manual dexterity and visual attention to detail.
• Ability to occasionally lift, carry, and move materials, equipment, and test apparatus weighing up to 25 pounds.
• Ability to communicate effectively with colleagues, vendors, customers, and other stakeholders regarding technical and operational matters.
• Ability to safely work in laboratory and manufacturing environments while adhering to established safety procedures and requirements.

What We Offer

At RheoSense, you can build an excellent job that grows into a meaningful and rewarding career. Our comprehensive benefits and workplace culture include:

• Financial stability through competitive compensation, performance incentives, and retirement plans
• Training and professional development to support long‑term career growth
• Health and welfare benefits, including medical, dental, vision, life insurance, and wellness programs
• Paid Time Off (PTO) to support work–life balance
• Paid parental leave for both maternity and paternity
• 401(k) retirement savings plan with a company match of up to 4%
• Employee stock ownership (ISO) opportunities
• A collaborative, creative, inclusive, and engaging team environment

RheoSense is an equal‑opportunity employer and is committed to maintaining a diverse and inclusive workplace.