Test Engineer, Dropbox

About You and The Role

Zipline builds and operates autonomous delivery systems that move critical goods reliably and safely. Dropbox is our customer-facing package-loading product that integrates mechatronics, sensors, electronics, access control, user interaction, and environmental protection so untrained users can hand off packages to our droids. Failures or slow service at Dropbox directly increase field escalations, maintenance cost, and delivery delays.

As a Senior Hardware Test Engineer on Dropbox, you will own mechanical-heavy test and validation for critical assemblies and system-level behaviors. You will develop the test methods, equipment, automation, and evidence needed to prove that Dropbox meets its functional, safety, reliability, environmental, and lifetime requirements.

This is a hands‑on individual‑contributor role spanning test strategy, fixture design, instrumentation, experimental execution, data analysis, and failure investigation. You will work closely with design engineers while maintaining independent judgment about test adequacy, product risk, and release readiness.

• Own end-to-end validation of Dropbox mechanisms, structures, enclosures, electromechanical assemblies, and mechanical interfaces from prototype through fleet deployment.
• Translate product requirements, hazard analyses, field conditions, customer workflows, and known failure modes into measurable test requirements and pass/fail criteria.
• Develop verification plans with clear coverage, traceability, sample sizes, margins, acceptance criteria, and exit gates.
• Design, analyze, build, commission, and maintain test stands, fixtures, environmental setups, automated cycle rigs, and representative system test articles.
• Select and integrate instrumentation such as load cells, torque sensors, displacement sensors, accelerometers, strain gauges, thermocouples, cameras, current sensors, and data‑acquisition hardware.
• Produce drawings, tolerance analyses, safety reviews, BOMs, assembly instructions, calibration procedures, and maintenance documentation for test equipment.
• Apply free‑body diagrams, hand calculations, tolerance analysis, kinematics, fatigue and wear models, and FEA to design test equipment and establish representative loading.
• Develop tests covering structural strength, mechanism performance, high‑cycle life, wear, ingress, contamination, corrosion, temperature, humidity, misuse, obstruction, package variation, installation variation, and fault recovery.
• Validate interactions among mechanical hardware, actuators, sensors, electronics, embedded controls, packages, users, and droids.
• Automate test execution, data collection, health monitoring, fault detection, and reporting using Python or equivalent tools.
• Define sample sizes, acceleration factors, confidence levels, and statistical acceptance criteria that produce defensible reliability evidence.
• Correlate bench and accelerated tests with field telemetry, returned hardware, service records, and observed environmental conditions.
• Identify gaps between laboratory tests and field failures, then update test profiles to improve fidelity.
• Lead structured failure investigations using physical inspection, teardown, dimensional measurements, logs, instrumentation, and fault‑tree methods.
• Distinguish product failures from fixture, instrumentation, software, setup, and operator‑induced failures.
• Partner with Mechanical, Electrical, Embedded Software, Systems, Reliability, Manufacturing, Operations, and Safety to drive failures to root cause and permanent corrective action.
• Establish regression tests that detect hardware and software changes affecting mechanism performance, safety, or reliability.
• Present test evidence, unresolved risks, and release recommendations clearly during design and readiness reviews.
• Work directly with suppliers and manufacturing partners to validate components, tooling, processes, and production changes.
• Mentor engineers and technicians in fixture design, instrumentation, experimental methods, test execution, and failure analysis.
• Improve test throughput, repeatability, automation, lab utilization, and failure‑to‑answer time.

• Prove…