Research Engineer/Senior Research Engineer, 3D Auto-Labeling and Data Flywheel

Plusai; Santa Clara (CA); On-site; USD 130,000 - 220,000; Full time

Benefits offered by this job

Catered free lunch

Unlimited snacks and beverages

401(k) plan

Job summary

PlusAI is seeking a Research Engineer or Senior Research Engineer to advance 3D obstacle auto-labeling for autonomous trucks. You will turn multi-sensor data into offline 3D labels and improve quality through data‑centric ML.

You will collaborate with modeling teams, scale labeling pipelines, and mentor junior engineers. This role is based in Santa Clara, CA with a competitive salary and benefits package.

Qualifications

• BS, MS, or PhD in Computer Science, Robotics, Electrical Engineering, or related field, or equivalent practical experience.
• Hands‑on experience developing and evaluating 3D perception methods (detection, tracking, sensor fusion) with PyTorch; strong 3D geometry and calibration fundamentals.
• Strong Python (NumPy, Pandas, SQL) and C++ experience; experience running large offline workloads with GPU batch inference.
• Foundations for data‑centric machine learning: training‑data composition, ground truth evaluation, and reducing annotation cost.
• Self‑driven with a strong sense of responsibility; for senior level, end‑to‑end system ownership and mentoring.

Responsibilities

• Develop and evaluate methods turning multi-sensor recordings into accurate 3D object labels offline.
• Raise label quality and reduce human review by fixing causes in models and sensor fusion; adapt offline perception methods for our vehicles.
• Build and operate labeling pipelines at fleet scale: batch GPU inference, data extraction, annotation‑tool integration, monitoring and cost.

Skills

3D perception

Python

C++

GPU batch

Ground truth

Education

CS/Robotics/EE degree

Tools

PyTorch

Ceres

GTSAM

OpenCV

Job description

PlusAI is a Physical AI company pioneering AI-based virtual driver software for factory-built autonomous trucks. Headquartered in Silicon Valley with operations in the United States and Europe, Plus was named by Fast Company as one of the World’s Most Innovative Companies. Partners including TRATON GROUP’s Scania, MAN, and International brands, Hyundai Motor Company, Iveco Group, Bosch, and DSV are working with Plus to accelerate the deployment of next‑generation autonomous trucks. If you’re ready to make a huge impact and drive the future of autonomy, Plus is looking for talented individuals to join its fast‑growing teams.

Improving the models that drive our trucks depends on a data flywheel: among petabytes of fleet recordings, we curate the moments that matter, label them, train and evaluate onboard models, deploy, and collect again. Labeling is where this loop usually stalls, because human labeling does not scale with the fleet. Auto‑labeling closes that gap: offline models and compute, free of the vehicle’s real‑time limits, draft the labels, and people verify and correct only where it matters. This role focuses on 3D obstacle auto‑labeling: producing accurate 3D object labels from curated multi‑sensor recordings, at a quality that lets reviewers verify rather than draw and at a cost that scales. The underlying problems are general: fusing cameras and lidar into consistent 3D estimates, keeping objects consistent through time and occlusion, and knowing when a machine label is good enough. The role starts with 3D obstacles and can expand into other parts of the data flywheel over time.

We are open to candidates at either the Research Engineer or Senior Research Engineer level. Level will be determined by experience, technical depth, scope of responsibility and demonstrated impact. You do not need experience with every technology in our stack; we value strong fundamentals, a sense of responsibility and the ability to learn.

Responsibilities

• Develop and evaluate methods that turn multi-sensor recordings into accurate 3D object labels offline, using models and compute the vehicle cannot afford in real time, and measure them against reviewed ground truth

• Raise label quality and reduce the human review it needs: find where machine labels fail and fix the causes in models, sensor fusion or data; bring state‑of‑the‑art perception and foundation models into offline use and adapt them to our vehicles and sensors

• Build and operate the labeling pipelines at fleet scale: batch GPU inference, data extraction and alignment, selection of what goes to human review, annotation‑tool integration, monitoring, throughput and cost, and regression tests that catch quality drops before data reaches training

• Close the loop with the modeling teams: deliver training‑ready labels, feed model failures and long‑tail scenarios back into what gets curated and labeled next; at the senior level, lead designs and mentor

• Ensure that your work is performed in accordance with the company’s Quality Management System (QMS) requirements and contribute to continuous improvement efforts

Required Skills

• BS, MS, or PhD in Computer Science, Robotics, Electrical Engineering, or a related technical field, or equivalent practical experience

• Hands‑on experience developing and evaluating 3D perception methods (detection, tracking, sensor fusion or related) with a framework such as PyTorch, including experimentation, error analysis, principled metrics, built on solid fundamentals in 3D geometry, coordinate frames, and camera and lidar calibration

• Strong Python (NumPy, Pandas, SQL) and working C++ where performance matters; experience running large offline workloads with GPU batch inference

• Foundations for data‑centric machine learning: how training‑data composition shapes model behavior, how to evaluate against ground truth, and how to measure and reduce annotation cost

• Self‑driven with a strong sense of responsibility: a quick learner who takes problems from ambiguous to shipped; for the senior level, a system you were responsible for end to end, design documents others built on, and mentoring

Preferred Skills

• Auto‑labeling, offline perception, or ground‑truth generation for autonomous driving or robotics, including integrations with annotation tools and vendors

• Experience improving models through data: active learning and data flywheels, hard‑example mining, uncertainty or disagreement signals, dataset curation

• Lidar SLAM, structure‑from‑motion, factor‑graph optimization (GTSAM, Ceres), or stereo and monocular depth estimation

• Foundation and multimodal models: open‑vocabulary detectors, promptable segmentation, vision‑language models, embeddings and vector search

• Heavy‑truck specifics (articulated vehicles, trailer state estimation, multi‑platform calibration) or lane and road‑geometry labeling pipelines

$130,000 - $220,000 a year

Your opportunities joining PlusAI

Work, learn and grow in a highly future‑oriented, innovative and dynamic field.

Wide range of opportunities for personal and professional development.

Catered free lunch, unlimited snacks and beverages.

Highly competitive salary and benefits package, including 401(k) plan.