Sensor Fusion & Control

SENSOR FUSION & CONTROL

Connecting Sensor Time, Coordinates, and State into One System

Autonomous mobile systems use data from DVS, RGB cameras, LiDAR/Depth, IMU, and Odometry, each with different update rates and coordinate systems. If these data are not aligned accurately, overall system decisions can become unstable even when each sensor operates correctly.

Robowink’s Sensor Fusion & Control research focuses on aligning heterogeneous sensor data to common time and coordinate references, combining them with mobility-state information, and creating consistent state representations and control interfaces for higher-level systems.

Research Scope
Sensor Fusion & Control is the integration layer that connects existing robot sensors and state information within a real autonomous mobile system.
DVS Event
RGB Camera
LiDAR / Depth
IMU / Odometry
→

Fusion & State Layer

Timestamp
Alignment
Coordinate
Transform
Confidence
Weighting
State
Estimation
→
Robot State
Trajectory / Motion
System Interface
Multi-Sensor Input → Alignment & Fusion → System State / Control Interface
TIME SYNCHRONIZATION

Aligning Sensor Time to a Common Reference

DVS event timestamps, camera frame times, LiDAR scan times, IMU samples, and robot-state update cycles are different. Before fusion, they must be aligned to a common time axis.

01 · ACQUIRE

Sensor Timestamp

Collects each sensor timestamp together with the system reception time.

02 · OFFSET

Clock Offset

Identifies time offsets caused by differences in sensor clocks and communication latency.

03 · BUFFER

Temporal Buffer

Maintains a recent data window in a buffer and matches sensor samples by time.

04 · ALIGN

Interpolation

Interpolates state values when necessary to construct sensor and mobility information for the same point in time.

05 · VALIDATE

Sync Quality

Flags data outside the allowed timing range or adjusts its fusion weight.

CALIBRATION & COORDINATE ALIGNMENT

Transforming Different Sensor Coordinates into a Common Reference

When sensors are mounted at different positions and orientations, the same object is observed in different coordinates. Extrinsic parameters and coordinate transforms are used to align observations into a common Robot Frame.

Coordinate Alignment DVS Frame T_robot←dvs LiDAR Frame T_robot←lidar IMU Frame Robot Frame common coordinate x · y · z · yaw Fusion aligned observations
CAL 01

Intrinsic Calibration

Calibrates camera and optical-system intrinsic parameters to reduce geometric distortion in image and event coordinates.

CAL 02

Extrinsic Calibration

Defines the mounting-position and orientation relationships of DVS, RGB, LiDAR, and IMU in a common reference frame.

CAL 03

Coordinate Transform

Transforms sensor observations consistently among Robot, Base, and Map Frames.

CAL 04

Alignment Validation

Compares sensor observations of the same object to check temporal and spatial alignment error.

FUSION STRATEGY

Fusion at the Data, Feature, or Decision Level

Rather than combining every sensor in the same way, we study architectures that select the fusion stage according to data characteristics, computational cost, and latency requirements.

LEVEL 01 · DATA

Early Fusion

Combines raw or low-level sensor data that can be aligned in time and coordinates into a common representation to preserve as much spatial and temporal information as possible.

LEVEL 02 · FEATURE

Mid-level Fusion

Combines ROI, motion features, depth, state vectors, and other features extracted from each sensor into a unified feature space.

LEVEL 03 · DECISION

Late Fusion

Maintains sensor-specific outputs and confidence values while applying weighted combinations or priority rules at the system level.

ROBOT STATE ESTIMATION

Interpreting Sensor Observations Together with Mobility State

External sensor information alone is not enough to fully understand the motion state of an autonomous mobile system. Internal states such as speed, heading, Odometry, IMU, and operating mode are combined to construct system context.

01

Pose / Odometry

Uses current position and displacement together with sensor observations to maintain spatial context.

02

Velocity / Heading

Combines vehicle speed and heading so the same external motion can be interpreted from a relative perspective.

03

IMU State

Uses acceleration and angular-velocity information to supplement short-term changes in orientation and motion state.

04

Operation Mode

Distinguishes the meaning of sensor data and interface conditions according to system modes such as driving, stopping, and task execution.

CONFIDENCE & ARBITRATION

Adjusting Confidence and Priority According to Sensor Condition

Sensor fusion requires more than simple averaging. The system must select which information to use based on sensor validity, environmental conditions, data freshness, and inference confidence.

SENSOR HEALTH

Quality & Confidence Monitoring

Detects conditions that reduce sensor reliability, such as missing data, delay, saturation, or increased noise, and reflects them in the fusion process.

  • Timestamp freshness
  • Signal / event quality
  • Sensor availability
  • Confidence normalization
ARBITRATION

Adaptive Weighting & Fallback

When the reliability of a particular sensor decreases, the weighting of other sensors and mobility-state information is adjusted to maintain a usable system-state representation.

  • Confidence-based weighting
  • Sensor priority policy
  • Graceful degradation
  • Fault / status propagation
CONTROL INTERFACE

Delivering Fused State Information to the Real Mobility System

This research delivers fused results and mobility state through standardized interfaces that can be used by higher-level Motion Planners and Robot Controllers.

01

Fusion State

State information in a common coordinate frame

02

Validity Check

Confidence and freshness validation

03

Interface Layer

Message / register conversion

04

Robot Controller

Motion / system input

05

Feedback

State, error, and execution feedback

REAL-TIME INTEGRATION

System Interfaces for Real-Time Data Flow

We study an integrated architecture that manages data formats and update cycles among sensors, edge modules, and robot controllers while monitoring processing latency and data loss.

01 · MESSAGE

Unified Data Schema

Defines common fields required for fusion, including Timestamp, Frame ID, Pose, and Confidence.

02 · TRANSPORT

Communication Interface

Evaluates communication interfaces appropriate for the target system, including Ethernet, CAN-class, and Serial.

03 · BUFFER

QoS / Queue

Manages queues and buffers according to data rate and priority so stale data does not remain in the control path.

04 · DIAGNOSTIC

Logging & Replay

Stores sensor, fusion, and control-interface logs and replays the same situations to analyze integration issues.

SYSTEM EVALUATION

Sensor Fusion & Control Evaluation Criteria

Evaluation focuses on how accurately multiple data sources are aligned and how reliably they are delivered in the actual system, rather than on individual sensor performance alone.

Time Sync
Time Alignment
Evaluation of inter-sensor timestamp offset and data freshness
Spatial Error
Spatial Alignment
Evaluation of common-coordinate transformation error among sensor observations
Fusion Latency
Fusion Latency
System processing time from input acquisition to fused-state generation
Interface Stability
Interface Stability
Long-duration stability evaluation of communication latency, data loss, and state feedback
RESEARCH CONNECTION

Sensor → Intelligence → Hardware → System

Sensor Fusion & Control is the final integration layer that connects the preceding three research technologies to a real robotic system.

SENSOR

DVS Event Vision

Handles event sensing, calibration, preprocessing, and spatiotemporal data representation.

INTELLIGENCE

SNN Risk Intelligence

Converts event sequences into spike-based temporal features and AI inference information.

HARDWARE

Neuromorphic Edge

Executes SNN models on RISC-V/MCU, dedicated accelerators, and memory architectures.

SYSTEM

Sensor Fusion & Control

Aligns and fuses all sensor and state information and connects it to real mobility-system interfaces.

Sensor Fusion & Control

Research & Technical Collaboration


We welcome joint research and PoC opportunities in DVS, RGB, LiDAR, and IMU alignment, state estimation, real-time sensor fusion, and robot-system interfaces.