| Mapping |
The robot repeatedly avoids, approaches, or collides with the same wall section. |
The map contains duplicated walls, distorted geometry, missing space, or an incorrect obstacle position. |
Compare the live sensor scan with the stored map while the robot is stationary. |
Rebuild the map in a controlled environment. Keep the robot speed low during mapping and remove temporary obstacles. |
Map-to-scan alignment: stable overlap with no persistent double edges |
High |
| Mapping |
Doorways appear blocked or corridors are narrower than they are physically. |
Moving people, furniture, reflective surfaces, or sensor noise were recorded as permanent obstacles. |
Inspect the map for thin duplicate lines, isolated obstacle clusters, and inconsistent corridor widths. |
Map during a quiet period, increase filtering of transient returns, and verify the sensor mounting angle. |
Clearance margin remains greater than the robot footprint plus safety buffer |
Medium |
| Localization |
The robot position on the map slowly drifts away from its real position. |
Wheel-slip estimates, wheel-radius calibration, or wheelbase parameters are inaccurate. |
Drive a measured straight distance and compare odometry distance with the actual distance traveled. |
Calibrate wheel radius and wheel separation. Reduce reliance on wheel odometry when operating on slippery flooring. |
Odometry distance error is minimized over a measured test route |
High |
| Localization |
The robot suddenly jumps to a different location or rotates unexpectedly on the map. |
The localization algorithm has received an ambiguous or poor-quality sensor match. |
Review localization confidence, scan-matching residuals, and the pose estimate before and after the jump. |
Provide distinctive environmental features, improve initial pose estimation, and reject low-confidence corrections. |
Pose estimate changes smoothly without discontinuous jumps |
High |
| Localization |
Performance is reliable in one area but poor in large open spaces. |
Large open areas contain too few unique geometric features for reliable scan matching. |
Compare localization confidence in feature-rich rooms and feature-poor open areas. |
Use additional reliable positioning references, add static landmarks where practical, and limit high-speed motion. |
Localization confidence remains consistent across different environments |
Medium |
| Sensor Configuration |
The robot detects obstacles only at certain angles or misses low objects. |
The sensor field of view, mounting height, tilt, or blind zone does not cover the collision area. |
Place test objects at floor level and at several angles around the robot, then verify detection coverage. |
Correct the sensor pose, configure the minimum detection height appropriately, and add complementary sensing if required. |
Obstacle detection coverage includes the full collision envelope |
High |
| Sensor Quality |
Obstacle detection becomes unreliable near glass, mirrors, shiny floors, or dark surfaces. |
Some surfaces absorb, reflect, or redirect sensing energy and may produce weak or misleading returns. |
Repeat the same approach test using different surface materials and approach angles. |
Use sensor fusion, increase conservative obstacle margins, and validate the robot in the actual operating environment. |
False-negative obstacle detections are reduced during surface-specific tests |
High |
| Navigation |
The robot plans a route through a space that is visibly blocked. |
The costmap or obstacle layer is stale, incorrectly configured, or not receiving current sensor data. |
Confirm that newly introduced obstacles appear in the live costmap and that update timestamps are current. |
Check sensor topics, update rates, obstacle persistence settings, and the configured inflation layer. |
Obstacle-layer updates arrive continuously during motion |
High |
| Navigation |
The robot passes very close to walls even though the map is accurate. |
The obstacle inflation radius or robot footprint is smaller than the real physical clearance requirement. |
Compare the configured footprint and inflation distance with the measured robot dimensions and stopping distance. |
Use the complete footprint, add a safety margin, and account for localization and braking uncertainty. |
Planned clearance exceeds the required safety threshold |
High |
| Navigation |
The robot oscillates between left and right corrections near a wall. |
Controller gains, update frequency, trajectory scoring, or localization noise cause unstable corrections. |
Plot commanded velocity, measured pose, heading error, and obstacle distance during the oscillation. |
Retune controller gains, reduce speed near obstacles, and filter noisy pose updates without adding excessive delay. |
Heading and lateral errors converge without repeated sign changes |
Medium |
| Navigation |
The robot reaches the goal area but continues moving or touches nearby furniture. |
The goal tolerance is too large, the stopping distance is not modeled, or the final approach is poorly constrained. |
Measure the distance and heading error at the moment the navigation system reports success. |
Reduce goal tolerances where appropriate, add a controlled final-approach behavior, and verify braking performance. |
Final position and heading remain within validated tolerances |
Medium |
| Motion Control |
The robot appears safe at low speed but collides when traveling faster. |
Stopping distance, control latency, and sensor-processing delay increase the required safety margin. |
Measure stopping distance at multiple speeds on the actual floor surface. |
Limit velocity near obstacles and use a safety margin that includes detection, computation, and braking delays. |
Stopping distance remains shorter than available free space |
High |
| Coordinate Frames |
Obstacle locations are consistently offset from the robot or appear rotated. |
A transform between the sensor, robot base, odometry, or map frame is incorrect or delayed. |
Check frame names, axis directions, timestamps, sensor translation, and sensor rotation. |
Correct the frame transformation and verify it with a stationary sensor-target test. |
Static objects remain aligned across all active coordinate frames |
High |
| System Integration |
The robot behaves normally after startup but becomes unsafe after prolonged operation. |
Processing delays, dropped sensor messages, thermal throttling, or resource exhaustion reduce navigation responsiveness. |
Monitor CPU load, memory usage, message frequency, processing latency, and dropped-message counts. |
Reduce unnecessary workloads, optimize sensor processing, and configure a safe stop when data becomes stale. |
Sensor and control loop latency stays within the validated operating limit |
Medium |
| Safety Behavior |
The robot continues forward when obstacle data is unavailable or outdated. |
No fail-safe behavior is triggered when sensor communication or localization data becomes invalid. |
Disconnect or delay the relevant data stream in a controlled test and observe the robot response. |
Implement a watchdog, stale-data timeout, emergency stop path, and conservative fallback behavior. |
Robot stops or enters a safe state when critical data becomes invalid |
High |