Real-time 3D Collision Avoidance Method for Safe Human and Robot Coexistence
Bibliographic record
Abstract
A novel solution to the three-dimensional dynamic human-robot collision problem is presented. Sphere-based geometric models are used for the human and robot due to the efficiency of the distance computation. The collision avoidance algorithm searches for collision-free paths by moving the end-effector along a set of pre-defined search directions. An optimization method is employed to select the search direction that balances between the robot approaching its goal location, and maximizing the distances between the human and robot models. The optimization incorporates predictions of the motions of the robot and human to reduce the negative effects of a non-instantaneous robot time response. The robot prediction is based on a transfer function model of its experimental time response at the joint level. The human prediction is performed at the sphere level using the weighted mean of past velocities. Predicting at the sphere level eliminates the difficulty introduced by the limbs moving in different directions. After describing the collision avoidance algorithm, a human walking towards a moving Puma robot arm is simulated. Captured motion data is used to make the human motion realistic. Monte Carlo simulations using 1000 random human walking paths passing through the robot workspace are used to evaluate the algorithm. The algorithm prevented all collisions due to the robot. The algorithm is deterministic and efficient enough to be used in real-time. On a 1.8 GHz Pentium IV PC, a 40 Hz sampling rate was achieved
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.004 | 0.001 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".