Section 59.1: Object search in a simulated home

"I found the mug, the chair, and a very convincing false positive under the sofa."

A Home Search Agent With Notes
Technical illustration for Section 59.1: Object search in a simulated home.
Figure 59.1A: Object search capstone overview: an agent in a simulated apartment must locate a named object using only egocentric camera observations, a language instruction, and a navigation policy, with the evaluation metric being steps-to-success across 50 randomized object placements.
Big Picture

Object search in a simulated home gives Capstone Projects a concrete systems role: connect semantic search, navigation, and memory through a single success metric. The section keeps asking what the agent observes, what it remembers or updates, which action changes, and what evidence would convince a skeptical reader.

This section develops the technical contract for object search in a simulated home into a usable mental model. First we define the object of study, then we connect it to the agent loop, then we test it with a compact implementation.

The key question in Object search in a simulated home is practical: what must the agent know, what can it observe, what action is available, and what evidence shows that the action worked under the stated conditions?

Action Is The Test

Object search in a simulated home should be judged by the action it improves. A section claim is strong when it names the decision, the measurement, and the failure mode before a larger model or simulator is introduced.

Theory

For Object search in a simulated home, the practical design rule is to make the interface inspectable before optimization begins: inputs, outputs, units, latency, bounds, and failure labels should all be visible in the saved artifact.

Mechanism

The mechanism in Object search in a simulated home is the contract between representation and action. Name what enters the module, what leaves it, which assumptions make that transformation valid, and which log would reveal a bad handoff.

Worked Example

For Object search in a simulated home, keep one concrete rollout in view. A sensor reading becomes an estimate, the estimate constrains an action, the action changes the world, and the next observation confirms or contradicts the assumption. The section's idea is useful only if it improves that loop.

Library Shortcut

Use Habitat or AI2-THOR style home navigation traces for this project. The implementation stack should preserve object query, room graph, camera frame, belief state, selected frontier or waypoint, collision event, and final object-found evidence in one replayable log.

Practical Recipe

  1. Write the observation, action, and success metric before choosing a model.
  2. Build a baseline that is simple enough to debug by inspection.
  3. Add the library implementation only after the baseline behavior is understood.
  4. Record failures as structured cases: perception error, state error, planning error, control error, or evaluation error.
  5. Run at least one perturbation test before trusting the result.
Common Failure Mode

The common mistake in Object search in a simulated home is to trust a component score before checking the closed-loop interface. The failure usually appears where state, timing, authority, or evaluation context crosses a module boundary.

Practical Example

A team using Object search in a simulated home starts by writing the task panel, not by picking the largest model. They keep a baseline run, a maintained-tool run, and a perturbation run in the same result folder. The comparison is accepted only when the action trace, metric, and failure labels come from one script.

Memory Hook

Treat object search in a simulated home like a control-room label. If the label does not tell a future debugger what moved, what sensed, or what failed, it is decoration rather than engineering knowledge.

Research Frontier

For Object search in a simulated home, the open research question is not whether a larger policy can produce a better demo. The sharper question is whether the method improves reliability across new scenes, new embodiments, delayed feedback, and rare failures under an evaluation protocol that another lab can reproduce.

Self Check

For Object search in a simulated home, can you name the observation, action, protected assumption, success metric, and one likely failure case? If any field is vague, rewrite the contract before adding model complexity.

Topic-Native Deepening

This capstone looks simple on the surface, find an object in a home, but it exercises nearly every embodied-system interface at once: semantic grounding, navigation, memory, and stopping logic. The core difficulty is that success depends on when the agent decides it has enough evidence to stop searching.

A capstone design should therefore avoid grading only final discovery. It should also measure false positives, wasted path length, collision budget, and how quickly the agent replans after negative evidence.

Why This Section Matters

Object search in a simulated home becomes teachable once the student can state the operative variables, the decision boundary, and the evidence artifact. The section should therefore be read together with Chapter 30 on navigation and Chapter 27 on active perception, where the same loop is developed from adjacent angles.

Formal Object

Let $T_{find}$ be time to discovery, $C$ collisions, $L$ path length ratio to an oracle, and $F$ false declarations. A simple capstone score is $J = \mathbb{1}[\text{found}] - \lambda_T T_{find} - \lambda_C C - \lambda_L L - \lambda_F F$.

The penalty terms prevent the project from gaming the task by rushing, colliding, or declaring success too early. Instructors should publish the weights and keep them fixed across all teams.

Algorithm: Design the object-search capstone loop
  1. Choose a simulator, such as Habitat or AI2-THOR, and define a fixed house panel.
  2. Implement a baseline policy with map memory and semantic object hypotheses.
  3. Add a learned perception or planning component only after the baseline can be debugged by replay.
  4. Log time to discovery, wrong declarations, collisions, and replan count on every episode.
  5. Submit one replay case where the agent had to recover from an early false belief.
Deliverables for the Object-Search Project
DimensionWhat To SpecifyWhy It Matters
Task contractTarget object set, house panel, sensor package, stopping ruleLets other teams run the same task.
BaselineHeuristic frontier exploration plus semantic memoryGives the project a debuggable floor.
ImprovementLearned detector, language query, or memory rerankerShows the real research contribution.
EvidenceReplay, metrics, and one failure caseMakes grading about systems evidence, not demo polish.
def validate_card(payload: dict[str, object]) -> dict[str, object]:
    assert payload, "payload must not be empty"
    return payload

# Minimal evidence card for object search.
card = {
    "houses": 12,
    "targets": ["mug", "remote", "towel"],
    "stop_rule": "declare found after 3 consistent views",
    "metrics": ["time_to_find", "false_declarations", "path_length_ratio"],
}
print(validate_card(card))
{'houses': 12, 'targets': ['mug', 'remote', 'towel'], 'stop_rule': 'declare found after 3 consistent views', 'metrics': ['time_to_find', 'false_declarations', 'path_length_ratio']}
Code Fragment 59.1.A summarizes the topic-specific evidence card for object search in a simulated home.

The expected output is a clear task card. If the stop rule is missing, the project is under-specified because success can be declared arbitrarily.

Library Shortcut

After the from-scratch contract is clear, the practical route uses Habitat, AI2-THOR, ROS 2, CLIP-style detectors, SAM 2, Hydra, Weights & Biases. The payoff is that standard interfaces, logging, batching, and replay support move from ad hoc glue code into maintained infrastructure, while the evidence schema stays the same.

Project Or Teaching Use

A good undergraduate or graduate team can finish this project with a small number of houses if the evidence protocol is strict. The interesting result often comes from failure clustering, for example repeated confusion between mugs and cups in cluttered kitchen shelves.

Research Frontier

The research extension is language-conditioned search under uncertainty: letting the user say 'find the blue mug I used this morning' and forcing the system to combine semantics, temporal memory, and exploration.

Expected Output Interpretation

For object search, the artifact should show whether search failed from perception miss, bad semantic prior, unreachable room, exploration budget, or a wrong stopping condition.

Key Takeaway
Exercise 59.1.1

Design a method-matched experiment for Object search in a simulated home. Specify the environment, observation schema, action interface, metric, and one perturbation that targets the section's core assumption.

Section References

Savva, M. et al. Habitat: A Platform for Embodied AI Research. ICCV, 2019.

Use for simulated navigation projects, reproducible scene tasks, and embodied evaluation loops.

Cadene, R. et al. LeRobot: State-of-the-art Machine Learning for Real-World Robotics in Pytorch. GitHub project and technical documentation, 2024.

Use for dataset conversion, policy training, and capstone projects built around open robot-learning workflows.

What's Next?

Next, carry the artifact contract from Object search in a simulated home into the following capstone and compare which embodiment, action interface, or evaluation risk changes.