gred-cozmo

Cozmo-GRED: Generative Robot Emotional Displays

This is a GPT-2-medium-based language model fine-tuned to generate robot behaviors given an emotion label. It is trained on emotion-behavior data collected from the Cozmo robot and produces textual descriptions of Cozmo's actions that align with the given emotion.

Model Details

Base Model: GPT-2 Medium
Model type: Causal Language Model
Inputs: Prompt of the form Emotion: <emotion> Behaviors:
Outputs: A text sequence representing Cozmo robot behaviors

Development code: https://github.com/bsu-slim/emro-gred-cozmo

Emotion Labels

This model was trained on 6 grouped emotions:

• anger_frustration
• confusion_sorrow_boredom
• disgust_surprise_alarm_fear
• interest_desire
• joy_hope
• understanding_gratitude_relief

How to Use

from transformers import AutoModelForCausalLM, AutoTokenizer
import torch

model_name = "bsu-slim/gred-cozmo" 

model = AutoModelForCausalLM.from_pretrained(model_name)
tokenizer = AutoTokenizer.from_pretrained(model_name, use_fast=False)  # use_fast=False recommended

device = torch.device("cuda" if torch.cuda.is_available() else "cpu")
model.to(device)
model.eval()

emotion = "joy_hope"
prompt = f"<|startoftext|>Emotion: {emotion} <|endoftext|> Behaviors:"
inputs = tokenizer(prompt, return_tensors="pt").to(device)

# Generate behaviors
output = model.generate(
    **inputs,
    max_new_tokens=50,
    do_sample=True,
    top_k=50,
    top_p=0.95,
    pad_token_id=tokenizer.eos_token_id
)

generated_text = tokenizer.decode(output[0], skip_special_tokens=True)
print(f"Input Emotion: {emotion}")
print("Generated Behavior:")
print(generated_text.split("Behaviors:")[1].strip())

---

Example Output
Input Emotion: joy_hope
Generated Behavior:

display_oled_face_image_face8_1 say_text_oh!_1_1 set_head_angle_45_1 drive_straight_100_50 display_oled_face_image_face8_1

Citation

@INPROCEEDINGS{11246523,
  author={Baral, Rista and Grenz, Bethany and Kennington, Casey},
  booktitle={2025 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS)}, 
  title={Recognizing and Generating Novel Emotional Behaviors on Two Robotic Platforms}, 
  year={2025},
  volume={},
  number={},
  pages={21503-21510},
  keywords={Training;Emotion recognition;Behavioral sciences;Robots;Intelligent robots},
  doi={10.1109/IROS60139.2025.11246523}}