# VRM vs Robot Models for Vbots
**Last Updated**: 2025-12-02
**Status**: Analysis and Recommendations
---
## 🎯 Key Question: Should Robots Use VRM Format?
### Short Answer: **No, robots should NOT use VRM format**
**Why:**
- **VRM is humanoid-only**: VRM format requires a standardized humanoid bone structure (head, spine, arms, legs, hands, feet)
- **Scout is not humanoid**: Scout is a wheeled robot with mecanum wheels, no humanoid bones
- **VRM specification**: Based on glTF 2.0 but requires VRM humanoid bone mapping
### When VRM Makes Sense:
- ✅ **Humanoid robots** (Unitree G1, Atlas, ASIMO-style)
- ✅ **Anthropomorphic robots** (Robbie from Forbidden Planet - humanoid shape)
- ✅ **VTuber avatars** (VRoid Studio output)
- ✅ **VRChat human avatars**
### When VRM Does NOT Make Sense:
- ❌ **Wheeled robots** (Scout, Scout E)
- ❌ **Quadrupeds** (Unitree Go2 - has legs but not humanoid structure)
- ❌ **Non-humanoid robots** (drones, arms, custom robots)
---
## 📦 Recommended Formats for Robot Vbots
### For Unity3D/VRChat:
1. **FBX** (`.fbx`) - **BEST CHOICE**
- Industry standard
- Supports animations, materials, textures
- Unity native support
- VRChat compatible
2. **GLB** (`.glb`) - **MODERN ALTERNATIVE**
- Based on glTF 2.0
- Single file (includes textures)
- Web-friendly
- Unity supports via glTF importer
3. **OBJ** (`.obj`) - **SIMPLE FALLBACK**
- Basic mesh only
- No animations
- No materials (separate MTL file)
- Use only if nothing else available
### For Resonite:
- **VRM** - ✅ Works (Resonite imports VRM directly)
- **GLB** - ✅ Works (Resonite imports GLB directly)
- **FBX** - ❌ Not directly supported (need to convert)
---
## 🤖 Creating Scout as Vbot
### Option 1: Use FBX/GLB (Recommended)
**Workflow:**
1. **Obtain/Create Scout Model**:
- Get from official sources (Pilot Labs, FCC filings)
- Create in Blender from specs (11.5×10×8 cm)
- Use Blender MCP to create from primitives
2. **Export to FBX**:
```python
# Using blender-mcp
blender_export(
format="fbx",
filepath="D:/Models/scout_model.fbx",
use_selection=True
)
```
3. **Import to Unity**:
- Drag FBX into `Assets/Models/`
- Unity auto-imports
- Create prefab
4. **Use with vbot_crud**:
```python
vbot_crud(
operation="create",
robot_type="scout",
platform="unity",
model_path="Assets/Models/scout_model.fbx",
position={"x": 0.0, "y": 0.0, "z": 0.0}
)
```
### Option 2: Create "Humanoid" Scout VRM (Not Recommended)
**Why this is problematic:**
- Scout has no humanoid bones (no head, arms, legs)
- Would need to "stretch" Scout to fit humanoid rig
- Would look weird and not represent actual Scout
- VRM validator would reject or warn
**If you really want VRM:**
1. Model Scout in Blender
2. Create humanoid armature (head, spine, arms, legs)
3. Map Scout mesh to humanoid bones (stretching required)
4. Export as VRM using Blender VRM add-on
5. **Result**: Weird humanoid-shaped Scout (not recommended)
---
## 🛠️ Current avatar-mcp Tools Analysis
### What avatar-mcp CAN Do:
- ✅ **Load VRM models** (`avatar_load`, `avatar_manager`)
- ✅ **Animate VRM avatars** (bone control, blend shapes)
- ✅ **Export to FBX/UnityPackage** (but NOT to VRM)
- ✅ **Manage VRM metadata**
### What avatar-mcp CANNOT Do:
- ❌ **Create VRM from scratch**
- ❌ **Convert non-humanoid models to VRM**
- ❌ **Export to VRM format** (only imports VRM)
- ❌ **Handle robot-specific models** (no robot bone structures)
---
## 🔧 Recommended Expansion: Robot Model Tools
### Option A: Expand avatar-mcp
**Add robot-specific tools:**
```python
# New tools needed in avatar-mcp
robot_model_load(
model_path: str,
robot_type: str, # "scout", "go2", "custom"
format: str # "fbx", "glb", "obj"
)
robot_model_export(
robot_id: str,
format: str, # "fbx", "glb", "vrm" (if humanoid)
output_path: str
)
robot_to_vrm_convert(
robot_model_path: str,
humanoid_rig: bool = False, # Create humanoid rig for VRM
output_path: str
)
```
### Option B: Add to robotics-mcp (Better)
**Create robot-specific model tools:**
```python
# In robotics-mcp
robot_model_import(
robot_type: str,
model_path: str,
format: Literal["fbx", "glb", "obj", "vrm"],
platform: Literal["unity", "vrchat", "resonite"]
)
robot_model_export(
robot_id: str,
format: Literal["fbx", "glb", "obj"],
output_path: str
)
robot_model_convert(
source_path: str,
source_format: str,
target_format: str,
target_path: str
)
```
**Why this is better:**
- Keeps robot-specific logic in robotics-mcp
- avatar-mcp stays focused on humanoid avatars
- Clear separation of concerns
---
## 🎨 Creating Scout Model: Recommended Workflow
### Step 1: Get/Create Scout 3D Model
**Using Blender MCP:**
```python
# Create Scout from primitives
blender_mesh(
operation="create_cube",
name="Scout_Body",
location=(0, 0, 0),
scale=(0.115, 0.10, 0.08) # 11.5×10×8 cm in meters
)
# Add wheels (cylinders)
blender_mesh(
operation="create_cylinder",
name="Scout_Wheel_FL",
location=(-0.05, 0.05, -0.04),
scale=(0.02, 0.02, 0.01) # Wheel dimensions
)
# ... repeat for 4 wheels
# Add camera (small cube)
blender_mesh(
operation="create_cube",
name="Scout_Camera",
location=(0.0575, 0, 0.02), # Front of robot
scale=(0.01, 0.01, 0.01)
)
```
### Step 2: Export to FBX
```python
blender_export(
format="fbx",
filepath="D:/Models/scout_model.fbx",
use_selection=False, # Export all
apply_modifiers=True
)
```
### Step 3: Use in Unity
```python
# Via vbot_crud
vbot_crud(
operation="create",
robot_type="scout",
platform="unity",
model_path="D:/Models/scout_model.fbx",
position={"x": 0.0, "y": 0.0, "z": 0.0},
scale=1.0
)
```
---
## 🎭 Special Case: Robbie from Forbidden Planet
**Robbie IS humanoid!** ✅
Robbie has:
- Humanoid shape (head, torso, arms, legs)
- Can be rigged with humanoid bones
- **CAN be converted to VRM**
**Workflow for Robbie VRM:**
1. Get Robbie 3D model (FBX/OBJ)
2. Import to Blender
3. Create humanoid armature
4. Rig Robbie mesh to armature
5. Export as VRM using Blender VRM add-on
6. Use with avatar-mcp tools
```python
# Robbie can use VRM!
vbot_crud(
operation="create",
robot_type="robbie",
platform="unity",
model_path="Assets/Models/robbie.vrm", # VRM format OK!
position={"x": 1.0, "y": 0.0, "z": 1.0}
)
```
---
## 📋 Summary & Recommendations
### For Scout (Wheeled Robot):
- ✅ **Use FBX/GLB format** (NOT VRM)
- ✅ **Use vbot_crud with `model_path`**
- ✅ **Create model in Blender** (use Blender MCP)
- ❌ **Don't try to make VRM** (not humanoid)
### For Robbie (Humanoid Robot):
- ✅ **Can use VRM format** (humanoid shape)
- ✅ **Use avatar-mcp tools** for VRM management
- ✅ **Or use FBX** (also works)
### For Unitree Go2 (Quadruped):
- ⚠️ **Technically not humanoid** (4 legs, no arms)
- ⚠️ **VRM might work** (if rigged as humanoid - weird)
- ✅ **Better: Use FBX** (preserves quadruped structure)
### For Unitree G1 (Humanoid):
- ✅ **Perfect for VRM** (humanoid with arms)
- ✅ **Use avatar-mcp VRM tools**
- ✅ **Or use FBX** (also works)
### Tool Expansion Needed:
**avatar-mcp expansion:**
- ❌ **NOT needed** for robot models (avatar-mcp is for humanoid avatars)
- ✅ **Keep as-is** (focused on VRM/humanoid avatars)
**robotics-mcp expansion:**
- ✅ **Add robot model import/export tools** (DONE)
- ✅ **Add robot model creation tool** (DONE - uses blender-mcp)
- ✅ **Support FBX/GLB/OBJ formats** (DONE)
- ✅ **Integrate gimp-mcp for textures** (DONE)
- ✅ **Optional: VRM export for humanoid robots only** (DONE)
**MCP Server Integration:**
- ✅ **blender-mcp**: For creating/editing 3D models, exporting FBX/GLB/OBJ
- ✅ **gimp-mcp**: For creating/editing textures and images
- ✅ **unity3d-mcp**: For importing models into Unity projects
- ✅ **avatar-mcp**: For VRM management (humanoid robots only)
---
## 🚀 Next Steps
1. ✅ **Create Scout FBX model** (using `robot_model_create` - automated with blender-mcp + gimp-mcp)
2. ✅ **Add robot model tools to robotics-mcp**:
- ✅ `robot_model_import` (FBX/GLB/OBJ/VRM)
- ✅ `robot_model_export` (FBX/GLB/OBJ)
- ✅ `robot_model_create` (automated creation via blender-mcp + gimp-mcp)
- ✅ `robot_model_convert` (format conversion via blender-mcp)
3. ✅ **Use FBX for Scout** (not VRM)
4. ✅ **Use VRM for Robbie** (humanoid, VRM works)
5. ✅ **Keep avatar-mcp focused** on humanoid avatars
6. ✅ **Integrate blender-mcp** for model creation/editing
7. ✅ **Integrate gimp-mcp** for texture creation/editing
---
**Austrian Precision**: Right tool for the right job - VRM for humans, FBX for robots! 🇦🇹🤖