traj2csv.py

Trajectory to Speed Converter

Features

• Converts high-level trajectory commands to speed sequences

• Supports coordinated multi-servo movements

• Three movement profiles:

  • Linear (l): Constant acceleration

  • Smooth (s): Sinusoidal acceleration

  • Pulse (p): Instant change

• Maintains servo state between commands

• Comment support in trajectory files

Usage

python traj2csv.py INPUT.traj -o OUTPUT.csv

Trajectory Command Syntax

[CMD] [SERVOS] [VALUES] [DURATION_MS] [PROFILE]

• CMD: Movement type (mov or rot)

• SERVOS: Comma-separated servo IDs (e.g., x0,x2,x5)

• VALUES: Comma-separated target speeds (-100 to 100)

• DURATION_MS: Movement duration (ms)

• PROFILE: l (linear), s (smooth), or p (pulse)

Example Trajectory File

// Simultaneous movement with different profiles
mov x0,x1,x2 50,-30,80 2000 s
rot x5 100 500 p
mov all 0,0,0,0,0,0 1000 l

Output CSV Format

S1,S2,S3,S4,S5,S6
0.00,0.00,0.00,0.00,0.00,0.00
50.00,-30.00,80.00,0.00,0.00,0.00
...

---

Comparison Table

Feature	speed2csv.py	traj2csv.py
Command Type	Single movement	Multi-command sequence
Servo Coordination	Independent control	Coordinated movements
Profile Support	Per-servo profiles	Per-command profiles
Best For	Simple speed sequences	Complex trajectories
Input Format	Command-line args	Trajectory file
Output Resolution	20ms fixed	20ms fixed

---

Common Requirements

• Python 3.6+

• Required Libraries:

  pip install argparse csv-time
  

• CSV Compatibility:

  • Both generators create files compatible with the robot arm controller

  • Each row = 20ms of movement

  • Columns 1-6 = Servo 0-5 speeds (-100.00 to 100.00)

---

Execution Flow

1. Generate CSV using either tool:

   # Simple movement
   python speed2csv.py -s "100s 0 0 0 0 0" -t 1000 -o move.csv
   
   # Complex trajectory
   python traj2csv.py advanced.traj -o sequence.csv
   

2. Run on robot arm:

   python arm_controller.py sequence.csv
   

---

Note: Use --dry-run flag with the controller to validate CSVs without hardware movement