Vehicle Specifications

Physical specifications of the AV2 platform.

Vehicle Overview 

The AV2 is built on a [vehicle platform base]. This section documents the key physical parameters used in the control algorithms.

Vehicle Dimensions — AV2 dimensions diagram

Physical Dimensions 

Note

The wheel base of 1.23 m is a critical parameter used in the steering controller. Verify this measurement on your specific vehicle.

Kinematic Parameters 

These parameters define the vehicle’s motion capabilities and are used by the planning and control algorithms.

Speed Limits 

Parameter	Value	Notes
Maximum Speed	5.0 m/s	~18 km/h
Typical Operating Speed	2.0-3.0 m/s	~7-11 km/h
Minimum Speed (DWA)	0.0 m/s	Can stop

Acceleration Limits 

Parameter	Value	Notes
Maximum Acceleration	2.0 m/s²	Forward
Maximum Deceleration	3.0 m/s²	Braking
Emergency Deceleration	5.0+ m/s²	Full brake

Steering Geometry 

Parameter	Value	Notes
Maximum Steering Angle	±28°	At wheels
Steering Ratio	~14:1	Wheel to road
Maximum Yaw Rate	1.0 rad/s	~57°/s
Minimum Turning Radius	~2.5 m	At max steering

Turning Radius Calculation 

The minimum turning radius is calculated from:

\[R_{min} = \frac{L}{\tan(\delta_{max})}\]

Where:

\(L\) = Wheel base (1.23 m)
\(\delta_{max}\) = Maximum steering angle (28°)

import math
wheel_base = 1.23  # meters
max_steering = 28  # degrees
min_radius = wheel_base / math.tan(math.radians(max_steering))
# Result: ~2.3 meters

Collision Geometry 

For obstacle avoidance, the vehicle is modeled with the following parameters:

Parameter	Value	Notes
Robot Radius	0.8 m	Circular approx
Safety Margin	0.3 m	Additional buffer
Effective Radius	1.1 m	For planning

For more precise collision checking:

Parameter	Value
Robot Length	2.0 m
Robot Width	1.5 m

Weight Distribution 

Location	Weight
Front Axle	TBD kg
Rear Axle	TBD kg
Total	TBD kg

Tire Specifications 

Parameter	Value
Tire Size	TBD
Tire Pressure	TBD psi
Rolling Radius	TBD m

Configuration in Code 

These parameters are defined in the configuration files:

DWA Planner (config/dwa_config.yaml):

vehicle:
  max_speed: 5.0          # m/s
  max_yaw_rate: 1.0       # rad/s
  max_accel: 2.0          # m/s²
  max_yaw_rate_accel: 3.0 # rad/s²
  robot_radius: 0.8       # m

Pure Pursuit Controller (pure_pursuit_controller.py):

WHEEL_BASE = 1.23  # meters

Measurement Procedure 

To verify or update these parameters:

Wheel Base 

Place vehicle on level ground
Mark center of front wheel contact patch
Mark center of rear wheel contact patch
Measure distance between marks

Turning Radius 

Turn steering to full lock
Drive slowly in a circle
Measure radius to vehicle center

Weight 

Use vehicle scales under each wheel
Sum front wheels for front axle weight
Sum rear wheels for rear axle weight