feat: SaltyRover 4-wheel diff-drive control loop (#74) #77

sl-webui · 2026-03-01T01:14:51-05:00

sl-webui commented

2026-03-01 01:14:51 -05:00

SaltyRover 4-wheel differential drive controller

Adds saltyrover_drive ROS2 package for the stable 4-wheel chassis. No balance PID needed — reuses /cmd_vel interface, Nav2, person_follower from main.

rover_drive_node

Tank-style kinematics: v_left = linear.x - angular.z × sep/2
FL/RL paired (same speed), FR/RR paired
Publishes /rover/wheel_speeds: {"cmd":"drive4","fl":N,"fr":N,"rl":N,"rr":N} (N ∈ [-1000, +1000])
Trapezoidal ramp: accel 2.0 m/s², decel 4.0 m/s²
cmd_vel watchdog (0.5s → zero)
max_speed 3.0 m/s (adjustable)

rover_odom_node

Dead-reckoning from /cmd_vel (encoder-ready for future HW)
Publishes /odom + TF odom→base_link
Forward Euler integration at 50 Hz

Tests: 52/52 passing

Kinematics, int scaling, JSON builder, full pipeline, ramp, odometry integration, quaternion conversion.

## SaltyRover 4-wheel differential drive controller Adds `saltyrover_drive` ROS2 package for the stable 4-wheel chassis. No balance PID needed — reuses /cmd_vel interface, Nav2, person_follower from main. ### rover_drive_node - Tank-style kinematics: `v_left = linear.x - angular.z × sep/2` - FL/RL paired (same speed), FR/RR paired - Publishes `/rover/wheel_speeds`: `{"cmd":"drive4","fl":N,"fr":N,"rl":N,"rr":N}` (N ∈ [-1000, +1000]) - Trapezoidal ramp: accel 2.0 m/s², decel 4.0 m/s² - cmd_vel watchdog (0.5s → zero) - max_speed 3.0 m/s (adjustable) ### rover_odom_node - Dead-reckoning from /cmd_vel (encoder-ready for future HW) - Publishes `/odom` + TF `odom→base_link` - Forward Euler integration at 50 Hz ### Tests: 52/52 passing Kinematics, int scaling, JSON builder, full pipeline, ramp, odometry integration, quaternion conversion.

sl-webui added 1 commit 2026-03-01 01:14:51 -05:00

feat: SaltyRover 4-wheel diff-drive control loop (#74 ) 4fed80f36d

Adds saltyrover_drive ROS2 package — 4-wheel differential drive controller
for the stable SaltyRover chassis (no balance PID required).

rover_drive_node:
  - Subscribes /cmd_vel (Twist), converts to left/right wheel speeds
  - Tank-style kinematics: v_left = linear.x - angular.z × sep/2
  - FL/RL share left speed, FR/RR share right speed (paired axles)
  - Publishes /rover/wheel_speeds (JSON: {"cmd":"drive4","fl":N,"fr":N,"rl":N,"rr":N})
  - Trapezoidal ramp: accel 2.0 m/s², decel 4.0 m/s² (stable chassis allows faster ramps)
  - cmd_vel watchdog (0.5s timeout → zero speeds)
  - max_speed 3.0 m/s (±1000 STM32 ticks)

rover_odom_node:
  - Dead-reckoning odometry from /cmd_vel (encoder-ready for future HW)
  - Publishes /odom (nav_msgs/Odometry) + TF odom→base_link
  - Forward Euler pose integration at 50 Hz

52/52 unit tests: kinematics, int scaling, JSON builder, full pipeline,
trapezoidal ramp, odometry integration, quaternion conversion.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

sl-jetson merged commit 165f5c174c into saltyrover-dev

2026-03-01 01:20:52 -05:00

sl-jetson referenced this issue from a commit

2026-03-01 01:20:53 -05:00

Merge pull request 'feat: SaltyRover 4-wheel diff-drive control loop (#74)' (#77) from sl-controls/rover-drive into saltyrover-dev

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Reference: seb/saltylab-firmware#77