Implementation:CARLA simulator Carla VehicleControl

Knowledge Sources	CARLA
Domains	Vehicle Control, RPC Serialization
Last Updated	2026-02-15 05:00 GMT

Overview

VehicleControl is an RPC-serializable class that holds the standard vehicle control inputs: throttle, steer, brake, hand brake, reverse, manual gear shift, and gear selection.

Description

Defined in the carla::rpc namespace (~100 lines), this class represents the basic vehicle control interface with seven parameters:

• throttle (float, 0.0-1.0): engine throttle amount
• steer (float, -1.0 to 1.0): steering input
• brake (float, 0.0-1.0): brake pedal amount
• hand_brake (bool): hand brake engaged
• reverse (bool): reverse gear engaged
• manual_gear_shift (bool): manual transmission mode
• gear (int32_t): current gear number

The class supports MsgPack serialization, equality operators, and UE4 conversion to/from FVehicleControl when compiled within Unreal Engine.

Usage

Use this type to apply standard vehicle control commands (throttle/steer/brake) to vehicles via the CARLA client API.

Code Reference

Source Location

• Repository: CARLA
• File: LibCarla/source/carla/rpc/VehicleControl.h

Signature

namespace carla {
namespace rpc {

  class VehicleControl {
  public:
    VehicleControl() = default;
    VehicleControl(float throttle, float steer, float brake,
        bool hand_brake, bool reverse,
        bool manual_gear_shift, int32_t gear);

    float throttle = 0.0f;
    float steer = 0.0f;
    float brake = 0.0f;
    bool hand_brake = false;
    bool reverse = false;
    bool manual_gear_shift = false;
    int32_t gear = 0;

    bool operator!=(const VehicleControl &rhs) const;
    bool operator==(const VehicleControl &rhs) const;

    MSGPACK_DEFINE_ARRAY(throttle, steer, brake,
        hand_brake, reverse, manual_gear_shift, gear);
  };

} // namespace rpc
} // namespace carla

Import

#include "carla/rpc/VehicleControl.h"

I/O Contract

Field	Type	Default	Range	Description
throttle	float	0.0f	0.0 - 1.0	Engine throttle amount
steer	float	0.0f	-1.0 to 1.0	Steering input (left/right)
brake	float	0.0f	0.0 - 1.0	Brake pedal amount
hand_brake	bool	false	--	Hand brake engaged
reverse	bool	false	--	Reverse gear
manual_gear_shift	bool	false	--	Manual transmission mode
gear	int32_t	0	--	Current gear number

Usage Examples

#include "carla/rpc/VehicleControl.h"

carla::rpc::VehicleControl control;
control.throttle = 0.5f;    // half throttle
control.steer = -0.2f;      // slight left
control.brake = 0.0f;
control.hand_brake = false;
control.reverse = false;

// Apply control to vehicle actor
vehicle->ApplyControl(control);

Related Pages

• CARLA_simulator_Carla_VehicleAckermannControl
• CARLA_simulator_Carla_VehiclePhysicsControl
• Environment:CARLA_simulator_Carla_Simulation_Runtime