Encountering problems with adding a 4-motor power system to the vehicle

[欧阳逸云]

Hello everyone, this is my first time here and I am not familiar with the relevant posting rules. I apologize for any inconvenience caused.
I need to add an electric motor to each wheel of the vehicle to drive it independently. Currently, this is done as follows:

```

auto front_l_motor = chrono_types::make_shared<ChLinkMotorRotationSpeed>();

auto front_left_wheel = vehicle.GetWheel(0, VehicleSide::LEFT);

front_l_motor->Initialize(

front_left_wheel->GetSpindle(),

// vehicle.GetChassisBody(),

// vehicle.GetSteering(0)->GetSteeringLink(),

front_axle->m_suspension->GetSpindle(LEFT),

false,

front_left_wheel->GetPos(),

front_left_wheel->GetPos(),

ChVector3d(0, 1, 0),

ChVector3d(0, 1, 0)

);

vehicle.GetSystem()->Add(front_l_motor);

front_l_motor->SetSpeedFunction(chrono_types::make_shared<ChFunctionConst>(10.0));

```

```

driver.SetSteering(0.5); //Unable to turn

```

At present, the wheels can rotate normally, but it seems that the direction of the wheels is constrained, the steering control cannot be used, and the throttle is also ineffective. After multiple attempts and experiments, I still cannot solve this problem. I hope to receive help