Exemple #1
0
        public SpeedControlData GetCommandedSpeed()
        {
            double commandedSpeed = 0;
            double remainingDist  = distProvider.GetRemainingDistance();

            Services.Dataset.ItemAs <double>("requested stop distance").Add(remainingDist, curTimestamp);
            stopped = SpeedUtilities.GetStoppingSpeedCommand(remainingDist, baseSpeed, Services.StateProvider.GetVehicleState(), ref commandedSpeed);
            TrackingManager.TraceSource.TraceEvent(TraceEventType.Verbose, 0, "stop speed generator - remaining dist {0:F2}, base speed {1:F2}, commanded speed {2:F2}, stopped {3}", remainingDist, baseSpeed, commandedSpeed, stopped);

            return(new SpeedControlData(commandedSpeed, null));
        }
        public static void ComputeCommands(SpeedControlData data, OperationalVehicleState vs, out double commandedEngineTorque, out double commandedBrakePressure)
        {
            Services.Dataset.ItemAs <double>("commanded speed").Add(data.speed.GetValueOrDefault(-1), Services.CarTime.Now);

            // speed (m/s)
            double v = Math.Abs(vs.speed);

            double max_accel;

            if (!vs.IsInDrive)
            {
                // we're in reverse
                max_accel = 0.65;
            }
            else if (v < 10 * 0.44704)
            {
                // below 10 mph
                max_accel = 1.0;
            }
            else if (v < 15 * 0.44704)
            {
                // below 15 mph
                double coeff = (v - 10 * 0.44704) / ((15 - 10) * 0.44704);
                max_accel = 1.0 - coeff * 0.25;
            }
            else
            {
                max_accel = 0.75;
            }

            if (data.speed.HasValue && data.speed.Value <= 0 && (!data.accel.HasValue || data.accel.Value <= 0))
            {
                DateTime now = HighResDateTime.Now;
                if (zero_speed_time == DateTime.MinValue)
                {
                    zero_speed_time = now;
                }

                if (now - zero_speed_time < TimeSpan.FromMilliseconds(500) || v < 1)
                {
                    commandedEngineTorque  = 0;
                    commandedBrakePressure = TahoeParams.brake_hold;
                    return;
                }
            }
            else
            {
                zero_speed_time = DateTime.MinValue;
            }

            // desired speed (m/s)
            double rv = Math.Abs(data.speed.GetValueOrDefault(v));

            double d_err = 0;
            double err   = data.speed.HasValue ? v - rv : 0;

            if (data.speed.HasValue && !double.IsNaN(prev_err))
            {
                d_err = (prev_err - err) * Settings.TrackingPeriod;
                Services.Dataset.ItemAs <double>("speed - d error").Add(d_err, Services.CarTime.Now);
            }

            prev_err = err;

            // commanded acceleration (m / s^2)
            double ra = data.accel.GetValueOrDefault(0) - config.kp * (err) - config.ki * int_err + config.kd * d_err;

            // cap the maximum acceleration
            if (ra > max_accel)
            {
                ra = max_accel;
            }

            // add in the zero speed integral term
            ra += zero_speed_int * Math.Max(0, 1 - v / zero_speed_int_max_apply_speed);

            Services.Dataset.ItemAs <double>("requested acceleration").Add(ra, Services.CarTime.Now);

            // compute commands to achieve the requested acceleration and determine if we could achieve those commands
            bool couldAchieveRA = SpeedUtilities.GetCommandForAcceleration(ra, vs, out commandedEngineTorque, out commandedBrakePressure);

            // only accumulate integral error if we could achieve the target acceleration
            if (couldAchieveRA)
            {
                if (ra < max_accel && data.speed.HasValue)
                {
                    int_err *= config.ki_leak;
                    int_err += (err) * Settings.TrackingPeriod;
                    if (Math.Abs(int_err) > config.ki_cap)
                    {
                        int_err = Math.Sign(int_err) * config.ki_cap;
                    }
                }

                if (v < zero_speed_int_min_speed && ra > 0.2)
                {
                    zero_speed_int += zero_speed_int_rate * Settings.TrackingPeriod;
                }
            }

            if (v > zero_speed_int_reset_speed)
            {
                zero_speed_int = 0;
            }

            Services.Dataset.ItemAs <double>("speed - int error").Add(int_err, Services.CarTime.Now);
        }