p2os.cc

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/*
 *  P2OS for ROS
 *  Copyright (C) 2009
 *     Hunter Allen, David Feil-Seifer, Brian Gerkey, Kasper Stoy,
 *     Richard Vaughan, & Andrew Howard
 *
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 */
#include <termios.h>
#include <fcntl.h>
#include <string.h>
 
#include <ros/ros.h>
#include <p2os_driver/p2os.h>

P2OSNode::P2OSNode( ros::NodeHandle nh ) :
    n(nh), gripper_dirty_(false),
    batt_pub_( n.advertise<p2os_msgs::BatteryState>("battery_state",1000),
               diagnostic_,
               diagnostic_updater::FrequencyStatusParam( &desired_freq, &desired_freq, 0.1),
               diagnostic_updater::TimeStampStatusParam() ),
    ptz_(this)
{
    // Use sonar
    ros::NodeHandle n_private("~");
    n_private.param(std::string("odom_frame_id"), odom_frame_id,std::string("odom"));
    n_private.param(std::string("base_link_frame_id"), base_link_frame_id,std::string("base_link"));
    n_private.param("use_sonar", use_sonar_, false);
    
    // read in config options
    // bumpstall
    n_private.param( "bumpstall", bumpstall, -1 );
    // pulse
    n_private.param( "pulse", pulse, -1.0 );
    // rot_kp
    n_private.param( "rot_kp", rot_kp, -1 );
    // rot_kv
    n_private.param( "rot_kv", rot_kv, -1 );
    // rot_ki
    n_private.param( "rot_ki", rot_ki, -1 );
    // trans_kp
    n_private.param( "trans_kp", trans_kp, -1 );
    // trans_kv
    n_private.param( "trans_kv", trans_kv, -1 );
    // trans_ki
    n_private.param( "trans_ki", trans_ki, -1 );
    // !!! port !!!
    std::string def = DEFAULT_P2OS_PORT;
    n_private.param( "port", psos_serial_port, def );
    ROS_INFO( "using serial port: [%s]", psos_serial_port.c_str() );
    n_private.param( "use_tcp", psos_use_tcp, false );
    std::string host = DEFAULT_P2OS_TCP_REMOTE_HOST;
    n_private.param( "tcp_remote_host", psos_tcp_host, host );
    n_private.param( "tcp_remote_port", psos_tcp_port, DEFAULT_P2OS_TCP_REMOTE_PORT );
    // radio
    n_private.param( "radio", radio_modemp, 0 );
    // joystick
    n_private.param( "joystick", joystick, 0 );
    // direct_wheel_vel_control
    n_private.param( "direct_wheel_vel_control", direct_wheel_vel_control, 0 );
    // max xpeed
    double spd;
    n_private.param( "max_xspeed", spd, MOTOR_DEF_MAX_SPEED);
    motor_max_speed = (int)rint(1e3*spd);
    // max_yawspeed
    n_private.param( "max_yawspeed", spd, MOTOR_DEF_MAX_TURNSPEED);
    motor_max_turnspeed = (short)rint(RTOD(spd));
    // max_xaccel
    n_private.param( "max_xaccel", spd, 0.0);
    motor_max_trans_accel = (short)rint(1e3*spd);
    // max_xdecel
    n_private.param( "max_xdecel", spd, 0.0);
    motor_max_trans_decel = (short)rint(1e3*spd);
    // max_yawaccel
    n_private.param( "max_yawaccel", spd, 0.0);
    motor_max_rot_accel = (short)rint(RTOD(spd));
    // max_yawdecel
    n_private.param( "max_yawdecel", spd, 0.0);
    motor_max_rot_decel = (short)rint(RTOD(spd));
    
    desired_freq = 10;
    
    // advertise services
    pose_pub_ = n.advertise<nav_msgs::Odometry>("pose", 1000);
    //advertise topics
    mstate_pub_ = n.advertise<p2os_msgs::MotorState>("motor_state",1000);
    grip_state_pub_ = n.advertise<p2os_msgs::GripperState>("gripper_state",1000);
    ptz_state_pub_ = n.advertise<p2os_msgs::PTZState>("ptz_state",1000);
    sonar_pub_ = n.advertise<p2os_msgs::SonarArray>("sonar", 1000);
    aio_pub_ = n.advertise<p2os_msgs::AIO>("aio", 1000);
    dio_pub_ = n.advertise<p2os_msgs::DIO>("dio", 1000);
    
    // subscribe to services
    cmdvel_sub_ = n.subscribe("cmd_vel", 1, &P2OSNode::cmdvel_cb, this);
    cmdmstate_sub_ = n.subscribe("cmd_motor_state", 1, &P2OSNode::cmdmotor_state,
                                 this);
    gripper_sub_ = n.subscribe("gripper_control", 1, &P2OSNode::gripperCallback,
                               this);
    ptz_cmd_sub_ = n.subscribe("ptz_control", 1, &P2OSPtz::callback, &ptz_);
    
    veltime = ros::Time::now();
    
    // add diagnostic functions
    diagnostic_.add("Motor Stall", this, &P2OSNode::check_stall );
    diagnostic_.add("Battery Voltage", this, &P2OSNode::check_voltage );
    
    // initialize robot parameters (player legacy)
    initialize_robot_params();
}

P2OSNode::~P2OSNode()
{
}

void P2OSNode::cmdmotor_state( const p2os_msgs::MotorStateConstPtr &msg)
{
    motor_dirty = true;
    cmdmotor_state_ = *msg;
}

void P2OSNode::check_and_set_motor_state()
{
    if( !motor_dirty ) return;
    motor_dirty = false;
    
    unsigned char val = (unsigned char) cmdmotor_state_.state;
    unsigned char command[4];
    P2OSPacket packet;
    command[0] = ENABLE;
    command[1] = ARGINT;
    command[2] = val;
    command[3] = 0;
    packet.Build(command,4);
    
    // Store the current motor state so that we can set it back
    p2os_data.motors.state = cmdmotor_state_.state;
    SendReceive(&packet,false);
}

void P2OSNode::check_and_set_gripper_state()
{
    if( !gripper_dirty_ ) return;
    gripper_dirty_ = false;
    
    // Send the gripper command
    unsigned char grip_val = (unsigned char) gripper_state_.grip.state;
    unsigned char grip_command[4];
    P2OSPacket grip_packet;
    grip_command[0] = GRIPPER;
    grip_command[1] = ARGINT;
    grip_command[2] = grip_val;
    grip_command[3] = 0;
    grip_packet.Build(grip_command,4);
    SendReceive(&grip_packet,false);
    
    // Send the lift command
    unsigned char lift_val = (unsigned char) gripper_state_.lift.state;
    unsigned char lift_command[4];
    P2OSPacket lift_packet;
    lift_command[0] = GRIPPER;
    lift_command[1] = ARGINT;
    lift_command[2] = lift_val;
    lift_command[3] = 0;
    lift_packet.Build(lift_command,4);
    SendReceive(&lift_packet,false);
}

void P2OSNode::cmdvel_cb( const geometry_msgs::TwistConstPtr &msg)
{
    
    if( fabs( msg->linear.x - cmdvel_.linear.x ) > 0.01 || fabs( msg->angular.z-cmdvel_.angular.z) > 0.01 )
    {
        veltime = ros::Time::now();
        ROS_DEBUG( "new speed: [%0.2f,%0.2f](%0.3f)", msg->linear.x*1e3, msg->angular.z, veltime.toSec() );
        vel_dirty = true;
        cmdvel_ = *msg;
    }
    else
    {
        ros::Duration veldur = ros::Time::now() - veltime;
        if( veldur.toSec() > 2.0 && ((fabs(cmdvel_.linear.x) > 0.01) || (fabs(cmdvel_.angular.z) > 0.01)) )
        {
            ROS_DEBUG( "maintaining old speed: %0.3f|%0.3f", veltime.toSec(), ros::Time::now().toSec() );
            vel_dirty = true;
            veltime = ros::Time::now();
        }
    }
    
}

void P2OSNode::check_and_set_vel()
{
    if( !vel_dirty ) return;
    
    ROS_DEBUG( "setting vel: [%0.2f,%0.2f]",cmdvel_.linear.x,cmdvel_.angular.z);
    vel_dirty = false;
    
    unsigned short absSpeedDemand, absturnRateDemand;
    unsigned char motorcommand[4];
    P2OSPacket motorpacket;
    
    int vx = (int) (cmdvel_.linear.x*1e3);
    int va = (int)rint(RTOD(cmdvel_.angular.z));
    
    {
        // non-direct wheel control
        motorcommand[0] = VEL;
        if( vx >= 0 ) motorcommand[1] = ARGINT;
        else motorcommand[1] = ARGNINT;
        
        absSpeedDemand = (unsigned short)abs(vx);
        if( absSpeedDemand <= this->motor_max_speed )
        {
            motorcommand[2] = absSpeedDemand & 0x00FF;
            motorcommand[3] = (absSpeedDemand & 0xFF00) >> 8;
        }
        else
        {
            ROS_WARN( "speed demand thresholded! (true: %u, max: %u)", absSpeedDemand, motor_max_speed );
            motorcommand[2] = motor_max_speed & 0x00FF;
            motorcommand[3] = (motor_max_speed & 0xFF00) >> 8;
        }
        motorpacket.Build(motorcommand, 4);
        SendReceive(&motorpacket);
        
        motorcommand[0] = RVEL;
        if( va >= 0 ) motorcommand[1] = ARGINT;
        else motorcommand[1] = ARGNINT;
        
        absturnRateDemand = (unsigned short)abs(va);
        if( absturnRateDemand <= motor_max_turnspeed )
        {
            motorcommand[2] = absturnRateDemand & 0x00FF;
            motorcommand[3] = (absturnRateDemand & 0xFF00) >> 8;
        }
        else
        {
            ROS_WARN("Turn rate demand threshholded!");
            motorcommand[2] = this->motor_max_turnspeed & 0x00FF;
            motorcommand[3] = (this->motor_max_turnspeed & 0xFF00) >> 8;
        }
        
        motorpacket.Build(motorcommand,4);
        SendReceive(&motorpacket);
    }
}

void P2OSNode::gripperCallback(const p2os_msgs::GripperStateConstPtr &msg)
{
    gripper_dirty_ = true;
    gripper_state_ = *msg;
}

int P2OSNode::Setup()
{
    int i;
    int bauds[] = {B9600, B38400, B19200, B115200, B57600};
    int numbauds = sizeof(bauds);
    int currbaud = 0;
    sippacket = NULL;
    lastPulseTime = 0.0;
    
    struct termios term;
    unsigned char command;
    P2OSPacket packet, receivedpacket;
    int flags=0;
    bool sent_close = false;
    enum
    {
        NO_SYNC,
        AFTER_FIRST_SYNC,
        AFTER_SECOND_SYNC,
        READY
    } psos_state;
    
    psos_state = NO_SYNC;
    
    char name[20], type[20], subtype[20];
    int cnt;
    
    
    // use serial port
    
    ROS_INFO("P2OS connection opening serial port %s...",psos_serial_port.c_str());
    
    if((this->psos_fd = open(this->psos_serial_port.c_str(),
                             O_RDWR | O_SYNC | O_NONBLOCK, S_IRUSR | S_IWUSR )) < 0 )
    {
        ROS_ERROR("P2OS::Setup():open():");
        return(1);
    }
    
    if(tcgetattr( this->psos_fd, &term ) < 0 )
    {
        ROS_ERROR("P2OS::Setup():tcgetattr():");
        close(this->psos_fd);
        this->psos_fd = -1;
        return(1);
    }
    
    cfmakeraw( &term );
    cfsetispeed(&term, bauds[currbaud]);
    cfsetospeed(&term, bauds[currbaud]);
    
    if(tcsetattr(this->psos_fd, TCSAFLUSH, &term ) < 0)
    {
        ROS_ERROR("P2OS::Setup():tcsetattr():");
        close(this->psos_fd);
        this->psos_fd = -1;
        return(1);
    }
    
    if(tcflush(this->psos_fd, TCIOFLUSH ) < 0)
    {
        ROS_ERROR("P2OS::Setup():tcflush():");
        close(this->psos_fd);
        this->psos_fd = -1;
        return(1);
    }
    
    if((flags = fcntl(this->psos_fd, F_GETFL)) < 0)
    {
        ROS_ERROR("P2OS::Setup():fcntl()");
        close(this->psos_fd);
        this->psos_fd = -1;
        return(1);
    }
    // Sync:
    
    int num_sync_attempts = 3;
    while(psos_state != READY)
    {
        switch(psos_state)
        {
        case NO_SYNC:
            command = SYNC0;
            packet.Build(&command, 1);
            packet.Send(this->psos_fd);
            usleep(P2OS_CYCLETIME_USEC);
            break;
        case AFTER_FIRST_SYNC:
            ROS_INFO("turning off NONBLOCK mode...");
            if(fcntl(this->psos_fd, F_SETFL, flags ^ O_NONBLOCK) < 0)
            {
                ROS_ERROR("P2OS::Setup():fcntl()");
                close(this->psos_fd);
                this->psos_fd = -1;
                return(1);
            }
            command = SYNC1;
            packet.Build(&command, 1);
            packet.Send(this->psos_fd);
            break;
        case AFTER_SECOND_SYNC:
            command = SYNC2;
            packet.Build(&command, 1);
            packet.Send(this->psos_fd);
            break;
        default:
            ROS_WARN("P2OS::Setup():shouldn't be here...");
            break;
        }
        usleep(P2OS_CYCLETIME_USEC);
        
        if(receivedpacket.Receive(this->psos_fd))
        {
            if((psos_state == NO_SYNC) && (num_sync_attempts >= 0))
            {
                num_sync_attempts--;
                usleep(P2OS_CYCLETIME_USEC);
                continue;
            }
            else
            {
                // couldn't connect; try different speed.
                if(++currbaud < numbauds)
                {
                    cfsetispeed(&term, bauds[currbaud]);
                    cfsetospeed(&term, bauds[currbaud]);
                    if( tcsetattr(this->psos_fd, TCSAFLUSH, &term ) < 0 )
                    {
                        ROS_ERROR("P2OS::Setup():tcsetattr():");
                        close(this->psos_fd);
                        this->psos_fd = -1;
                        return(1);
                    }
                    
                    if(tcflush(this->psos_fd, TCIOFLUSH ) < 0 )
                    {
                        ROS_ERROR("P2OS::Setup():tcflush():");
                        close(this->psos_fd);
                        this->psos_fd = -1;
                        return(1);
                    }
                    num_sync_attempts = 3;
                    continue;
                }
                else
                {
                    // tried all speeds; bail
                    break;
                }
            }
        }
        switch(receivedpacket.packet[3])
        {
        case SYNC0:
            ROS_INFO( "SYNC0" );
            psos_state = AFTER_FIRST_SYNC;
            break;
        case SYNC1:
            ROS_INFO( "SYNC1" );
            psos_state = AFTER_SECOND_SYNC;
            break;
        case SYNC2:
            ROS_INFO( "SYNC2" );
            psos_state = READY;
            break;
        default:
            // maybe P2OS is still running from last time.  let's try to CLOSE
            // and reconnect
            if(!sent_close)
            {
                ROS_DEBUG("sending CLOSE");
                command = CLOSE;
                packet.Build( &command, 1);
                packet.Send(this->psos_fd);
                sent_close = true;
                usleep(2*P2OS_CYCLETIME_USEC);
                tcflush(this->psos_fd,TCIFLUSH);
                psos_state = NO_SYNC;
            }
            break;
        }
        usleep(P2OS_CYCLETIME_USEC);
    }
    if(psos_state != READY)
    {
        if(this->psos_use_tcp)
            ROS_INFO("Couldn't synchronize with P2OS.\n"
                     "  Most likely because the robot is not connected %s %s",
                     this->psos_use_tcp ? "to the ethernet-serial bridge device " : "to the serial port",
                     this->psos_use_tcp ? this->psos_tcp_host.c_str() : this->psos_serial_port.c_str());
        close(this->psos_fd);
        this->psos_fd = -1;
        return(1);
    }
    cnt = 4;
    cnt += snprintf(name, sizeof(name), "%s", &receivedpacket.packet[cnt]);
    cnt++;
    cnt += snprintf(type, sizeof(type), "%s", &receivedpacket.packet[cnt]);
    cnt++;
    cnt += snprintf(subtype, sizeof(subtype), "%s", &receivedpacket.packet[cnt]);
    cnt++;
    
    std::string hwID = std::string( name ) + std::string(": ") + std::string(type) + std::string("/") + std::string( subtype );
    diagnostic_.setHardwareID(hwID);
    
    command = OPEN;
    packet.Build(&command, 1);
    packet.Send(this->psos_fd);
    usleep(P2OS_CYCLETIME_USEC);
    command = PULSE;
    packet.Build(&command, 1);
    packet.Send(this->psos_fd);
    usleep(P2OS_CYCLETIME_USEC);
    
    ROS_INFO("Done.\n   Connected to %s, a %s %s", name, type, subtype);
    
    // now, based on robot type, find the right set of parameters
    for(i=0;i<PLAYER_NUM_ROBOT_TYPES;i++)
    {
        if(!strcasecmp(PlayerRobotParams[i].Class.c_str(),type) &&
                !strcasecmp(PlayerRobotParams[i].Subclass.c_str(),subtype))
        {
            param_idx = i;
            break;
        }
    }
    if(i == PLAYER_NUM_ROBOT_TYPES)
    {
        ROS_WARN("P2OS: Warning: couldn't find parameters for this robot; "
                 "using defaults");
        param_idx = 0;
    }
    
    //sleep(1);
    
    // first, receive a packet so we know we're connected.
    if(!sippacket)
    {
        sippacket = new SIP(param_idx);
        sippacket->odom_frame_id = odom_frame_id;
        sippacket->base_link_frame_id = base_link_frame_id;
    }
    /*
  sippacket->x_offset = 0;
  sippacket->y_offset = 0;
  sippacket->angle_offset = 0;
  
  SendReceive((P2OSPacket*)NULL,false);
*/
    // turn off the sonars at first
    this->ToggleSonarPower(0);
    // if requested, set max accel/decel limits
    P2OSPacket accel_packet;
    unsigned char accel_command[4];
    if(this->motor_max_trans_accel > 0)
    {
        accel_command[0] = SETA;
        accel_command[1] = ARGINT;
        accel_command[2] = this->motor_max_trans_accel & 0x00FF;
        accel_command[3] = (this->motor_max_trans_accel & 0xFF00) >> 8;
        accel_packet.Build(accel_command, 4);
        this->SendReceive(&accel_packet,false);
    }
    
    if(this->motor_max_trans_decel < 0)
    {
        accel_command[0] = SETA;
        accel_command[1] = ARGNINT;
        accel_command[2] = abs(this->motor_max_trans_decel) & 0x00FF;
        accel_command[3] = (abs(this->motor_max_trans_decel) & 0xFF00) >> 8;
        accel_packet.Build(accel_command, 4);
        this->SendReceive(&accel_packet,false);
    }
    if(this->motor_max_rot_accel > 0)
    {
        accel_command[0] = SETRA;
        accel_command[1] = ARGINT;
        accel_command[2] = this->motor_max_rot_accel & 0x00FF;
        accel_command[3] = (this->motor_max_rot_accel & 0xFF00) >> 8;
        accel_packet.Build(accel_command, 4);
        this->SendReceive(&accel_packet,false);
    }
    if(this->motor_max_rot_decel < 0)
    {
        accel_command[0] = SETRA;
        accel_command[1] = ARGNINT;
        accel_command[2] = abs(this->motor_max_rot_decel) & 0x00FF;
        accel_command[3] = (abs(this->motor_max_rot_decel) & 0xFF00) >> 8;
        accel_packet.Build(accel_command, 4);
        this->SendReceive(&accel_packet,false);
    }
    
    
    // if requested, change PID settings
    P2OSPacket pid_packet;
    unsigned char pid_command[4];
    if(this->rot_kp >= 0)
    {
        pid_command[0] = ROTKP;
        pid_command[1] = ARGINT;
        pid_command[2] = this->rot_kp & 0x00FF;
        pid_command[3] = (this->rot_kp & 0xFF00) >> 8;
        pid_packet.Build(pid_command, 4);
        this->SendReceive(&pid_packet);
    }
    if(this->rot_kv >= 0)
    {
        pid_command[0] = ROTKV;
        pid_command[1] = ARGINT;
        pid_command[2] = this->rot_kv & 0x00FF;
        pid_command[3] = (this->rot_kv & 0xFF00) >> 8;
        pid_packet.Build(pid_command, 4);
        this->SendReceive(&pid_packet);
    }
    if(this->rot_ki >= 0)
    {
        pid_command[0] = ROTKI;
        pid_command[1] = ARGINT;
        pid_command[2] = this->rot_ki & 0x00FF;
        pid_command[3] = (this->rot_ki & 0xFF00) >> 8;
        pid_packet.Build(pid_command, 4);
        this->SendReceive(&pid_packet);
    }
    if(this->trans_kp >= 0)
    {
        pid_command[0] = TRANSKP;
        pid_command[1] = ARGINT;
        pid_command[2] = this->trans_kp & 0x00FF;
        pid_command[3] = (this->trans_kp & 0xFF00) >> 8;
        pid_packet.Build(pid_command, 4);
        this->SendReceive(&pid_packet);
    }
    if(this->trans_kv >= 0)
    {
        pid_command[0] = TRANSKV;
        pid_command[1] = ARGINT;
        pid_command[2] = this->trans_kv & 0x00FF;
        pid_command[3] = (this->trans_kv & 0xFF00) >> 8;
        pid_packet.Build(pid_command, 4);
        this->SendReceive(&pid_packet);
    }
    if(this->trans_ki >= 0)
    {
        pid_command[0] = TRANSKI;
        pid_command[1] = ARGINT;
        pid_command[2] = this->trans_ki & 0x00FF;
        pid_command[3] = (this->trans_ki & 0xFF00) >> 8;
        pid_packet.Build(pid_command, 4);
        this->SendReceive(&pid_packet);
    }
    
    
    // if requested, change bumper-stall behavior
    // 0 = don't stall
    // 1 = stall on front bumper contact
    // 2 = stall on rear bumper contact
    // 3 = stall on either bumper contact
    if(this->bumpstall >= 0)
    {
        if(this->bumpstall > 3)
            ROS_INFO("ignoring bumpstall value %d; should be 0, 1, 2, or 3",
                     this->bumpstall);
        else
        {
            ROS_INFO("setting bumpstall to %d", this->bumpstall);
            P2OSPacket bumpstall_packet;;
            unsigned char bumpstall_command[4];
            bumpstall_command[0] = BUMP_STALL;
            bumpstall_command[1] = ARGINT;
            bumpstall_command[2] = (unsigned char)this->bumpstall;
            bumpstall_command[3] = 0;
            bumpstall_packet.Build(bumpstall_command, 4);
            this->SendReceive(&bumpstall_packet,false);
        }
    }
    
    // Turn on the sonar
    if(use_sonar_) {
        this->ToggleSonarPower(1);
        ROS_DEBUG("Sonar array powered on.");
    }
    ptz_.setup();
    
    return(0);
}

int P2OSNode::Shutdown()
{
    unsigned char command[20],buffer[20];
    P2OSPacket packet;
    
    if (ptz_.isOn())
    {
        ptz_.shutdown();
    }
    
    memset(buffer,0,20);
    
    if(this->psos_fd == -1)
        return -1;
    
    command[0] = STOP;
    packet.Build(command, 1);
    packet.Send(this->psos_fd);
    usleep(P2OS_CYCLETIME_USEC);
    
    command[0] = CLOSE;
    packet.Build(command, 1);
    packet.Send(this->psos_fd);
    usleep(P2OS_CYCLETIME_USEC);
    
    close(this->psos_fd);
    this->psos_fd = -1;
    ROS_INFO("P2OS has been shutdown");
    delete this->sippacket;
    this->sippacket = NULL;
    
    return 0;
}


void
P2OSNode::StandardSIPPutData(ros::Time ts)
{
    
    p2os_data.position.header.stamp = ts;
    pose_pub_.publish( p2os_data.position );
    p2os_data.odom_trans.header.stamp = ts;
    odom_broadcaster.sendTransform( p2os_data.odom_trans );
    
    p2os_data.batt.header.stamp = ts;
    batt_pub_.publish( p2os_data.batt );
    mstate_pub_.publish( p2os_data.motors );
    
    // put sonar data
    p2os_data.sonar.header.stamp = ts;
    sonar_pub_.publish( p2os_data.sonar );
    
    // put aio data
    aio_pub_.publish( p2os_data.aio);
    // put dio data
    dio_pub_.publish( p2os_data.dio);
    
    // put gripper and lift data
    grip_state_pub_.publish( p2os_data.gripper );
    ptz_state_pub_.publish( ptz_.getCurrentState() );
    
    // put bumper data
    // put compass data
    
}

/* send the packet, then receive and parse an SIP */
int P2OSNode::SendReceive(P2OSPacket* pkt, bool publish_data)
{
    P2OSPacket packet;
    
    if((this->psos_fd >= 0) && this->sippacket)
    {
        if(pkt)
            pkt->Send(this->psos_fd);
        
        /* receive a packet */
        pthread_testcancel();
        if(packet.Receive(this->psos_fd))
        {
            ROS_ERROR("RunPsosThread(): Receive errored");
            pthread_exit(NULL);
        }
        
        if(packet.packet[0] == 0xFA && packet.packet[1] == 0xFB &&
                (packet.packet[3] == 0x30 || packet.packet[3] == 0x31 ||
                 packet.packet[3] == 0x32 || packet.packet[3] == 0x33 ||
                 packet.packet[3] == 0x34))
        {
            
            /* It is a server packet, so process it */
            this->sippacket->ParseStandard( &packet.packet[3] );
            this->sippacket->FillStandard(&(this->p2os_data));
            
            if(publish_data)
                this->StandardSIPPutData(packet.timestamp);
        }
        else if(packet.packet[0] == 0xFA && packet.packet[1] == 0xFB &&
                packet.packet[3] == SERAUX)
        {
            // This is an AUX serial packet
            if(ptz_.isOn())
            {
                int len = packet.packet[2] - 3;
                if (ptz_.cb_.gotPacket())
                {
                    ROS_ERROR("PTZ got a message, but alread has the complete packet.");
                }
                else
                {
                    for (int i=4; i < 4+len; ++i)
                    {
                        ptz_.cb_.putOnBuf(packet.packet[i]);
                    }
                }
            }
        }
        else
        {
            ROS_ERROR("Received other packet!");
            packet.PrintHex();
        }
    }
    
    return(0);
}

void P2OSNode::updateDiagnostics()
{
    diagnostic_.update();
}

void P2OSNode::check_voltage( diagnostic_updater::DiagnosticStatusWrapper &stat )
{
    double voltage = sippacket->battery / 10.0;
    if( voltage < 11.0 )
    {
        stat.summary( diagnostic_msgs::DiagnosticStatus::ERROR, "battery voltage critically low" );
    }
    else if( voltage < 11.75 )
    {
        stat.summary( diagnostic_msgs::DiagnosticStatus::WARN, "battery voltage getting low" );
        
    }
    else stat.summary( diagnostic_msgs::DiagnosticStatus::OK, "battery voltage OK" );
    
    stat.add("voltage", voltage );
}

void P2OSNode::check_stall( diagnostic_updater::DiagnosticStatusWrapper &stat )
{
    if( sippacket->lwstall || sippacket->rwstall )
    {
        stat.summary( diagnostic_msgs::DiagnosticStatus::ERROR, "wheel stalled" );
    }
    else stat.summary( diagnostic_msgs::DiagnosticStatus::OK, "no wheel stall" );
    
    stat.add("left wheel stall", sippacket->lwstall );
    stat.add("right wheel stall", sippacket->rwstall );
}

void P2OSNode::ResetRawPositions()
{
    P2OSPacket pkt;
    unsigned char p2oscommand[4];
    
    if(this->sippacket)
    {
        this->sippacket->rawxpos = 0;
        this->sippacket->rawypos = 0;
        this->sippacket->xpos = 0;
        this->sippacket->ypos = 0;
        p2oscommand[0] = SETO;
        p2oscommand[1] = ARGINT;
        pkt.Build(p2oscommand, 2);
        this->SendReceive(&pkt,false);
        ROS_INFO("resetting raw positions" );
    }
}

/* toggle sonars on/off, according to val */
void P2OSNode::ToggleSonarPower(unsigned char val)
{
    unsigned char command[4];
    P2OSPacket packet;
    
    command[0] = SONAR;
    command[1] = ARGINT;
    command[2] = val;
    command[3] = 0;
    packet.Build(command, 4);
    SendReceive(&packet,false);
}

void P2OSNode::ToggleMotorPower(unsigned char val)
{
    unsigned char command[4];
    P2OSPacket packet;
    ROS_INFO( "motor state: %d\n", p2os_data.motors.state );
    p2os_data.motors.state = (int) val;
    command[0] = ENABLE;
    command[1] = ARGINT;
    command[2] = val;
    command[3] = 0;
    packet.Build(command, 4);
    SendReceive(&packet,false);
}

//  Actarray stuff

// Ticks to degrees from the ARIA software
inline double P2OSNode::TicksToDegrees (int joint, unsigned char ticks)
{
    if ((joint < 0) || (joint >= sippacket->armNumJoints))
        return 0;
    
    double result;
    int pos = ticks - sippacket->armJoints[joint].centre;
    result = 90.0 / static_cast<double> (sippacket->armJoints[joint].ticksPer90);
    result = result * pos;
    if ((joint >= 0) && (joint <= 2))
        result = -result;
    
    return result;
}

// Degrees to ticks from the ARIA software
inline unsigned char P2OSNode::DegreesToTicks (int joint, double degrees)
{
    double val;
    
    if ((joint < 0) || (joint >= sippacket->armNumJoints))
        return 0;
    
    val = static_cast<double> (sippacket->armJoints[joint].ticksPer90) * degrees / 90.0;
    val = round (val);
    if ((joint >= 0) && (joint <= 2))
        val = -val;
    val += sippacket->armJoints[joint].centre;
    
    if (val < sippacket->armJoints[joint].min)
        return sippacket->armJoints[joint].min;
    else if (val > sippacket->armJoints[joint].max)
        return sippacket->armJoints[joint].max;
    else
        return static_cast<int> (round (val));
}

inline double P2OSNode::TicksToRadians (int joint, unsigned char ticks)
{
    double result = DTOR (TicksToDegrees (joint, ticks));
    return result;
}

inline unsigned char P2OSNode::RadiansToTicks (int joint, double rads)
{
    unsigned char result = static_cast<unsigned char> (DegreesToTicks (joint, RTOD (rads)));
    return result;
}

inline double P2OSNode::RadsPerSectoSecsPerTick (int joint, double speed)
{
    double degs = RTOD (speed);
    double ticksPerDeg = static_cast<double> (sippacket->armJoints[joint].ticksPer90) / 90.0f;
    double ticksPerSec = degs * ticksPerDeg;
    double secsPerTick = 1000.0f / ticksPerSec;
    
    if (secsPerTick > 127)
        return 127;
    else if (secsPerTick < 1)
        return 1;
    return secsPerTick;
}

inline double P2OSNode::SecsPerTicktoRadsPerSec (int joint, double msecs)
{
    double ticksPerSec = 1.0 / (static_cast<double> (msecs) / 1000.0);
    double ticksPerDeg = static_cast<double> (sippacket->armJoints[joint].ticksPer90) / 90.0f;
    double degs = ticksPerSec / ticksPerDeg;
    double rads = DTOR (degs);
    
    return rads;
}

void P2OSNode::SendPulse (void)
{
    unsigned char command;
    P2OSPacket packet;
    
    command = PULSE;
    packet.Build(&command, 1);
    SendReceive(&packet);
}