Abstract:
The drive inverter units that power the traction motors and steering motors of a manned or unmanned vehicle such as a mobile robot or automated guided vehicles (AGVs), industrial trucks or remote controlled vehicles that are equipped with a robot arm or other actuated mechanisms are also used to power the axes of the robot arms or other additional high power actuators (e.g. a lift table). The traction and steering motors can be disconnected from the drive and the motors of a robot arm or actuator can be connected to the drive and vice versa. The prerequisite is that driving and robot arm/actuator motion do not take place at the same time.

Description:
FIELD OF THE INVENTION 
       [0001]    This invention relates to mobile robots, automated guide vehicles (AGVs), industrial trucks or remote controlled vehicles that are equipped with a robot arm or other actuated mechanisms hereinafter referred to individually or collectively as a vehicle or vehicles be they manned or unmanned. 
       DESCRIPTION OF THE PRIOR ART 
       [0002]    The vehicle(s) each comprise electric motors for an actuated locomotion mechanism, that is, locomotion motors. Locomotion motors as used herein means one or more traction motors and may also, depending on vehicle type, include in addition to the one or more traction motors, one of more steering motors and one or more braking motors. The vehicle(s) also comprise electric motors for other actuators, a power supply and electric equipment for power distribution. Typical examples of power supplies are batteries, small combustion engines or inductive power transmission from the ground. Typical examples of a locomotion mechanism, include but are not limited to powered wheels, caterpillars, mecanum-wheels, and legs. 
         [0003]    Individual drive inverter units are used to power the traction and steering, that is locomotion, motors of the vehicle as well the axes of the robot arms or other additional high power actuators such as for example a lift table. 
       SUMMARY OF THE INVENTION 
       [0004]    A vehicle has two or more electric motors. One of the two or more motors is used for locomotion for the vehicle. All others of the two or more motors are used for other than locomotion of the vehicle with only one of the two or more motors in use at a given time. The vehicle also has at least one drive inverter unit for providing power to the two or more motors but only to that one of the two or more motors that is in use at the given time. 
         [0005]    A vehicle has a multiplicity of electric motors. A predetermined number of these motors are used to provide locomotion to the vehicle and all others of the multiplicity of electric motors used for other than locomotion of the vehicle. The vehicle also has a multiplicity of drive inverter units each for providing power to an associated one of the predetermined number of electric motors used to provide locomotion to the vehicle and to an associated one or more of the all others of the multiplicity of electric motors used for other than locomotion of the vehicle but at a given time each of the multiplicity of drive inverter units providing power only to either the associated one of the predetermined number of locomotion providing electric motors or to one of the associated one or more of the all other motors used for other than locomotion. 
         [0006]    A method for electrically powering a vehicle that has two or more electric motors with only one of the two or more motors in use at a given time and at least one drive inverter unit. In this method:
       one of the two or more motors is used for traction for the vehicle;   all others of the two or more motors are used for other than traction of the vehicle; and   the at least one drive inverter unit for delivering electric power to the two or more motors is shared between the two or more electric motors but the at least one drive inverter unit only delivering at a given time electric power to that one of said two or more motors that is in use at said given time.       
 
     
    
     
       DESCRIPTION OF THE DRAWING 
         [0010]      FIG. 1 a    shows a side view of one embodiment for a wheeled mobile robot. 
           [0011]      FIG. 1 b    shows a bottom view of the robot shown in  FIG. 1   a.    
           [0012]      FIG. 2 a    shows an embodiment for a wheeled vehicle that has a lift table. 
           [0013]      FIG. 2 b    shows a robot mounted on the lift table of the vehicle shown in  FIG. 2   a.    
           [0014]      FIG. 3  shows an embodiment wherein a mobile platform has wheels or caterpillars on articulated mechanisms. 
           [0015]      FIG. 4  shows an embodiment wherein a mobile platform has three or four omni-directional wheels that are mecanum wheels each with a traction motor. 
           [0016]      FIG. 5  shows an embodiment wherein the vehicle has legged mechanisms for locomotion. 
       
    
    
     DETAILED DESCRIPTION 
       [0017]      FIG. 1 a    shows a side view of one embodiment for a wheeled mobile robot  10  and  FIG. 1 b    shows a bottom view of mobile robot  10 . As shown in these figures, the mobile robot  10  has a mobile platform  8  that has two powered wheels  9  each with a traction motor  2  that may have an optional gearbox, differential steering, and one or more supporting casters  12 . While not shown in  FIGS. 1 a  and 1 b   , mobile robot  10  may optionally have one or more steering motors. 
         [0018]    Mobile robot  10  also has a drive inverter  5  and a switching unit  7  that is shown as side mounted in  FIG. 1 a    but can be located anywhere on robot  10 . The switching unit  7  may be integrated in the drive inverter  5  or a separate unit such as a relay. 
         [0019]    The switching unit  7  contains a relay type of switch that is rated to connect the power connections of a motor such as motor  2  or the other motors described below to the drive inverter  5 . Optionally the switching unit  7  may also contain an electromechanical (relay-type) or electronic switch for signal lines between the motor and the inverter drive  5 . Examples of signal lines are motor temperature output, motor hall sensor output, motor encoder output, motor tachometer output. 
         [0020]    Mobile robot  10  further has, as shown in  FIG. 1 a   , a robot  13  mounted on mobile platform  8 . Robot  13  has an arm  3  that has one or more joints, that is, actuated mechanisms  6 . Attached to the end of arm  3  is a tool  14  that can optionally have an actuatable mechanism at the attachment of tool  14  to arm  3 . 
         [0021]    The side mounted switching unit  7  connects only one of the motors described above to the power electronics (not shown) of the drive inverter  5 . Thus drive inverter  5  does not power two or more of these motors at the same time. 
         [0022]    Optionally the drive inverter  5  can store parameter sets and configuration data of two or more different motors and can switch between this data during runtime, provided that the connected motor is not moving. 
         [0023]    As shown in  FIG. 1 a   , mobile robot  10  which could be remotely controlled has mounted on it sensors  24  such as cameras or laser scanners. The sensors  24  provide data for the system, or to the operator of mobile robot  10  that the operator uses in his or her remote control of mobile unit  10 . 
         [0024]    Referring now to  FIG. 2 a   , there is shown another embodiment wherein there is mounted on mobile platform  8  a lift table  4  instead of robot  13 . Elements having reference numerals in  FIG. 2 a    that are identical to those shown in  FIGS. 1 a  and 1 b    have the same function as does the element in  FIGS. 1 a  and 1 b    and thus do not have to be described here in detail. In this embodiment, the drive inverter  5  is shared between the traction motors  2  and the motors of other actuated mechanisms such as the motor  6  for lift table  4 . 
         [0025]    Referring now to  FIG. 2 b   , there is shown an embodiment wherein a robot  15  is mounted on the lift table  4  that is mounted on mobile platform  8 . Elements having reference numerals in  FIG. 2 b    that are identical to those shown in  FIG. 2 a    have the same function as does the element in  FIG. 2 a    and thus do not have to be described here in detail. In this embodiment, the drive inverter  5  is shared between the traction motors  2  and the motors of other actuated mechanisms such as the motor  6  for lift table  4  and the motors for the arms of robot  15 . It should be appreciated that the inverter  5  can be shared between three or more motors that are not used at the same time by the use of the switching unit  7   b    
         [0026]    Referring now to  FIG. 3 , there is shown an embodiment wherein a mobile platform  16  has wheels or caterpillars on articulated mechanisms  23  that allow for better mobility in rough terrain. In this embodiment, the drive inverter  5  is shared between the motor  21  of the articulated mechanism  23  and the motors  26  of other attached mechanisms. As shown in  FIG. 3 , the other attached mechanism in this embodiment is a powered drill  25  and the motors  26  move drill up and down and backward and forward as shown by the arrows in  FIG. 3 . 
         [0027]    Referring now to  FIG. 4 , there is shown an embodiment wherein a mobile platform  17  has three or four omni-directional wheels, that is, mecanum wheels,  27  each with a traction motor  2 . A robot  15  is mounted on mobile platform  17 . In this embodiment, the drive inverters  5  are shared between the traction motors  2  and the motors of other actuated mechanisms such as the motors  6  for the axes of robot  15 . 
         [0028]    Referring now to  FIG. 5 , there is shown an embodiment wherein a vehicle  18  has legged mechanisms  29  for locomotion. While not shown in  FIG. 5 , the vehicle  18  may have combinations of wheels and legs for locomotion in place of legged mechanisms  29 . Elements having reference numerals in  FIG. 5  that are identical to those shown in  FIGS. 1 to 4  have the same function as does the element in  FIGS. 1 to 4  and thus do not have to be described here in detail. 
         [0029]    The vehicle  18  has an attached mechanism that is a shooting device  19  with a gun  36  that optionally can have a pan-tilt aiming mechanism  37 . The gun  36  can shoot a probe  35  or a sensor (not shown). It may be necessary to shoot or throw the probe  35  or sensor into or onto something that needs to be sensed. Examples are a vibration sensor with a magnet that is thrown onto a gearbox to record a noise pattern; or an oxygen sensor that is thrown into a sewage treatment basin to monitor the quality of purification; or a thermometer with a magnet that is thrown onto a pipe to measure its temperature. 
         [0030]    The gun  36  can be fired with pressurized air, e.g. by discharging a pressure tank  32 . Air is supplied to pressure tank  32  by an air compressor that has a regulated motor  31 . The probe  35  is either abandoned or recovered with a cord  34  that is uncoiled at the shot and coiled back on a pulley  33  for recovery. The cord  34  can also be used to host power supply and data lines to the probe  35 . 
         [0031]    The four drive inverters  5  shown in  FIG. 5  are shared between the motor  21  of the articulated mechanism  29  and the motors of the shooting device  19  and the motor  31 . The four drive inverters  5  can power either the articulated mechanism  29  which here are four legs or the other motors such as those used in the pump, pulley, pan, and tilt. This is only one example of many others possibilities of how the motors share the drive inverters  5 . 
         [0032]    It is to be understood that the description of the foregoing exemplary embodiment(s) is (are) intended to be only illustrative, rather than exhaustive, of the present invention. Those of ordinary skill will be able to make certain additions, deletions, and/or modifications to the embodiment(s) of the disclosed subject matter without departing from the spirit of the invention or its scope, as defined by the appended claims.