JP4411097B2 - Backup power supply for joint encoder of walking robot - Google Patents

Description

  The present invention relates to a power supply apparatus that supplies a main power source and a backup power source to a storage means for storing an output signal of an encoder such as an incremental encoder that detects a rotational position of a joint of a walking robot such as a humanoid robot.

  In walking robots, the joint positioning function of the encoder is maintained even after intentional power-off or power-off due to an unintended cause in order to facilitate appropriate control of joints such as legs after power-on. For this purpose, it is necessary to supply backup power even after the main power is turned off to the storage means for storing the output signal of the encoder. As a device for supplying such a backup power source, a device as shown in FIG. 3 for a movable shaft such as an NC machine tool or a robot described in Patent Document 1 is conventionally known.

  This power supply device is provided in a servo motor (not shown) that drives a movable shaft of a robot or the like, and has three diodes 32 to 34 for preventing backflow built in an absolute encoder 31 that detects the rotational position of the movable shaft, A capacitor 35 connected between the diodes 32 and 33, and a battery 38 incorporated in a control device 37 for controlling the operation of the servo motor and receiving rotational position information from the absolute encoder 31 via the signal line 36 are provided. It is.

  In this power supply device, the main power supply voltage Vcc output from the control device 37 generally connected to the commercial power supply is stored in a storage means (not shown) that is stored in the absolute encoder 31 and stores the detected rotation position. In addition to being supplied via the diodes 32 and 33, the backup power supply voltage Vbt of the battery 38 can be supplied to the storage means via the power supply line 40 and the diode 34, and further from the capacitor 35 charged via the diode 32. The main power supply voltage Vcc can be supplied to the storage means via the diode 33. In the figure, reference numeral 41 denotes a ground wire, and 42 denotes a relay connector.

In this power supply, however, the main power supply voltage Vcc and the backup power supply voltage Vbt are set to Vcc>Vbt> Vmm with respect to the operating voltage Vmm of the storage means. When the output of the voltage Vcc is stopped, the capacitor 35 first supplies the backup power to the storage means, and when the voltage drops below Vbt, the battery 38 supplies the backup power to the storage means. That is, double backup is performed without a switching control circuit.
JP 2001-251782 A

  By the way, in recent years, walking robots can be walked without connecting a power cable by obtaining main power from the battery installed in the walking robot itself, due to miniaturization and high efficiency of motors and batteries and advanced control. What can be used has been put into practical use.

  However, since the conventional power supply apparatus performs backup with the battery 38 with respect to the main power supply voltage Vcc obtained from the commercial power supply, the voltage difference between the main power supply and the backup power supply can be set relatively freely. Since the output voltage is determined by the specifications, even if the conventional power supply device is applied to a walking robot, a configuration in which main power and backup power are supplied from the main battery for operation mounted on the walking robot is established. There is a problem that backup cannot be performed for a long time because only backup from a spare battery is possible.

An object of the present invention is to advantageously solve the above problems, and a power supply device for a joint encoder of a walking robot according to the present invention stores an output signal of an encoder that detects a rotational position of a joint of the walking robot. In the power supply apparatus for supplying the main power source and the backup power source to the storage means, the main battery for supplying only the main power source and the backup power source respectively mounted on the walking robot, and lower than the output voltage of the main battery A backup battery having an output voltage higher than the voltage of the backup power supply, a first diode for connecting the main battery to the main power supply circuit and preventing a backflow of current to the main battery, and the backup power supply Connect a backup circuit to the supply circuit and reverse current flow to the backup circuit A second diode preventing a converter for backup output voltage of the second diode regulates the input voltage of the first diode output voltage from so as to the second lower diode, the backup circuit A third diode for connecting the main battery and preventing a backflow of current to the main battery side, and a fourth diode for connecting the backup battery to the backup circuit and preventing a backflow of current to the backup battery side And a battery converter that adjusts the input voltage of the third diode so that the output voltage of the fourth diode is lower than the output voltage of the third diode .

In such a power supply device for a joint encoder of a walking robot, a backup circuit is connected to a backup power supply circuit, and an output voltage of a second diode that prevents backflow of current to the backup circuit side is connected to the main power supply. Since the backup converter adjusts the input voltage of the second diode so as to be lower than the output voltage of the first diode that connects the main battery to the supply circuit and prevents the backflow of current to the main battery side, While the main power supply circuit supplies main power from the main battery via the first diode, the second diode does not supply backup power, and the main power supply circuit receives the first power from the main battery. When the main power supply is no longer supplied via the diode, the second diode automatically connects to the backup power supply from the backup circuit. I would like to supply.

And here, its backup circuit, lower than the output voltage of the main battery but with connecting spare battery output voltage higher than the voltage of the backup power supply, a fourth diode preventing the reverse flow of current to the spare battery side output voltage, the third output voltage to be lower than the diode for preventing reverse flow of the current to the main battery side with connecting main battery to the backup circuit, the input battery converter is a third diode Since the voltage is adjusted, the backup battery does not supply backup power via the fourth diode while the main battery supplies backup power via the third diode, and the main battery does not supply the third diode. The backup power supply voltage supplied via the spare battery is supplied via the fourth diode. Automatically, so to supply backup power to the backup circuit spare battery via a fourth diode becomes lower than the voltage of the backup power supply that.

  Therefore, according to the joint encoder power supply device for a walking robot of the present invention, even if the battery is the main power supply, when the main power supply is cut off, the main battery and the spare battery perform double backup without a switching control circuit. be able to. In addition, since the main power source and the backup power source are automatically switched and supplied from the main battery for operation mounted on the walking robot, the backup power source can be supplied for a longer period than when the backup battery alone is used.

  In the power supply device for joint encoder of the walking robot according to the present invention, a fifth power supply for connecting a commercial power supply to the backup circuit and preventing a reverse current flow to the commercial power supply side, and a fifth diode And a commercial power converter that adjusts the output voltage so as to be higher than the output voltage of the third diode and the output voltage of the fourth diode. While the power is supplied, when the main power is cut off, the backup power is first supplied from the commercial power supply, so that triple backup can be performed without a switching control circuit.

  Further, the power supply device for the joint encoder of the walking robot according to the present invention may comprise a charging means for charging the spare battery using the commercial power supply. In this way, the commercial power supply is supplied to the walking robot. Since the spare battery can be always charged using the commercial power source while the power is being used, the backup can be performed more reliably when the main power source is unintended.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of a power supply device for a joint robot of the walking robot according to the present invention, and FIGS. 2A and 2B are power supplies for the joint encoder of the walking robot of the above embodiment. It is the front view and side view which show the whole humanoid robot to which the apparatus is applied.

  As shown in FIGS. 2 (a) and 2 (b), the humanoid robot has two legs 2 under the body 1, and these legs 2 balance the dynamics in an inverted pendulum by a known method. While walking. This humanoid robot also has arms 3 on the left and right as viewed from the robot itself of the body 1 and a head 4 on the body 1, where the body 1 is front and back and left and right at the waist. The upper half 1a and the lower half 1b are connected so as to be rotatable.

  The humanoid robot is movable by reducing the servo motor and its output rotation on the leg 2, arm 3, head 4 and waist between the body 1 and the waist between the upper and lower halves 1a and 1b of the body 1, respectively. A plurality of joints (movable shafts) having a speed reducer for moving the parts, and the rotation positions of these joints are detected by an incremental encoder (not shown) provided in the joints and output as signals, A control device (not shown) housed in the upper half 1a is stored in an up / down counter 5 shown in FIG. 1 as a storage means having a normal memory. The control device includes a normal microcomputer and a motor driver. And a target rotation position of each joint obtained by calculation for an operation such as walking and the rotation position detected by the incremental encoder and stored in the up / down counter 5 Appropriately actuating the servo motor of each joint so as to reduce the deviation.

  The joint encoder power supply device of this embodiment supplies a PCI (peripheral device connection bus) power source (output voltage 5.2 V) as a main power source to the control device, and supplies the PCI power source to the up / down counter 5. It is mounted in the upper half 1a and the lower half 1b of the fuselage 1 for supplying a backup power supply (output voltage 5.0V). Specifically, as shown in FIG. A relatively large-capacity nickel-metal hydride battery 6 (output voltage 48 V) as a main battery for operation such as walking mounted on the lower half 1b, and a spare battery mounted on the upper half 1a of the fuselage 1 A relatively small capacity nickel cadmium battery 7 (output voltage 10.8 V) is provided.

  In the joint encoder power supply device of this embodiment, a nickel metal hydride battery 6 is connected to the PCI power supply circuit 8 mounted on the upper half 1a of the body 1 and the nickel metal hydride battery 6 side is connected. A diode 9 as a first diode for preventing a reverse current flow and a second diode for connecting a backup circuit 11 to the backup power supply circuit 10 and preventing a reverse current flow to the backup circuit 11 side. And a DC as a backup converter for adjusting the output voltages of the two diodes 9 and 12 to 5.2 V and 5.0 V, respectively, so that the output voltage of the diode 12 is lower than the output voltage of the diode 9. -The DC converters 13 and 14 and the backup circuit 11 A diode 15 as a third diode for connecting the Kell hydrogen battery 6 and preventing a backflow of current to the nickel hydrogen battery 6 side, and a nickel cadmium battery 7 connected to the backup circuit 11 and the nickel cadmium battery 7 A diode 16 as a fourth diode that prevents backflow of current to the side, and the output voltage of the diode 15 is adjusted to 13.0 V so that the output voltage 10.8 V of the diode 16 is lower than the output voltage of the diode 15 A DC-DC converter 17 serving as a battery converter, and a system switch 18 serving as a power switch interposed between the nickel-metal hydride battery 6 and the DC-DC converter 13.

  The joint encoder power supply device of this embodiment is further connected to the backup circuit 11 mounted on the upper half 1a of the body 1 and connected to the commercial power supply AC100V and prevents backflow of current to the commercial power supply side. And a commercial power converter for adjusting the output voltage of the diode 19 to 14.0 V so that the output voltage of the diode 19 is higher than the output voltage of the diode 15 and the output voltage of the diode 16. As an AC-DC converter 20, a temperature sensor 21 that measures the temperature of the nickel cadmium battery 7 and outputs the measurement result as a signal, and the nickel cadmium battery 7 is charged using the commercial power source and the temperature sensor 21 The temperature of the nickel cadmium battery 7 being charged based on the measurement result The charging control circuit 22 is provided as a charging means for controlling the charging current so as not to become too high. Here, the diodes 12, 15, 16, 19, the converters 14, 17, and the charging control circuit 22 are backup power supplies. A switching unit 23 is configured.

  In the joint encoder power supply apparatus of this embodiment, the backup circuit 11 is connected to the backup power supply circuit 10 and the output voltage of the diode 12 for preventing the backflow of current to the backup circuit 11 side is the PCI power supply. The converter 13 supplies the output voltage of the diode 9 to 5.2 V so that the output voltage of the diode 9 is lower than the output voltage of the diode 9 that prevents the backflow of current to the nickel hydride battery 6 side. And the converter 14 adjusts the output voltage of the diode 12 to 5.0 V. Therefore, while the PCI power supply circuit 8 supplies the main power from the nickel metal hydride battery 6 via the diode 9, the above voltage is maintained. Due to the difference, the diode 12 does not supply the backup power, and the system switch 18 is turned on. Automatically when supply circuit 8 of the PCI power such as by the FF no longer supplies the main power through the diode 9 from a nickel hydrogen battery 6, the diode 12 is adapted to supply backup power from a backup circuit 11.

  Here, the nickel cadmium battery 7 is connected to the backup circuit 11 and the output voltage 10.8 V of the diode 16 for preventing the backflow of current to the nickel cadmium battery 7 side is connected to the backup circuit 11 and the nickel metal hydride battery 6. And the converter 17 adjusts the output voltage of the diode 15 to 13.0 V so that the output voltage of the diode 15 is lower than the output voltage of the diode 15 that prevents the reverse flow of current to the nickel hydrogen battery 6 side. Is supplying backup power via the diode 15, the nickel cadmium battery 7 does not supply backup power via the diode 16 due to the above voltage difference, and the backup supplied by the nickel metal hydride battery 6 via the diode 15. Power supply voltage However, when the voltage of the backup power supply supplied by the nickel cadmium battery 7 via the diode 16 becomes lower, the nickel cadmium battery 7 automatically supplies the backup power supply to the backup circuit 11 via the diode 16.

  Therefore, according to the joint encoder power supply device of this embodiment, even when the nickel metal hydride battery 6 is used as the main power supply, the nickel metal hydride battery 6 and the nickel cadmium battery 7 do not have a switching control circuit when the main power supply is cut off. Double backup can be performed. Moreover, since the main power source and the backup power source are automatically switched and supplied from the nickel-metal hydride battery 6 for operation mounted on the humanoid robot, the backup power source can be supplied for a longer period of time than the case of only the backup from the nickel cadmium battery 7. It can be carried out.

  Furthermore, in the joint encoder power supply device of this embodiment, a commercial power source is connected to the backup circuit 11 and a backflow of current to the commercial power source side is prevented, and the output voltage of the diode 19 is that of the diode 15. Since the AC-DC converter 20 that adjusts the output voltage of the diode 19 so as to be higher than the output voltage of the diode 16 and the output voltage of the diode 16 is provided, the commercial power supply AC100V is supplied to the humanoid robot. When the power is cut off, the backup power is first supplied from the commercial power supply, so that triple backup can be performed without a switching control circuit.

  The joint encoder power supply device of this embodiment includes the charge control circuit 22 for charging the nickel cadmium battery 7 using the commercial power supply, and therefore the commercial power supply AC100V is supplied to the humanoid robot. Since the nickel cadmium battery 7 can be always charged using the commercial power supply during the operation, it is more reliable even when the main power supply is unintentionally disconnected and when the nickel metal hydride battery 6 is removed at the same time when the main power supply is turned off. Can be backed up.

  Although the present invention has been described based on the illustrated example, the present invention is not limited to the above example. For example, the walking robot is not limited to the humanoid robot, and the types of the main battery and the spare battery are also limited to the above. Absent. Then, only one backup converter may be provided depending on the voltage setting of the main power supply or the backup power supply.

  Thus, according to the joint encoder power supply device for a walking robot of the present invention, even when the battery is used as the main power supply, when the main power supply is cut off, the main battery and the spare battery can perform double backup without a switching control circuit. In addition, the main power supply and the backup power supply are automatically switched and supplied from the main battery for operation mounted on the walking robot, so it is possible to supply backup power for a longer period than when only backup from the spare battery is used. Can do.

It is a block diagram which shows one Example of the power supply apparatus for joint encoders of the walking robot of this invention. (A), (b) is the front view and side view which show the whole humanoid robot to which the power supply apparatus for joint encoders of the walking robot of the said Example is applied. It is a block diagram which shows an example of the power supply apparatus for joint encoders of the conventional robot.

Explanation of symbols

1 fuselage 1a fuselage upper half 1b fuselage lower half 2 legs 3 arms 4 heads 5 up / down counter 6 nickel metal hydride battery 7 nickel cadmium battery 8 PCI power supply circuit 9, 12, 15, 16, 19 diode 10 backup power supply Supply circuit 11 Backup circuit 13, 14, 17, 20 Converter 18 System switch 21 Temperature sensor 22 Charge control circuit 23 Backup power supply switching unit

Claims (3)

In a power supply device for supplying a main power source and a backup power source to a storage means for storing an output signal of an encoder for detecting a rotation position of a joint of a walking robot,
A main battery for supplying only the main power source and the backup power source, respectively mounted on the walking robot, and a reserve battery having an output voltage lower than the output voltage of the main battery but higher than the voltage of the backup power source ;
A first diode that connects the main battery to the main power supply circuit and prevents backflow of current to the main battery;
A second diode for connecting a backup circuit to the backup power supply circuit and preventing backflow of current to the backup circuit;
A backup converter for adjusting an input voltage of the second diode so that an output voltage of the second diode is lower than an output voltage of the first diode;
A third diode that connects the main battery to the backup circuit and prevents backflow of current to the main battery;
A fourth diode for connecting the backup battery to the backup circuit and preventing reverse current flow to the backup battery side;
A battery converter for adjusting an input voltage of the third diode so that an output voltage of the fourth diode is lower than an output voltage of the third diode ;
A power supply device for a joint encoder of a walking robot. A fifth diode for connecting a commercial power source to the backup circuit and preventing backflow of current to the commercial power source side;
A commercial power converter for adjusting the output voltage of the fifth diode to be higher than the output voltage of the third diode and the output voltage of the fourth diode;
The power supply apparatus for joint encoders of a walking robot according to claim 1, comprising:   The power supply device for the joint encoder of the walking robot according to claim 2, further comprising charging means for charging the spare battery using the commercial power source.

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