Magnetic liquid metal processing method, liquid gripper and manipulation method
A method for preparation of a magnetic liquid metal includes: 1) placing A parts by weight of a liquid metal in a container; 2) placing B parts by weight of a metal powder in the container; 3) adding an acidic solution into the container until the liquid metal and the metal powder are submerged; 4) stirring until the liquid metal and the metal powder are sufficiently mixed; and 5) adding water for cleaning the acidic solution, to obtain the magnetic liquid metal by removing the acidic solution. The viscosity and stiffness of the prepared magnetic liquid metal can quickly respond to the stimulus from an applied magnetic field, and a reversible change from liquid to semisolid or solid exists. With a change in magnetic field strengths, the Young's modulus can be regulated in a range from the level of kPa to the level of MPa.
1 . A microgripper, comprising a magnetic liquid metal, wherein the microgripper comprises a bowl-shaped claw, the magnetic liquid metal is disposed within the claw, an electrode is connected to the magnetic liquid metal, and the microgripper also comprises a magnet configured to apply a magnetic field to the magnetic liquid metal;
wherein at least one through hole for the electrode to pass is disposed on the claw.
2 . The microgripper according to claim 1 , wherein the claw is made of resin, an inner wall of the claw is coated with a copper powder by application of an adhesive.
3 . The microgripper according to claim 2 , wherein the adhesive is a pressure sensitive adhesive.
4 . The microgripper according to claim 1 , wherein:
a plurality of metal wires are disposed on an inner wall of the claw.
5 . The microgripper according to claim 4 , wherein:
the magnet is disposed on a top end of the base; and
the claw is disposed on a bottom end of the base.
6 . The microgripper according to claim 1 , further comprising:
a base for the claw;
wherein the electrode passes through the base and the though hole and is connected to the magnetic liquid metal.
7 . A gripping method using a magnetic liquid metal, wherein the gripping method comprises:
1) putting an object in an electrolyte;
2) adding the magnetic liquid metal dropwise;
3) applying direct current to the electrolyte via electrodes, wherein a positive electrode is connected to the magnetic liquid metal and a negative electrode is connected to the electrolyte, such that the magnetic liquid metal is diffused in the electrolyte and wraps up the object;
4) applying a magnetic field to the magnetic liquid metal through a magnet, such that the magnetic liquid metal enters into a solid-like state;
5) moving the magnetic liquid metal to drive movement of the object therein to a target position; and
6) Removing the magnetic field of the magnet and energizing the electrolyte via the electrodes, wherein the negative electrode is connected to the magnetic liquid metal and the positive electrode is connected to the electrolyte, such that the magnetic liquid metal is restored to a liquid state and concentrated on the electrode, so as to get away from the object.
8 . The gripping method according to claim 7 , wherein the electrolyte is a sodium hydroxide solution; the magnet is a permanent magnet or an electromagnet.
9 . The gripping method according to claim 7 , wherein the magnetic liquid metal is prepared by the following process:
1) placing A parts by weight of a liquid metal in a container;
2) placing B parts by weight of a metal powder in the container, the metal powder being a single non-magnetic ferromagnetic metal or a mixture of at least one non-magnetic ferromagnetic metal and other metals;
3) adding an acidic solution into the container until the liquid metal and the metal powder are submerged;
4) stirring until the liquid metal and the metal powder are sufficiently mixed; and
5) adding water for cleaning the acidic solution, and obtaining the magnetic liquid metal by removing the acidic solution.
10 . The gripping method according to claim 7 , wherein the gripping method is performed by using a microgripper,
the microgripper comprises a bowl-shaped claw, the magnetic liquid metal is added to the claw in step (2)
an electrode of the microgripper is connected to the positive electrode in step (3), and the object is wrapped in the magnetic liquid metal within the claw of the microgripper;
the microgripper also comprises the magnet configured to apply the magnetic field to the magnetic liquid metal in step (4);
the magnetic liquid metal is moved by moving the microgripper in step (5); and
the electrode of the microgripper is connected to the negative electrode in step (6).