System and method for controlling mobile platform through cooperation of two feet

Abstract

The invention discloses a system and method for controlling a mobile platform through cooperation of two feet. The system comprises a motion capture positioning point, an accelerator pedal, a positioner, an upper computer and the mobile platform. A robot operator wears a motion capture positioning point with the left foot and treads an accelerator pedal with the right foot, the positioner is placed around the operator, it is guaranteed that the motion capture positioning point is within the detection range of the positioner, motion capture data of the two feet is collected and input into an upper computer, and the motion capture data is calculated into a speed instruction and then transmitted to a mobile platform; an operator controls the robot moving platform to move in a left and right foot matching mode, control over the moving platform can be achieved through two legs, the mapping proportion can be adjusted in real time, and then fast moving and fine moving are both considered.

Description

Technical Field

[0001] The present invention belongs to the technical field of robots, and in particular relates to a system and method for controlling a mobile platform by using two feet in coordination. Background Art

[0002] With the development of technology, humanoid robots with humanoid arms and hands are expected to play a role in many fields such as home services, industrial production, military, aerospace, etc., and thus assist or replace humans in performing boring, dangerous, and complex tasks. In particular, they can replace humans in dangerous environments such as space exploration, deep-sea exploration, and disaster relief to complete complex tasks on the front line. Due to the current level of technology, it is still difficult for humanoid robots to achieve fully autonomous operation. Using human-in-the-loop remote control to plan the tasks and trajectories of humanoid robots is still the most feasible solution in the short term.

[0003] Based on the humanoid robot's upper limbs of arms and hands, the lower limbs may be in the form of legs, tracks, wheels and other mobile platforms depending on the terrain. In most cases, its movement mode can be regarded as a planar mobile rigid body with a maximum of 3 degrees of freedom.

[0004] Therefore, in order to control the movement of the humanoid robot mobile platform on the ground, the traditional remote control method usually uses a joystick control, mapping the angular displacement of the joystick in a certain direction to the speed command of one of the three degrees of freedom. However, since this method occupies both hands, it can still be used when only the mobile platform needs to be controlled, and the remote control of the humanoid robot's arms and hands also requires both hands for real-time control. Therefore, this method cannot achieve the linkage control of the mobile platform and the arms and hands, and has certain limitations.

[0005] To solve this problem, the control of the mobile platform is changed to two legs or two feet, so that the mobile platform and two arms and two hands can be controlled at the same time. In the existing technical route, there are mainly two types: universal treadmill and universal foot plate.

[0006] The universal treadmill can intuitively map the running direction of the human operator into the speed instruction of the robot mobile platform. The disadvantage is that during the mobile operation, people always need to stand, and people need to move on the treadmill for long periods of time, which consumes a lot of physical energy.

[0007] The universal pedal is a 3-DOF reset rocker that can be stepped on by foot. The deflection angle of the pedal can be mapped to the speed command of the mobile platform. The operator does not need to run and can be operated while sitting. The disadvantage is that when performing lateral translation and rotation compound movements, the pedaling posture is tiring, and it is difficult to adjust the mapping ratio in real time, making it difficult to balance fast movement and fine movement. Summary of the invention

[0008] In view of this, the present invention provides a system and method for controlling a mobile platform using both feet, which can realize the control of the mobile platform using both legs and can adjust the mapping ratio in real time, thereby taking into account both fast movement and fine movement.

[0009] The technical solution for implementing the present invention is as follows:

[0010] A system for controlling a mobile platform using both feet, including a motion capture positioning point, an accelerator pedal, a positioner, a host computer, and a mobile platform;

[0011] The robot operator wears a motion capture positioning point on his left foot and steps on the accelerator pedal with his right foot. The locator is placed around the operator to ensure that the motion capture positioning point is within its detection range. The motion capture data of both feet is collected and input into the host computer, which is then solved into speed instructions and passed to the mobile platform. The operator controls the movement of the robot mobile platform by coordinating his left and right feet.

[0012] A method for controlling a mobile platform using both feet, comprising the following steps:

[0013] Step 1: Use motion capture equipment to collect foot movements to calculate foot postures, and use the accelerator pedal as the algorithm starter and proportional mapping device;

[0014] Step 2: The foot movement data and the depth data of the accelerator pedal are transmitted to the host computer for motion calculation, which is then converted into speed instructions and transmitted to the robot mobile platform.

[0015] Furthermore, the operator wears a motion capture positioning point on his left foot and uses a locator to collect the spatial position of the motion capture positioning point, thereby knowing the position x, y, θ (x, y are plane position coordinates, and θ is the angle of rotation around the z-axis) of the left foot on the ground; the operator steps on the accelerator pedal with his right foot to control the depth k of the accelerator pedal; the position of the left foot on the ground and the depth of the accelerator pedal controlled by the right foot are transmitted to the host computer, which maps it into a speed command of the mobile platform, and finally sends the speed command to the mobile platform of the humanoid robot.

[0016] Furthermore, the mapping method is:

[0017] (1) The accelerator pedal depth response threshold is set to k0. When the accelerator pedal depth k≤k0, the mapping algorithm is invalid. When the accelerator pedal depth k>k0, the mapping algorithm takes effect and the left foot position at this time is recorded and defined as the initial position x0, y0, θ0.

[0018] (2) When controlling the robot to move, the left foot slides out in the direction of the desired platform movement, causing the left foot posture to deviate from the initial position. The current posture is recorded as x1, y1, θ1;

[0019] (3) Controlling the movement of the mobile platform requires three speed instructions, v x , vy ,ω z ; According to the formula:

[0020] v x =(k-k0)*(x1-x0)

[0021] v y =(k-k0)*(y1-y0)

[0022] ω z =(k-k0)*(θ1-θ0).

[0023] Furthermore, when the mobile platform needs to stop moving, just lift the accelerator pedal, then the mapping algorithm becomes invalid and the speed in each direction is reset to zero.

[0024] Beneficial effects:

[0025] Compared with the prior art, the present invention has the following advantages:

[0026] (1) The speed mapping ratio can be easily adjusted through the accelerator pedal, taking into account both fast and fine movement, and emergency stop can be achieved by releasing the pedal.

[0027] (2) The sliding direction of the foot is consistent with the speed direction of the platform, which is highly intuitive, can improve operating efficiency, and has low training costs.

[0028] (3) Based on the 3-DOF offset between the foot and the initial position as the basic speed instruction, the placement of the legs and feet can be unrestricted, and a natural and comfortable placement range can be found. Compared with existing technologies, this can effectively reduce fatigue. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a schematic diagram of a system for controlling a mobile platform using the cooperation of both feet according to the present invention.

[0030] Figure 2 Schematic diagram of the mapping algorithm of the present invention.

[0031] Among them, 1-motion capture positioning point, 2-accelerator pedal, 3-locator, 4-host computer, 5-mobile platform. DETAILED DESCRIPTION

[0032] The present invention is described in detail below with reference to the accompanying drawings and embodiments.

[0033] The present invention provides a system for controlling a mobile platform by using both feet. Figure 1 The control system consists of a motion capture positioning point 1, an accelerator pedal 2, a positioner 3, a host computer 4, and a mobile platform 5.

[0034] The robot operator wears a motion capture positioning point 1 on his left foot and steps on the accelerator pedal 2 with his right foot. The positioner 3 is placed around the operator to ensure that the positioning point 1 is within its detection range. The collected motion capture data is connected to the host computer 4, solved into speed instructions and then transmitted to the mobile platform 5; the operator controls the movement of the robot mobile platform by coordinating his left and right feet.

[0035] The specific technical scheme of the method of the present invention is:

[0036] The operator wears a motion capture positioning point on his left foot, and uses a positioner to collect the spatial position of the motion capture positioning point, and then knows the position x, y, θ of the left foot on the ground (x, y are the plane position coordinates, and θ is the angle of rotation around the z axis). The operator steps on the accelerator pedal with his right foot to control the accelerator pedal depth k. The position of the left foot on the ground and the accelerator pedal depth controlled by the right foot are transmitted to the host computer, which maps it into the speed command of the mobile platform, and finally sends the speed command to the mobile platform of the humanoid robot.

[0037] The specific mapping method is as follows Figure 2 As shown:

[0038] (1) The accelerator pedal depth response threshold is set to k0. When the accelerator pedal depth k≤k0, k=k0, and the mapping algorithm is invalid. When the accelerator pedal depth k>k0, the mapping algorithm takes effect. The left foot posture at this time is recorded and set as the initial posture x0, y0, θ0.

[0039] (2) When controlling the robot to move, the left foot slides in the direction of the desired platform movement, causing the left foot posture to deviate from the initial position. The current posture is recorded as x1, y1, θ1.

[0040] (3) Controlling the movement of the mobile platform requires three speed instructions, v x , v y ,ω z According to the formula:

[0041] v x =(k-k0)*(X1-X0)

[0042] v y =(k-k0)*(Y1-Y0)

[0043] ω z =(k-k0)*(θ1-θ0)

[0044] The three speed instructions are calculated and the response mode of the three speed instructions is determined according to the specific form of the robot mobile platform.

[0045] For example, omnidirectional mobile platforms such as Mecanum wheels and leg-footed platforms can y The response is the forward and backward movement speed, v xThe response is the left and right lateral speed, ω z The response is the steering speed, and the general movement is the synthesis of the three;

[0046] For example, the Ekman steering platform can y The response is the forward and backward movement speed, for v x No response, z The response is the steering mechanism angle.

[0047] According to the above mapping method, the operator can first lightly step on the accelerator pedal to exceed the threshold, and then slide the left foot to control the movement of the robot. Under the premise that the accelerator pedal exceeds the threshold, the position of the left foot remains unchanged after sliding. The deeper the accelerator pedal is pressed, the faster the platform moves in all directions; when the depth of the accelerator pedal remains unchanged, the farther the left foot slides relative to the initial position, the faster the platform speed. In this way, the mobile platform can be controlled by cooperating with the left and right feet.

[0048] When the mobile platform needs to stop moving, just lift the accelerator pedal, the mapping algorithm will be invalid, the speed in all directions will be reset, and the left foot can move freely. The next time you step on the accelerator pedal, the new initial position of the left foot will be recorded, and there is no need to find the previous initial position.

[0049] In summary, the above are only preferred embodiments of the present invention and are not intended to limit the protection scope of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A system for controlling a mobile platform using both feet, characterized in that: Including motion capture positioning points, accelerator pedal, locator, host computer, and mobile platform; The robot operator wears a motion capture positioning point on his left foot and steps on the accelerator pedal with his right foot. The locator is placed around the operator to ensure that the motion capture positioning point is within its detection range. The motion capture data of both feet is collected and input into the host computer, which is then solved into speed instructions and passed to the mobile platform. The operator controls the movement of the robot mobile platform by coordinating his left and right feet.

2. A method for controlling a mobile platform applied to the system of claim 1, characterized in that: The following steps are involved: Step 1: Use motion capture equipment to collect foot movements to calculate foot postures, and use the accelerator pedal as the algorithm starter and proportional mapping device; Step 2: The foot movement data and the depth data of the accelerator pedal are transmitted to the host computer for motion calculation, which is then converted into speed instructions and transmitted to the robot mobile platform.

3. The method according to claim 2, characterized in that The operator wears a motion capture positioning point on his left foot and uses a locator to collect the spatial position of the motion capture positioning point, thereby knowing the position x, y, θ of the left foot on the ground; the operator steps on the accelerator pedal with his right foot to control the depth k of the accelerator pedal; the position of the left foot on the ground and the depth of the accelerator pedal controlled by the right foot are transmitted to the host computer, which maps it into a speed command for the mobile platform, and finally sends the speed command to the mobile platform of the humanoid robot.

4. The method according to claim 2 or 3, characterized in that The mapping method is: (1) The accelerator pedal depth response threshold is set to k0. When the accelerator pedal depth k≤k0, the mapping algorithm is invalid. When the accelerator pedal depth k>k0, the mapping algorithm takes effect and the left foot position at this time is recorded and defined as the initial position x0, y0, θ0. (2) When controlling the robot to move, the left foot slides out in the direction of the desired platform movement, causing the left foot posture to deviate from the initial position. The current posture is recorded as x1, y1, θ1; (3) Controlling the movement of the mobile platform requires three speed instructions, v x , v y ,ω z ; According to the formula: v x =(k-k0)*(x1-x0) v y =(k-k0)*(y1-y0) oh z =(k-k0)*(θ1-θ0).

5. The method according to claim 2 or 3, characterized in that: When the mobile platform needs to stop moving, just lift the accelerator pedal. At this time, the mapping algorithm becomes invalid and the speed in each direction is reset to zero.

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