JP2009241246A - Semi-automatic travelling method for irregular ground movable body - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem of a difficulty in remote control although traveling performance is enhanced, in a conventional traveling method employed in a movable body which not only travels by a main propulsion generating section but also travels by using a movable arm to enhance the traveling performance. <P>SOLUTION: The irregular ground movable body has the main propulsion generating section, an movable arm, and a distance measuring device. The movable body is semi-automatically moved by moving the movable arm according to the terrain by using the distance measuring device and further with taking stability against falling into consideration. Thus, an operator can autonomously create a safety movement of the irregular ground moving mechanism corresponding to the irregular ground in the direction only by giving an instruction of the movement direction of the movable body. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to semi-autonomous traveling of a rough terrain moving body.

  Conventionally, there has been a moving body that moves on rough terrain, which has a movable arm mounted thereon in order to enhance its rough terrain traveling ability. However, while driving performance is improved, there is a problem that remote control of the moving body becomes very difficult.

  In order to solve the above-mentioned problem, a method for causing the rough terrain moving body to perform an operation plan in advance has been reported (for example, see Non-Patent Document 1).

In order to solve the above problem, research on semi-autonomous rough terrain traveling in which movement is determined from contact between the movable arm and the ground has been reported (for example, see Non-Patent Document 2). Non-Patent Document 3 discloses a normalized energy stability margin in the semi-autonomous traveling method for a rough terrain moving body.
Yusuke Takai, Satoshi Fujimura, Masayuki Okugawa, Shuji Hashimoto, “Autonomous stepping control of rescue robot with sub-crawler”, Proceedings of Robotics and Mechatronics Lecture '07, pages 2P1-J04 (1)-(2) , 2007. Kazunori Ohno, Shouich Morimura, Satoshi Tadokoro al., "Eiji Koyanagi, and Tomoaki Yoshida." Semi-autonomous control system of rescue crawlerrobot having flippers for getting over unknownsteps ", Proceedings of the 2007 IEEE / RSJ International Conference on Intelligent Robots and Systems, pages 3012-3018, 2007. Written by Shigeo Hirose, Hideyuki Tsukagoshi, and Yoneda. Static stability evaluation criteria for walking machines on rough terrain. Journal of the Robotics Society of Japan, 16 (8): 48-54, 1998.

  However, the above-described conventional method for causing the rough terrain mobile body to perform an operation plan in advance has a problem that it may not be able to flexibly cope with a change in the situation.

  The present invention has been made in view of such a problem, and provides a method of acquiring terrain information in a non-contact manner using a distance measuring device and realizing rough terrain operation by simple rules. Objective.

    According to the semi-autonomous traveling method for a rough terrain vehicle of the present invention, the terrain information is acquired in a non-contact manner by the distance measuring device, and the line segment connecting the movement center of the movable arm and the distance measurement point is within the movement range of the movable arm. The angle control of the movable arm is performed using the angle at which the movable arm contacts the distance measuring point that makes the maximum angle with the ground as the target angle.

  That is, the semi-autonomous traveling method of the present invention is a rough terrain moving body having a main propulsive force generating unit, a moving body main body, a movable arm, and a distance measuring device, and the main propulsive force generating unit is in contact with a traveling surface. The mobile body has a main propulsive force generating unit, the movable arm has the main propulsive force generating unit, and the distance measuring device has The angle at which the movable arm comes into contact with the distance measuring point that is mounted on the mobile body and maximizes the angle formed by the line connecting the movement center of the movable arm and the distance measuring point with the ground within the range of movement of the movable arm. The angle of the movable arm is controlled by using as a target angle.

  According to the semi-autonomous traveling method for the rough terrain moving body of the present invention, by taking into account the normalized energy stability margin proposed in Non-Patent Document 3 below, the stability of the moving body is also taken into consideration. Travel can be realized.

Hereinafter, the best mode for carrying out the present invention will be described.
First, the best mode for carrying out the (first) invention according to the semi-autonomous traveling method of the rough terrain moving body will be described.

FIG. 1 is a side view showing the rough terrain traveling operation of the rough terrain moving body according to the semi-autonomous traveling method of the rough terrain moving body of the present invention.
In FIG. 1, the rough terrain moving body includes a main propulsive force generating unit 1, a moving body main body 2, a movable arm 3, and a distance measuring device 4.

The main propulsion generator 1 will be described. The main propulsive force generating device generates propulsive force on the movable body main body by contact with the traveling surface. For example, there are wheels, an endless track mechanism, a leg mechanism, and the like, but it is not limited thereto. The movable body 2 and the movable arm 3 can be mounted.

The mobile body 2 will be described. The mobile body is a main body of the rough terrain mobile body, and its structure includes, for example, a light metal box type structure, but the material and the structure are not limited thereto.

The movable arm 3 will be described. The movable body 3 has a structure on the arm that operates relative to the movable body main body. As an example, the structure includes, for example, a light metal box type structure, but the material and the structure are not limited thereto. Further, the movement includes a rotational movement with respect to the moving body, but is not limited to this, and a combination of translational movements is also possible.

The distance measuring device 4 will be described. The distance measuring device 4 is installed with respect to the mobile body 2 so that the scanning plane is perpendicular to the ground. Measure the distance from the installation position to the obstacle ahead. Examples include an optical type such as a laser, but are not limited thereto.

ここで、（１）式は、移動体本体が接地する場合、（２）式は、後可動腕３が接地する場合である。なお、各パラメータは、図２内で定義されるものとする。仮に（１）式において、段差踏破が不可能となっても、後可動腕３を制御することで（２）式に移行することが可能となるため、段差踏破の議論は、（２）式のみに注目すればよい。（２）式の第３項を最大とするのは、θｂ−θｒ＝９０［ｄｅｇ］となるときであり、これは、後可動腕３が地面と垂直となる場合である。このθｂ＝θｍａｘとなるときが、ｈを最大とする条件であるため、θｍａｘが定まると、不整地移動体の踏破可能な段差の高さが計算可能となる。FIG. 2 is a geometric side view at the time of stepping over a rough terrain moving body according to the semi-autonomous traveling method of the rough terrain moving body of the present invention. Next, conditions for the rough terrain moving body to get over the step will be described. The condition is that the bottom height h of the center of gravity of the moving body on rough terrain (the distance between the bottom surface of the moving body and the ground on the straight line extending vertically downward from the position of the center of gravity, see FIG. 2) is to be overcome. For the step height H, h> H is satisfied. When this condition is satisfied, the center of gravity can exceed the contact point of the main propulsive force generating device 1 and the step, so that a clockwise moment is generated at the contact point and the step can be climbed. This h has two cases: geometrically when the movable body is grounded (upper stage in FIG. 2) and when the rear movable arm 3 is grounded (lower stage in FIG. 2).

Here, equation (1) is when the mobile body is grounded, and equation (2) is when the rear movable arm 3 is grounded. Each parameter is defined in FIG. Even if it is impossible to step through the step in the formula (1), it is possible to shift to the formula (2) by controlling the rear movable arm 3. You only need to pay attention to it. The maximum of the third term of the expression (2) is when θb−θr = 90 [deg], and this is a case where the rear movable arm 3 is perpendicular to the ground. The time when θb = θmax is a condition for maximizing h. Therefore, when θmax is determined, it is possible to calculate the height of a step that can be traversed by the rough terrain moving body.

FIG. 3 is a diagram showing an example of a normalized energy stability margin related to the semi-autonomous traveling method of the rough terrain vehicle of the present invention. Since the rough terrain moving body can control the angle of the front and rear movable arms 3, the normalized energy stability margin can be calculated by two variables of the angle θr of the rear movable arm 3 and the pitch angle θb of the main body. FIG. 3 is a graph showing the calculation results. The vertical axis represents the pitch angle θb of the main body, the horizontal axis represents the angle θr of the rear movable arm 3, and each color represents the normalized energy stability margin. The closer to yellow, the greater the stability margin. Since the calculation formula of h is different between the case where the rear movable arm 3 does not touch the ground and the case where the rear movable arm 3 touches the ground (see Formula (4) and Formula (5)), there is a discontinuous surface in the normalized energy stability margin. Arise. In this example, since the upper limit angle of the pitch angle of the mobile body 2 is set to θmax = 30 [deg], the lower the axis on the axis where θb = 30 [deg] (that is, the rear movable arm 3 is vertical). The closer to, the smaller the normalized energy stability margin. For example, considering that a 30% margin is considered with respect to the normalized energy stability margin on flat ground, the normalized energy stability margin is 0.15 [m]. It is desirable to suppress θr to about −20 [deg].
From the above, according to the best mode for carrying out the present invention, since the mobile body travels while grasping the terrain at each time, the rough terrain mobile body can travel semi-autonomously.

  The present invention is not limited to the best mode for carrying out the above-described invention, and various other configurations can be adopted without departing from the gist of the present invention.

It is a side view which shows the rough terrain traveling operation | movement of the rough terrain moving body in connection with the semi-autonomous traveling method of a rough terrain moving body. It is a geometric side view at the time of stepping over the uneven ground moving body related to the semi-autonomous traveling method of the uneven ground moving body. It is a figure which shows an example of the normalization energy stability margin in connection with the semi-autonomous traveling method of a rough terrain moving body.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Main propulsion generating part, 2 ... Mobile body, 3 ... Movable arm, 4 ... Optical distance measuring device, 5 ... Running surface, 6 ... Distance measuring point, 7 ... Step

Claims (2)

Semi-autonomous traveling method of rough terrain moving body having the following main propulsive force generating part, moving body main body, movable arm, and distance measuring device (a) Main propulsion that gives the moving body main body a propulsive force by contacting the traveling surface (B) A movable body equipped with the main propulsive force generating section (c) A movable arm equipped with the main propulsive force generating section (d) A distance measuring device mounted on the movable body main body The angle control of the movable arm is performed by setting the angle at which the movable arm contacts the distance measuring point that makes the maximum angle formed by the line segment connecting the movement center of the movable arm and the distance measuring point within the movement range to the ground as the target angle. Semi-autonomous driving method   The semi-autonomous traveling method according to claim 1, wherein the stability of the falling of the moving body is taken into consideration.

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