ikin_norm() | V3-manual

Definition

ikin_norm(pos, sol_space, ref, ref_pos_opt)

Features

This function returns the joint position corresponding to posx.sol, which is equivalent to the robot pose in the operating space, among 8 joint shapes. Joint position is returned according to closest joint position depend on option(ref_pos_opt). Through status of return value, you can check whether current robot pose is in wrist singularity or out of operating region. When DR_SOL_AUTO(255) is entered into posx.sol, it moves to robot configuration that is the closest to the current configuration, (the smallest L2 norm in the joint space of axes 2-5) among the reachable joint combination types.

Note

After SW version V2.9, It is possible to correct robot DH parameters for improving accuracy. Robots after SW version V2.10.1 are released with calibrated DH parameters for improving accuracy.
This function returns inverse kinematics solution related to each robot model's well known nominal DH parameters before calibrated DH parameters.
Refer to ikin() command to find the inverse kinematics solution related to calibrated DH parameters.

Parameters

Parameter Name	Data Type	Default Value	Description
pos	posx	-	posx or position list
pos	list (float[6])	-	posx or position list
sol_space	int	-	solution space None: Not available for v3.x DRL Command (Recommend using posx.sol) 0~7: Available for 2.x & 3.x DRL Command DR_SOL_AUTO(255): Available for 2.x & 3.x DRL Command
ref	int	DR_BASE	reference coordinate DR_BASE : base coordinate DR_WORLD : world coordinate
ref_pos_opt	int	0	Determine closest joint position depend on option among multi turn solutions 0 : posj(0,0,0,0,0,0) is reference 1 : current joint position is reference

Solution Space w.r.t. Robot Configuration

Solution space	Binary	Shoulder	Elbow	Wrist
0	000	Lefty	Below	No Flip
1	001	Lefty	Below	Flip
2	010	Lefty	Above	No Flip
3	011	Lefty	Above	Flip
4	100	Righty	Below	No Flip
5	101	Righty	Below	Flip
6	110	Righty	Above	No Flip
7	111	Righty	Above	Flip
255	Auto Calculation (the smallest L2 norm in the joint space of axes 2-5)

Return

Value	Description
posj	Joint space point
status	0 : Return joint position 1 : Out of workspace 2 : In wrist singularity region

Exception

Exception	Description
DR_Error (DR_ERROR_TYPE)	Parameter data type error occurred
DR_Error (DR_ERROR_VALUE)	Parameter value is invalid
DR_Error (DR_ERROR_RUNTIME)	C extension module error occurred
DR_Error (DR_ERROR_STOP)	Program terminated forcefully

Example

Python

## 2.x compatible code
x1 = posx(370.9, 719.7, 651.5, 90, -180, 0)
q1, status = ikin_norm(x1, 2, DR_BASE, ref_pos_opt=0) # Joint angle q1 where the coordinate of the robot edge is x1 (second of 8 cases), reference joint position : posj(0,0,0,0,0,0)
# q1=posj(60.3, 81.0, -60.4, -0.0, 159.4, -29.7) (M1013, tcp=(0,0,0))
movej(q1,v=10,a=20)

## 3.2~ code
x1 = posx(370.9, 719.7, 651.5, 90, -180, 0, sol=2)
q1, status = ikin_norm(x1, ref=DR_BASE, ref_pos_opt=0) # Joint angle q1 where the coordinate of the robot edge is x1 (second of 8 cases), reference joint position : posj(0,0,0,0,0,0)
# q1=posj(60.3, 81.0, -60.4, -0.0, 159.4, -29.7) (M1013, tcp=(0,0,0))
movej(q1,v=10,a=20)