In Joint Limits

SUMMARY

In Joint Limits checks whether a candidate joint configuration is strictly inside the robot's configured per-joint lower and upper bounds. Use it as a guard before sending a joint target to the controller or before running motion planning.

SUPPORTED ROBOTS

Available on all supported manipulators.

UNITS

Input joint configuration q in degrees. Returns a boolean.

The Skill

ok = robot.in_joint_limits(q=q, verbose=False)

The Code

Example 1: Guard a Joint Target

Validate a candidate joint configuration before commanding the controller.

import numpy as np
from loguru import logger
from telekinesis.synapse.robots.manipulators import universal_robots

robot_ip = "192.168.1.2"  # replace with your robot's IP

robot = universal_robots.UniversalRobotsUR10E()
robot.connect(ip=robot_ip)

q_target = np.array([0.0, -90.0, 90.0, -90.0, -90.0, 0.0])

if robot.in_joint_limits(q_target):
    robot.set_joint_positions(q=q_target.tolist())
    logger.success("Joint target accepted and commanded.")
else:
    logger.error("Joint target is outside the configured limits - aborting.")

robot.disconnect()

Example 2: Validate an IK Solution Verbosely

Run IK and log details for any joint that violates a limit.

import numpy as np
from loguru import logger
from telekinesis.synapse.robots.manipulators import universal_robots

robot = universal_robots.UniversalRobotsUR10E()

target_pose = [0.4, 0.0, 0.3, 180.0, 0.0, 0.0]
q = robot.inverse_kinematics(target_pose=target_pose)

# Verbose mode logs which joint(s) are out of bounds
if not robot.in_joint_limits(np.asarray(q), verbose=True):
    logger.warning("IK solution violates joint limits - rejecting.")
else:
    logger.success(f"IK solution is within limits: {q}")

The Explanation of the Code

in_joint_limits reads the per-joint lower and upper bounds from robot.joint_limits and returns True only when every value in q is strictly between its bounds (lower < q < upper). Values exactly at the lower or upper bound are reported as out-of-limit, to avoid commanding the controller right at the edge of its motion envelope.

The input vector must be a 1D NumPy array in degrees whose length matches the number of joints on the robot. A ValueError is raised otherwise.

When verbose=True, the method also logs a warning per joint that violates its bounds, with the joint name, index, and the lower/upper bound. This is useful when diagnosing why an IK solution or planned waypoint is being rejected.

How to Tune the Parameters

Parameter	Type	Default	Description
q	np.ndarray	-	1D joint configuration in degrees. Length must match the number of joints on the robot.
verbose	bool	False	If True, log a warning for each joint value that violates its limit.

Return Value

Type	Description
bool	True if every joint value is strictly inside its configured [lower, upper] bounds, False otherwise.

Where to Use the Skill

• Pre-flight validation - Reject joint targets that would violate the configured limits before sending them to the controller
• IK post-processing - Filter IK solutions to keep only configurations inside the joint envelope
• Motion planning - Validate sampled or interpolated waypoints during planning
• Diagnostics - Use verbose=True to surface which joint is the offender when a target is rejected

When Not to Use the Skill

Do not use In Joint Limits when:

• You need workspace-level safety checks - for Cartesian-space safety bounds, use Is Pose Within Safety Limits.
• You need controller-side safety status - use Is Joints Within Safety Limits to query the controller's live safety state instead of the URDF limits.