Robot Load Compensation via Preloaded Elastic Body
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Robot apparatuses with movable portions, such as legs or arms, face continuous power consumption even when stationary due to deadweight loads, leading to inefficiency and increased energy usage.
Innovation Solution
Incorporating a load compensation mechanism using an elastic body with an initial displacement setting section that calculates and applies an initial displacement amount based on the weight of luggage and the robot's body weight, allowing the elastic body to generate a restoring force and reduce the load on joint actuators, thereby minimizing power consumption.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If an actuator continuously operates to maintain a stationary posture of the movable portion, then the desired position or posture is maintained, but power consumption increases
Solution Approach 1:
The patent applies counterweight principle by using a spring mechanism that generates elastic force to compensate for the gravitational load of the movable portion. The spring is pre-loaded to create an upward force that balances the downward weight, allowing the actuator to remain stationary rather than continuously operating, thus reducing power consumption while maintaining posture stability
Solution Approach 2:
The patent implements preliminary action by pre-compressing or pre-extending the spring during the initialization phase to store elastic potential energy. This preliminary displacement of the spring creates a restoring force that automatically compensates for the deadweight load before the actuator needs to operate, enabling passive support of the movable portion's weight
2Device complexity
If a fixed spring constant is used for deadweight compensation, then the structure is simple, but the compensation is ineffective under varying loads
Solution Approach 1:
The patent applies dynamics principle by making the spring constant variable rather than fixed. The system dynamically adjusts the spring constant based on the detected load conditions - using a first spring constant when the movable portion is stationary and a second spring constant when moving. This dynamic adaptation allows the compensation mechanism to effectively handle varying loads while maintaining reasonable structural complexity
Solution Approach 2:
The patent implements parameter changes by modifying the spring constant parameter according to operational conditions. The control unit detects whether the movable portion is in motion or stationary and selects appropriate spring constant values from multiple available springs or adjustable mechanisms, thereby adapting the elastic properties to match the current load and operational state for optimal compensation performance
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution enables the robot apparatus to maintain a desired posture with reduced power consumption, improving energy efficiency and extending battery life by dynamically adjusting the load compensation based on varying loads and positions.
Implementation Method 1
a load compensation section utilizing an elastic body to compensate for a load acting on the movable portion
Implementation Method 2
an initial displacement amount setting section applying, to the elastic body, an initial displacement amount corresponding to a desired position or posture of the movable portion
Data Source
AI summary
Provided is a robot apparatus that includes a load compensation function dealing with a variation in load, where the robot apparatus includes one or more movable portions, a load compensation section utilizing an elastic body to compensate for a load acting on the movable portion, and an initial displacement amount setting section applying, to the elastic body, an initial displacement amount corresponding to a desired position or posture of the movable portion. The initial displacement setting section includes an actuator displacing the elastic body by an initial displacement amount and locks the actuator with the elastic body remaining displaced by the initial displacement amount. The movable portion is a leg including a joint portion having a degree of rotational freedom around a pitch axis, and the initial displacement amount setting section sets the initial displacement amount on the basis of a toe force of the leg.