cff-version: 1.2.0
abstract: "This data-set was collected as part of the experimental validation of a Jacobian-based stiffness analysis for parallel manipulators with two end-effectors and non-redundant legs. Measurements have been performed over the workspace of a passive planar 4-DoF mechanism with two end-effectors. The mechanism has four RPR legs, which are connected to the base, while in addition two RRR chains internally connect the two end-effectors and the terminal links of the three legs. The mechanism is described as 4-DoF, because rotation of both end-effectors is not considered. This rotation is free due to the collocation of joints at the end-effector, which means that no moments can be applied on the end-effectors by the mechanism.  Rotation was therefore not considered in the analysis. 

The dataset is stored as a tab-delimited ASCII file. The dataset consists of planar force measurements on both the first end-effector (EE1) and the second end-effector (EE2). As such, the resulting 4-dimensional measurement vectors contain the force components, f_{x,EE1}, f_{y,EE1}, f_{x,EE2} and f_{y,EE2}. 

The data has been separated in six subsets of measurements, where each subset is marked by a letter in the first column. Each subset consists of five arrays, where the first array describes the force measurement at a reference pose, followed by four arrays that describe the planar wrench measurements at a 5 mm displacement of the first end-effector (EE1) along the X-axis, a 5 mm displacement of the second end-effector (EE2) along X-axis, a 5 mm displacement of EE1 along the Y-axis, and a 5 mm displacement of EE2 along the Y-axis respectively. 

The pose of the mechanism was set manually, using a calliper, with estimated accuracies of 1/80 [rad] and 1/2000 [m] respectively. The pose of EE1 is defined by p_{x,EE1} and p_{y,EE1}, while that of EE2 is defined by p_{x,EE2} and p_{y,EE2}. Rotation of both end-effectors was held constant at zero degrees so that the measurement frame was aligned with the inertial frame. Wrench measurements were performed using an ATI mini40 sensor with SI-40-2 calibration, with maximum resolution of 1/4000 [Nm] and 1/100 [N] respectively.
Parent item:
Wrench Measurements on a Planar, Passive, 4-DoF Parallel Mechanism with Two End-Effectors and a Spatial, Passive, 2-DoF Parallel Mechanism with Two End-Effectors
Data collected as part of the experimental validation of a Jacobian analysis of a parallel mechanism with two end-effectors, as well as the experimental validation of a Jacobian-based stiffness analysis for parallel manipulators with two end-effectors."
authors:
  - family-names: Hoevenaars
    given-names: Antonius
    orcid: "https://orcid.org/0000-0002-4448-2289"
title: "Wrench Measurements on a Planar, Passive, 4-DoF Parallel Mechanism with Two End-Effectors"
keywords:
version: 1
identifiers:
  - type: doi
    value: 10.4121/uuid:d40eaac1-08aa-42ef-9c14-fae37d38e131
license: 4TU General Terms of Use
date-released: 2015-11-23