BOLCOF: Base Optimization for middle Layer Completion of
3D-printed Objects without Failure
Kenta Yamamoto

University of Tsukuba
kenta.yam@digitalnature.slis.
tsukuba.ac.jp

Ryota Kawamura

University of Tsukuba
kawamura@digitalnature.slis.
tsukuba.ac.jp

Riku Iwasaki

University of Tsukuba
riku@digitalnature.slis.tsukuba.ac.jp

Bektur Ryskeldiev

University of Tsukuba
bektour@digitalnature.slis.tsukuba.
ac.jp
(a)

Tatsuya Minagawa

University of Tsukuba
mina.tatsu@digitalnature.slis.
tsukuba.ac.jp

Yoichi Ochiai

University of Tsukuba
Pixie Dust Technologies, Inc.
wizard@slis.tsukuba.ac.jp

(b)

(d)

(c)

(e)

Figure 1: (a) 3D printer with BOLCOF-method installed. The depth sensor is attached to a ready-made 3D printer. (b), (d):Photographs of the result of printing on the object whose printing has been completed in the middle. The white filament partis the form printed earlier and the red filament part is the form printed afterwards. (c), (e): Models of objects that have been
printed halfway.

CCS CONCEPTS• Hardware → Printers;

KEYWORDS
3D printing , sensing , geometry
ACM Reference Format:
Kenta Yamamoto, Riku Iwasaki, Tatsuya Minagawa, Ryota Kawamura, Bektur Ryskeldiev, and Yoichi Ochiai. 2018. BOLCOF: Base Optimization formiddle Layer Completion of 3D-printed Objects without Failure. In Proceedings of SIGGRAPH ’18 Posters. ACM, New York, NY, USA, 2 pages.
https://doi.org/10.1145/3230744.3230768

1INTRODUCTION

3D printing failures can occur without completion of printing process due to shaking, errors in printer settings, and shape of thesupport material and 3D model. In such case it could be difficult
SIGGRAPH ’18 Posters, August 12-16, 2018, Vancouver, BC, Canada© 2018 Copyright held by the owner/author(s).
This is the author’s version of the work. It is posted here for your personal use. Notfor redistribution. The definitive Version of Record was published in Proceedings ofSIGGRAPH ’18 Posters, https://doi.org/10.1145/3230744.3230768.

to restart printing process from the last printed layer in conventional 3D printers, as the printing parts to which the nozzles aresupposed to be attached are lost. In order to restart printing fromthe middle layer, Wu et al.[Wu et al. 2017] proposed a method of
printing while rotating the base of a 3D printer. However, suchapproach required time for two objects to bond after segmentation,with limited availability of methods for adhesion between parts.
Wu et al.[Wu et al. 2016] have also proposed a method to print 3Dmodels at any angle through 5-axis rotation of the base of a 3D
printer, but the manufacturing cost of such approach was relatively
high. Therefore, we propose a system that prints 3D models on
existing object by utilizing an infrared depth camera. Our method
makes it possible to attach a 3D-printed object into a free-formed
object in the middle of printing by recognizing its shape with adepth camera.

2PIPELINE

As shown in Figure 2, in this study we investigate how an object,scanned on 3D printer’s table, can be reproduced with consideration of printing material, shape, and printer’s motor movement.
We created parts as seen in Figure 1(a) and incorporated them into

SIGGRAPH ’18 Posters, August 12-16, 2018, Vancouver, BC, Canada

RealSense SR300
Setup on Platform

Target Object3D Scan

STL

K. Yamamoto et. al.

Build Platform
Coordinate system
VirtualCoordinate system

Original 3D
modelCalibration

Boolean

3D Printing

Figure 2: We developed the process of 3D printing that restart to print from the middle of layer.
HICTOP printer1 . The depicted position in which the part was fixedallows to measure it at the same angle as the nozzle, and furthermore it allows extending the range of nozzle’s output. When the Z
axis is raised to the maximum level by a 3D printer, the distancefrom the table is approximately 25 cm. Also, if the shape acquired
by RealSense2 is tilted with respect to the actual table, an error
occurs when the nozzle of the 3D printer is moved in the X, Y, andZ axis directions, causing the printing to fail. To overcome that, we
installed a rectangular parallelepiped of the same scale as the actual
table in CINEMA4D3 , and calibrated by mapping the surface of thetable. The heat bed of HICTOP has a play on the base and the headpart by the spring. Therefore, even if the heat bed is pushed in, theoutput can be performed after the nozzle reaches the ideal heightfor printing.
In this research, errors occurred in the Z axis of the existing shapesurface scanned through RealSense. In order to adhere the filaments, it is necessary to slightly push the nozzle. Therefore, byusing a spring with a weaker repulsion force than the original part,
investigation was made so that the nozzle can be pushed in while
preventing destruction of the existing shape. Using a spring longer
than 30 mm will make the heat bed unstable. Therefore, a spring
has a spring coefficient of 0.3584[km/h], an outer diameter of 5 mm,a wire diameter of 0.8 mm, and a length of 30 mm was used.
The user fixes the object to be printed on the base of the original
3D printer. Move RealSense mounted on a 3D printer to a predetermined position, perform scanning, and convert it to STL format.
The scanned data is aligned with the zero coordinate of the nozzleof the 3D printer. After that, calibration is performed so that thecoordinates of the surface of the object can be accurately handledeven if RealSense is deviated. Then recognize the calibrated existing object as a new shape table and scaling with the output object.
Furthermore, the user adjusts the shape of the target shape and adjusts the position of the scanned existing object. After the decision,
the common part between the existing object and the target shapeis deleted, and only the part to be additionally printed remains.
In order to visualize intermediate processing and monitor errors
this time, visualization is performed using CINEMA4D after STL
conversion.

3

RESULT

We assumed the surface of the object where 3D-printed failed andgenerated fragments of cubes with sections of various angles as
1 https://www.hic3dprinter.com/
2 https://realsense.intel.com/

3 https://www.maxon.net/en/products/cinema-4d/

(a)

(b)

Figure 3: (a) A Stanford bunny model can be printed directlyon the surface of a non-flat bottle cap. (b) If a printing process is adopted in which the height of the nozzle changes
according to the shape of the object, printing on an object
with a large change in height becomes possible.
shown in Figure 1. In the figure, it was shown that although there
was a gap, it could be restored back to the final target object. It wasalso found that restoration is possible not only on flat slopes but
also on curved surfaces. Because a 3D printer can print directly on
existing objects, it can print Stanford bunny directly on a non-flat
surface like a cap (Figure 3 (a)).

4

DISCUSSION

In this study we have developed a method which allows continuation of object printing without adhesive, which we have successfully
tested with the fragments of a broken bowl on the 3D printer platform. Currently the main challenge for us is to solve the issue ofcollision of the nozzle with the fragment during the printing process, as our method is unable to detect the moment of collision
between the nozzle and the object (Figure 3 (b)). In the future weare hoping to avoid collision by outputting G-code that includes
vertical movement of the nozzle. Alternative approach would bereplacing the nozzle with a thinner option and adding a rotating
platform.

REFERENCES
Lifang Wu, Miao Yu, Yisong Gao, Dong-Ming Yan, and Ligang Liu. 2017. Multi-DOF
3D Printing with Visual Surveillance. In SIGGRAPH Asia 2017 Posters (SA ’17). ACM,New York, NY, USA, Article 6, 2 pages. DOI:http://dx.doi.org/10.1145/3145690.
3145728
Rundong Wu, Huaishu Peng, François Guimbretière, and Steve Marschner. 2016. Printing Arbitrary Meshes with a 5DOF Wireframe Printer. ACM Trans. Graph. 35, 4,Article 101 (July 2016), 9 pages. DOI:http://dx.doi.org/10.1145/2897824.2925966