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Olimex LPC-H2148 Microcontroller Board Signals and instructions between the fab at home software and the hardware are interchanged with the help of the microcontroller board – Olimex LPC-H2148. This microcontroller is allocated with a large random access memory which enables for motion commands to be buffered. There is a USB connector on one of the sides of the microcontroller which can be used to connect direct with a computer for the transfer of signals and information. To program this board a provision of connecting with a Jtag adaptor is also given. JTAG adaptor cable, Programming the microcontroller and Firmware A JTAG adaptor cable is mainly used to code software onto a LPC-H2148 microcontroller which works within a firmware development environment. The JTAG adapter is currently not a part of the standard kit set of the fab at home machine model 1. For programming the microcontroller, software called Crossworks is required which involves connecting it with the computer with the help of a JTAG connector. At the moment, Rowley crossworks is known to be compatible with only two JTAG adaptors; a) Parallel port to ARM JTAG adapter and b) USB to ARM JTAG adapter from Rowley. As the available options are not the best options available it was chosen to make one ourselves. To program the microcontroller, the Rowley Crosswork for ARM chip support, Fab at home firmware drivers were downloaded and installed on the computer. To begin programming the microcontroller is first connected with the computer via the JTAG adapter. Once connection is established, Crossworks software is fired up. Now the Fab at home firmware and the workaround dummy project are opened from the “file > <strong>Open</strong> solution” option on Crossworks. A few other steps are followed as per the fab at home manual procedures and the firmware is flashed onto the microcontroller. The 68
microcontroller is now disconnected with the JTAG adapter and ready for working with the Fab@home machine. The software which runs on the LPC2148 microcontroller is essentially called the firmware and is written in C language using software called Rowley Crossworks for ARM. The manufacturer of the microcontroller preloads a simple demo firmware which needs to be replaced with our Fab at home firmware. The main channel of communication between the Fab@home machine and the computer are through the firmware. It is used in receiving, transmitting information from the software which is then forwarded on to the Fab@home machine. This information is then used by the Fab@home machine to achieve the co-ordinates and positions as commanded by the user. Winford Engineering DB-25 Breakout Board The main function of the Winford Engineering Breakout board is to ease the communications between microcontroller and the stepper motor diver board. On any signal, the Winford Engineering DB-25 breakout board allows a maximum of 2.25A and two hundred volt maximum between any two signals. The DB-25 Breakout board is used to connect the tow ribbon cables (which were prepared earlier) with the microcontroller and it also connects the DB-25 to IDC 26 Ribbon Cable with the stepper motor driver board. Assembling the Electronics to chassis The electronics mentioned above – Xylotex XS 3525/8S-4 Stepper motor driver board, Olimex LPC H2148 Microcontroller board, Winford Engineering DB-25 Breakout Board, ELMAC Power supply, AC Power cord, limit switches are connected all together with a help of a detailed schematic diagram given at Fab@home‟s wiki database. The boards are first mounted on to the chassis and using the available wires and the wiring diagram, the assembling is carried out. Once all the electronics are assembled as per the schedule it would look as shown in Fig. 3.3. 69
Page 1 and 2:
An Investigation into curved layer
Page 3 and 4:
Contents Abstract..................
Page 5 and 6:
3.5.2 Fabepoxy.....................
Page 7 and 8:
methodology to print simple curved
Page 9 and 10:
List of Figures 1.1 The Rapid proto
Page 11 and 12:
4.3 Parts being tested with Hounsfi
Page 13 and 14:
List of Abbreviations 3D: Three dim
Page 15 and 16:
Fig 1.1 The Rapid prototyping Cycle
Page 17 and 18: 1.1.1 Stereolithography Stereolitho
Page 19 and 20: The object to be made is first mode
Page 21 and 22: 1.1.5 Laser Engineered Net Shaping
Page 23 and 24: 1.2 Fused Deposition Modeling A det
Page 25 and 26: Fig 1.8 Deposition Head Different t
Page 27 and 28: 900mc is capable of producing parts
Page 29 and 30: noted that the parts built in this
Page 31 and 32: structure. Honeycomb scaffold archi
Page 33 and 34: optimal direction to build a part t
Page 35 and 36: processing treatment was analyzed w
Page 37 and 38: The actual influence of the curved
Page 39 and 40: Separating the Main part with its s
Page 41 and 42: limited to simple models. It could
Page 43 and 44: Fig 2.2 Faces, Edges and Vertices o
Page 45 and 46: 2.1.5 Constructive Solid Geometry C
Page 47 and 48: A STL file is a triangular represen
Page 49 and 50: Fig 2.8 A sample Binary STL File Sl
Page 51 and 52: Different processes may either vary
Page 53 and 54: At the very outset of generating th
Page 55 and 56: and correction of each point to sat
Page 57 and 58: apid prototyping machine are remove
Page 59 and 60: Fig 2.13 Main Part Fig 2.14 Support
Page 61 and 62: As this text file is to be used wit
Page 63 and 64: mounted to the axes carriage. Timin
Page 65 and 66: Fig 3.1 The deposition head At the
Page 67: 3.2.3 Assembling Electronics and ca
Page 71 and 72: The relationship between test point
Page 73 and 74: on the mechanical properties and po
Page 75 and 76: 3.5.1 Silicone with other materials
Page 77 and 78: Fab@home machine. Since our require
Page 79 and 80: are printed using the two suitable
Page 81 and 82: The support structure‟s dimension
Page 83 and 84: machine Fig 3.13 Flat and curved la
Page 85 and 86: 4.1 Experimental conditions Chapter
Page 87 and 88: have many factors from contention a
Page 89 and 90: 4.3 Taguchi methods There are two t
Page 91 and 92: Such steps usually identify the nee
Page 93 and 94: Nominal is best Larger is better S
Page 95 and 96: Control of material flow - The lead
Page 97 and 98: Fig 4.3 Parts being tested with Hou
Page 99 and 100: values in all cases are almost doub
Page 101 and 102: level. The other parameters were in
Page 103 and 104: The finite element method has had a
Page 105 and 106: performance of finished FDM parts [
Page 107 and 108: ehaviour with failure occurring at
Page 109 and 110: Fig. 2 (a) is the thin curved part
Page 111 and 112: Table 5.1 Property data: Fabepoxy M
Page 113 and 114: optimum number. The final finite el
Page 115 and 116: Fig. 5.11 Load and boundary conditi
Page 117 and 118: overall deflection pattern of two s
Page 119 and 120:
Fig. 5.13 Variation of compressive
Page 121 and 122:
Fig. 5.15 shows the overall deforma
Page 123 and 124:
The effectiveness of the deposition
Page 125 and 126:
[11] M. Greul, T. Pintat, M. Greuli
Page 127 and 128:
[32] Philip J. Ross, 1988, “Taguc
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