Update Content - 2020-10-20

This commit is contained in:
Thomas Dehaeze 2020-10-20 16:00:25 +02:00
parent 2ba3bf426e
commit a504e2aa91
7 changed files with 81 additions and 11 deletions

33
content/zettels/cables.md Normal file
View File

@ -0,0 +1,33 @@
+++
title = "Cables"
author = ["Thomas Dehaeze"]
draft = false
+++
Backlinks:
- [Connectors]({{< relref "connectors" >}})
Tags
: [Connectors]({{< relref "connectors" >}})
## Typical Cables {#typical-cables}
- Coaxial cables
- Twisted cables
- Twisted shielded cables
## Manufacturers {#manufacturers}
| Manufacturers | Links | Country |
|---------------|---------------------------------|-------------|
| LEMO | [link](https://www.lemo.com/en) | Switzerland |
## Software {#software}
- [WireViz](https://github.com/formatc1702/WireViz) is a nice software to easily document cables and wiring harnesses
<./biblio/references.bib>

View File

@ -4,6 +4,10 @@ author = ["Thomas Dehaeze"]
draft = false
+++
Backlinks:
- [Signal Conditioner]({{< relref "signal_conditioner" >}})
Tags
: [Electronics]({{< relref "electronics" >}})
@ -15,6 +19,24 @@ A charge amplifier outputs a voltage proportional to the charge generated by a s
This can be typically used to interface with piezoelectric sensors.
## Basic Circuit {#basic-circuit}
Two basic circuits of charge amplifiers are shown in Figure [1](#org9ffcf40) (taken from ([Fleming 2010](#orgaceef58))) and Figure [2](#org37bd87f) (taken from ([Schmidt, Schitter, and Rankers 2014](#org683b96e)))
<a id="org9ffcf40"></a>
{{< figure src="/ox-hugo/charge_amplifier_circuit.png" caption="Figure 1: Electrical model of a piezoelectric force sensor is shown in gray. The op-amp charge amplifier is shown on the right. The output voltage \\(V\_s\\) equal to \\(-q/C\_s\\)" >}}
<a id="org37bd87f"></a>
{{< figure src="/ox-hugo/charge_amplifier_circuit_bis.png" caption="Figure 2: A piezoelectric accelerometer with a charge amplifier as signal conditioning element" >}}
The input impedance of the charge amplifier is very small (unlike when using a voltage amplifier).
The gain of the charge amplified (Figure [1](#org9ffcf40)) is equal to:
\\[ \frac{V\_s}{q} = \frac{-1}{C\_s} \\]
## Manufacturers {#manufacturers}
| Manufacturers | Links | Country |
@ -28,4 +50,9 @@ This can be typically used to interface with piezoelectric sensors.
| Sinocera | [link](http://www.china-yec.net/instruments/signal-conditioner/multi-channels-charge-amplifier.html) | China |
| L-Card | [link](https://en.lcard.ru/products/accesories/le-41) | Rusia |
<./biblio/references.bib>
## Bibliography {#bibliography}
<a id="orgaceef58"></a>Fleming, A.J. 2010. “Nanopositioning System with Force Feedback for High-Performance Tracking and Vibration Control.” _IEEE/ASME Transactions on Mechatronics_ 15 (3):43347. <https://doi.org/10.1109/tmech.2009.2028422>.
<a id="org683b96e"></a>Schmidt, R Munnig, Georg Schitter, and Adrian Rankers. 2014. _The Design of High Performance Mechatronics - 2nd Revised Edition_. Ios Press.

View File

@ -5,7 +5,7 @@ draft = false
+++
Tags
:
: [Cables]({{< relref "cables" >}})
## Manufacturers {#manufacturers}
@ -15,4 +15,13 @@ Tags
| LEMO | [link](https://www.lemo.com/en) | Switzerland |
| Fischer | [link](https://www.fischerconnectors.com/uk/en) | Switzerland |
## BNC {#bnc}
BNC connectors can have an impedance of 50Ohms or 75Ohms as shown in Figure [1](#org18575cd).
<a id="org18575cd"></a>
{{< figure src="/ox-hugo/bnc_50_75_ohms.jpg" caption="Figure 1: 75Ohms and 50Ohms BNC connectors" >}}
<./biblio/references.bib>

View File

@ -6,6 +6,7 @@ draft = false
Backlinks:
- [Signal Conditioner]({{< relref "signal_conditioner" >}})
- [Piezoelectric Actuators]({{< relref "piezoelectric_actuators" >}})
Tags
@ -38,9 +39,9 @@ Tags
The piezoelectric stack can be represented as a capacitance.
Let's take a capacitance driven by a voltage amplifier (Figure [1](#orgbf6bfad)).
Let's take a capacitance driven by a voltage amplifier (Figure [1](#org1213200)).
<a id="orgbf6bfad"></a>
<a id="org1213200"></a>
{{< figure src="/ox-hugo/voltage_amplifier_capacitance.png" caption="Figure 1: Piezoelectric actuator model with a voltage source" >}}
@ -60,7 +61,7 @@ Thus, for a specified maximum current \\(I\_\text{max}\\), the "power bandwidth"
- Above \\(\omega\_{0, \text{max}}\\), the maximum current \\(I\_\text{max}\\) is reached and the maximum voltage that can be applied decreases with frequency:
\\[ U\_\text{max} = \frac{I\_\text{max}}{\omega C} \\]
The maximum voltage as a function of frequency is shown in Figure [2](#org29f059d).
The maximum voltage as a function of frequency is shown in Figure [2](#org5c9f5fc).
```matlab
Vpkp = 170; % [V]
@ -74,7 +75,7 @@ C = 1e-6; % [F]
56.172
```
<a id="org29f059d"></a>
<a id="org5c9f5fc"></a>
{{< figure src="/ox-hugo/voltage_amplifier_max_V_piezo.png" caption="Figure 2: Maximum voltage as a function of the frequency for \\(C = 1 \mu F\\), \\(I\_\text{max} = 30mA\\) and \\(V\_{pkp} = 170 V\\)" >}}
@ -110,7 +111,7 @@ This can pose several problems:
### Noise {#noise}
Sources of noise in a system comprising a voltage amplifier and a capactive load are discussed in ([Spengen 2020](#orge9a57bd)).
Sources of noise in a system comprising a voltage amplifier and a capactive load are discussed in ([Spengen 2020](#org0688a0e)).
Proper enclosures and cabling are necessary to protect the system from capacitive and inductive interferance.
@ -122,13 +123,13 @@ The **input** impedance of voltage amplifiers are generally set to \\(50 \Omega\
The **output** (or internal) impedance of voltage amplifier is generally wanted small in order to have a small voltage drop when large current are drawn.
However, for stability reasons and to avoid overshoot (due to the internal negative feedback loop), this impedance can be chosen quite large.
This is discussed in ([Spengen 2017](#orge194af0)).
This is discussed in ([Spengen 2017](#orgfe834ca)).
## Bibliography {#bibliography}
<a id="org892a333"></a>Fleming, Andrew J., and Kam K. Leang. 2014. _Design, Modeling and Control of Nanopositioning Systems_. Advances in Industrial Control. Springer International Publishing. <https://doi.org/10.1007/978-3-319-06617-2>.
<a id="org624e57c"></a>Fleming, Andrew J., and Kam K. Leang. 2014. _Design, Modeling and Control of Nanopositioning Systems_. Advances in Industrial Control. Springer International Publishing. <https://doi.org/10.1007/978-3-319-06617-2>.
<a id="orge194af0"></a>Spengen, W. Merlijn van. 2017. “High Voltage Amplifiers and the Ubiquitous 50 Ohms: Caveats and Benefits.” Falco Systems.
<a id="orgfe834ca"></a>Spengen, W. Merlijn van. 2017. “High Voltage Amplifiers and the Ubiquitous 50 Ohms: Caveats and Benefits.” Falco Systems.
<a id="orge9a57bd"></a>———. 2020. “High Voltage Amplifiers: So You Think You Have Noise!” Falco Systems.
<a id="org0688a0e"></a>———. 2020. “High Voltage Amplifiers: So You Think You Have Noise!” Falco Systems.

Binary file not shown.

After

Width:  |  Height:  |  Size: 50 KiB

Binary file not shown.

After

Width:  |  Height:  |  Size: 56 KiB

Binary file not shown.

After

Width:  |  Height:  |  Size: 24 KiB