Ghid de Cablare#

De ce contează cablarea?#

Have you ever looked inside your robot and thought „what a mess of wires”? Wiring is extremely important in FTC®, but is often overlooked or hastily done the hour before competition starts. However, time spent in wiring the robot properly is crucial to the performance and maintenance of the robot.

Atenție

Nu este recomandat ca echipele să treacă cu vederea cablarea, dar multe echipe noi par să nu țină cont de acest lucru sau să se gândească prea puțin la cablarea corectă a robotului.

Deși obositoare și adesea deloc plăcute, cablurile pot face diferența dintre o victorie și o pierdere. Cel mai bun robot din lume nu va putea funcționa dacă un fir este slăbit sau se încurcă în mijlocul unui meci. Astfel, este obligatoriu ca cablarea să fie gândită în mod intenționat atunci când se proiectează și se construiește un robot.

FIRST® Ghid de Cablare FTC#

FIRST® has created a wiring guide to help teams with tasks like crimping cables, soldering connections, and ESD mitigation that won’t be covered in this guide. Once you read up on electronics and wiring here, look at the FTC Wiring Guide for the best practices and more tips & tricks. In addition, FIRST has written an ESD Mitigation Whitepaper that is worth taking a look at.

Sfaturi Generale#

Întotdeauna etichetați firele! Când sunt adunate la un loc este posibil sa nu știti ce fir intră în ce port.
Legați firele libere și, mai bine, legați acele fire de o componentă structurală. Acest lucru va asigură că firele nu interferează cu mecanismele voastre.
Atenție la numărul de porturi! Adesea, hub-ul REV va avea mai multe porturi pentru fiecare conector de pe hub-ul REV. REV are un ghid de pinout pentru a evita confuzia.
Tratați fiecare conexiune de cabluri ca pe un punct de defecțiune. Prin urmare, folosiți bandă adezivă electrică pentru a lipi și izola conexiunile și reduceți cât mai mult posibil tensionarea cablurilor.
Strain relief should be used everywhere possible. It is highly recommended for teams to use products like the REV USB Retention Mount, as well as 3D printing strain relief methods for devices such as the Expansion Hub and robot controller phones.
** NU sudați un fir înainte de a-l prinde**. Sudura se poate „strecura” și este posibilă pierderea conexiunii, ceea ce poate duce la incendiu.
Păstrați toate firele cât mai scurte posibil pentru a preveni încurcarea și pentru a îmbunătăți gestionarea firelor.
Când folosiți cabluri de date/senzor, țineți-le departe de motoare. Acest lucru va reduce interferențele electromagnetice (EMI). Adăugați o perlă de ferită dacă este posibil.
Conectorii sertizați sunt, în general, mai buni decât conectorii sudați, deoarece îmbinările prin lipire se pot defecta mai ușor decât o conexiune strânsă.
** Țineți firele la distanță de mecanismele în mișcare** și asigurați-vă că nu există riscul ca un mecanism să agațe un fir. Aceasta este o aplicare adecvată a unor materiale precum acrilicul, care permit driver-ilor să vadă în interiorul robotului, păstrând în același timp firele la distanță față de alți roboți/piese de joc. Se recomandă ca echipele să achiziționeze legături detașabile din velcro sau coliere de cablu pentru a ajuta la gestionarea cablurilor.
Pentru firele de alimentare, sunt de preferat firele de :termen:`calibru<Gauge>` mai mic (dimensiuni mai mari). Aceasta înseamnă o rezistență mai mică pe fir și o putere mai mare de trecere. Totuși, acest lucru este neglijabil pentru firele de date.
Small wires and cables are fragile. Treat them as such, and don’t put them in an area where they will constantly be hit by another object. Larger power cables can take much more abuse.
Asigură-te că firele sunt ținute departe de punctele de ciupire, unde un alt mecanism ar putea duce firul în contact. Acest lucru este deosebit de important în cazul brațelor sau al mecanismelor care sunt articulate.

Un exemplu de cablare slabă — Exemplu prost de cablare!#

An example of good wiring by 8417 — Good example of wiring by 8417 «Lectric Legends#

An example of good wiring by 7244 — Good example of wiring by 7244 Out of the Box Robotics#

When wiring, also take the time to plan out a specific layout for your wires and how they will run throughout the robot. Take the time to lay out something like an electronics panel if necessary! When building the robot, devote adequate space to wiring. This could mean mounting a PVC pipe and running wires from the back end of the robot through it, or simply using velcro or zipties.

Sfat

Make sure that wires are as short as possible to reduce the risk of entanglement.

However, as components move out of the robot, the wires move with it. Tying down every loose inch will result in wire disconnecting. Wiring is the art of finding the perfect balance between shortest length and allowing enough freedom as mechanisms need.

It is also recommended for electronics to be mounted on a nonconductive material such as wood to prevent ESD.

An example of good wiring on a non-conductive surface by 3736 — 3736 Serious Business#

Specific Recommendations#

Module Power#

Be aware, XT30 connectors can wear out significantly faster than PowerPole connectors. Additionally, because XT30 connectors are soldered, they can break much easier than PowerPole connections.

Cabling for module power should be at least 14awg, if not 12awg. Keep in mind that it must be stranded, not solid, wire.

Motor Power#

Cabling for motor power should be between 16awg and 12awg. Again, stranded, not solid, wire.

Some motors (like the REV HD Hex and Core Hex) will have removable power connectors on the back, while other motors (like the Andymark NeveRests) will have a cable permanently soldered on the back. It is much more convenient to have a connector on the back, or failing that, have a very short plug on the back of the motor. Once your wires are run and secured, taking them out won’t be fun.

Servo Wires#

Using heavy-duty extension wires are recommended.

Tape the connections between extension wires and servo wires with electrical tape. This is as the connections can become loose over time and are easy to pull out.

The VEX Motor Controller 29 has the wrong gender connector on the 3-pin end. You are required to either use an adapter cable, or add the right connector to the wires (recommended). Be sure to protect the MC29, as it is fragile and prone to failure if it takes impact from another object.

USB#

USB is generally a strong connector, but is prone to wearing out over time. Refrain from plugging/unplugging these cables more than necessary, especially on the RC/DS phones.

USB loves strain relief. To keep disconnects low, tie down cables to leave as little loose cabling on the robot as possible.

Sensor Wires/Encoder Wires#

Sensor wires and their connectors can be incredibly fragile. Use caution when routing, and keep slack on the connector end when adding strain relief to the cable.

The JST data connectors on the REV Expansion Hub and Control Hub have +5v, GND, and two data pins. If you are using a digital or analog sensor that does not use I2C, you can use a Y cable that gives two sensors off of one port.

Miscellaneous#

REV Grounding Strap

The REV Grounding Strap is currently the only legal way to ground your robot. Attach the end to the metal part of your robot frame, and plug the XT30 connector end into a free XT30 port on your robot.

Power distribution blocks/panels

The REV Power Distribution Block allows teams to have more than four XT30 connectors (2 on each Expansion Hub). The block can be connected to the Servo Power Module to boost voltage for servos.

Dryer sheets

Dryer sheets can be used to wipe down the robot after every match in order to reduce static buildup. This is not directly recommended by FIRST or any vendor, but our empirical evidence throughout the years suggests that it helps, or at the very least, can’t hurt to do so. However, dryer sheets may or may not be on the boundary of legality, as grounding the robot to the ground is illegal.

Staticide/static spray

Staticide is a spray that helps to keep static off of the robot. Please be sure to spray your robot before an event and not during the event.

Common causes of static

Every single contact point of your robot to the floor will increase the amount of static buildup.
Too much turning scrub (or traction when wheels try to turn). This is possible if a 4WD or 6WD (no center drop) with all traction wheels is used.
A conductive part dragging along the ground. For example, try not to have an intake touch the ground when the robot is moving as much as possible. Foam wheels and foam rollers are a common culprit.