ArduPilot

@Yuri_Rage wrote: Background Due to the low cost and high flexibility of Espressif development boards, it’s very attractive to use them for a telemetry link, among ... [More] many other things. There is some existing software for ESP-based MAVLink telemetry, but I found it somewhat frustrating. I have had very little success with DroneBridge, even after following the documentation closely. I also tried Tridge’s fork of mavesp8266 with little success. I think Tridge’s mavesp8266 fork is quite promising, and I do not intend to replace or supplant it in any way, I’m just offering my own (likely somewhat “caveman”) solution to the problem at hand. DroneBridge, on the other hand, seems a bit bloated for the intended purpose and offers no way to operate in station mode, but only as an access point, which does not fit my use case. My apologies if my criticism is taken negatively by its developers. In fairness, I forked the project, made an attempt at bending it to my will…and failed, mostly due to my unfamiliarity with the build environment. Concept Because of my success relaying MAVLink messages using ser2net on a Raspberry Pi, which simply repeats serial traffic over a network connection without regard for message content, I thought it should be possible to use an ESP board to do similar. Both DroneBridge and mavesp8266 parse MAVLink messages prior to forwarding them, which seems an unnecessary processing and memory burden. Testing shows that an ESP32 clocked at 240MHz can process a simple serial repeater loop in less than 3μs, which means that even at 921600 baud, the loop will complete in less time than it takes for an 8-N-1 byte to be transmitted, meaning that the ESP32 can process a serial message byte-by-byte without loss, if necessary. ESP WiFi Serial Bridge In any case, I was motivated to attempt my own solution set, and I first achieved success with an ESP32 and this serial bridge code, forked from another example. Testing the bridge with an ESP8266 proved unreliable, perhaps because of the way its UARTs are configured in hardware, so I recommend using an ESP32. It simply creates an access point or connects to an existing network and relays serial traffic on a TCP port. You’ll need to modify config.h to suit your application and then compile, build, and upload using the Arduino IDE. While I’m sure the Espressif IDE is more capable, I find the Arduino IDE more friendly for small projects like this, and I’ve been frustrated more than once when using the Espressif one. Moving Forward with ESP-Now I was dissatisfied with the range using the built-in antenna, and before I started cutting traces or ordering hardware for an external antenna modification, I stumbled on Espressif’s ESP-Now feature for ESP32 and ESP8266 platforms. If you are unfamiliar, ESP-Now is a peer-to-peer 2.4GHz protocol allowing Espressif WiFi boards to communicate directly with one another at a fairly low power state and at longer ranges than the usual WiFi connection (without as much overhead). ESP-Now is somewhat weakly documented, and the online examples are sometimes a bit dated, as the libraries have changed since some of the example code was written. I found this bi-directional example which seemed most up to date and worked from there. The author of that example, Rui Santos, posted this video describing ESP-Now. I arrived at this sketch, which shows zero packet loss at short range, and has offered ~25m range with brick walls obstructing the signal. Outdoor testing showed a reliable range of ~115m with direct line of sight, though ANY minor obstruction causes signal loss when using the built-in antennas beyond ~50m. A range test with these external antennas got ~50m through brick/obstacles and 430m outdoors in direct line-of-sight (and farther is probably achievable, since I couldn’t really get much farther away than that and maintain direct line-of-sight where I was testing). All testing was done at 57600 baud, though it should be possible to use much faster serial transmission rates. OF NOTE: There is a 250 byte limit for ESP-Now packet transmission, where MAVLink defines a maximum packet size of 263 bytes. In practice, most MAVLink messages are much shorter than that, and I have not discovered a case where information is lost under the latest Rover 4.2.0-dev firmware. I have not yet done the homework to determine which MAVLink messages exceed 250 bytes (I suspect few to none). I think it’s important to realize, though, that this ESP-Now bridge may result in data loss when large packets are transmitted, and it should likely not be considered for critical applications. I did not include the libraries/definitions for ESP8266 compatibility in the ESP-Now code, though it would likely be trivial to do so if one were so motivated. TLDR; I modified an ESP-based WiFi serial bridge you can use for MAVLink.. and then I wrote an ESP-Now serial bridge for increased range at the expense of using another ESP board. Post Script If you’re interested in adding an external antenna to your ESP development board, the following should get you pointed in the right direction. There are MANY variations of these boards, so use caution when cutting traces and soldering components based on these pictures alone - your board may differ significantly. There are some boards with antenna connectors already present if you don’t want to go to this trouble and/or potentially ruin your board. The onboard antenna is located here, and the portion of it we are going to modify is under the tweezers - the two traces leading away from the exposed dots just left of the tweezer tips. image4800×600 123 KB Cut the traces as shown, scoring somewhat deeply with a razor blade to ensure the circuit is permanently broken. You want to cut the two short sections that are vertically oriented in this picture. image3800×600 148 KB Carefully use a razor blade to scrape the solder mask away, exposing the bare copper traces here. It doesn’t take much pressure, and you could easily damage the traces, so go easy. image2800×600 168 KB Tin the traces and component leads, and carefully solder the connector like this. Note, in this orientation, the bottom trace is ground, and the top trace is signal (center pin). You could also solder a length of small coaxial cable or a different style connector in a similar fashion. These SMA connectors have appropriate pin spacing for the job. image1800×600 140 KB You don’t want to rely on the thin copper traces and solder joint as the only mechanical support for the connector, so add some hot glue or dielectric epoxy to provide some additional strength/strain relief. Use care when screwing an antenna onto the board - hold the entire connector rather than relying on the solder joint and glue. image0800×600 136 KB Posts: 3 Participants: 2 Read full topic [Less]

Background Due to the low cost and high flexibility of Espressif development boards, it’s very attractive to use them for a telemetry link, among many other things. There is some existing ... [More] software for ESP-based MAVLink telemetry, but I found it somewhat frustrating. I have had very little success with DroneBridge, even after following the documentation closely. I also tried Tridge’s fork of mavesp8266 with little success. I think Tridge’s mavesp8266 fork is quite promising, and I do not intend to replace or supplant it in any way, I’m just offering my own (likely somewhat “caveman”) solution to the problem at hand. DroneBridge, on the other hand, seems a bit bloated for the intended purpose and offers no way to operate in station mode, but only as an access point, which does not fit my use case. My apologies if my criticism is taken negatively by its developers. In fairness, I forked the project, made an attempt at bending it to my will…and failed, mostly due to my unfamiliarity with the build environment. Concept Because of my success relaying MAVLink messages using ser2net on a Raspberry Pi, which simply repeats serial traffic over a network connection without regard for message content, I thought it should be possible to use an ESP board to do similar. Both DroneBridge and mavesp8266 parse MAVLink messages prior to forwarding them, which seems an unnecessary processing and memory burden. Testing shows that an ESP32 clocked at 240MHz can process a simple serial repeater loop in less than 3μs, which means that even at 921600 baud, the loop will complete in less time than it takes for an 8-N-1 byte to be transmitted, meaning that the ESP32 can process a serial message byte-by-byte without loss, if necessary. ESP WiFi Serial Bridge In any case, I was motivated to attempt my own solution set, and I first achieved success with an ESP32 and this serial bridge code, forked from another example. Testing the bridge with an ESP8266 proved unreliable, perhaps because of the way its UARTs are configured in hardware, so I recommend using an ESP32. It simply creates an access point or connects to an existing network and relays serial traffic on a TCP port. You’ll need to modify config.h to suit your application and then compile, build, and upload using the Arduino IDE. While I’m sure the Espressif IDE is more capable, I find the Arduino IDE more friendly for small projects like this, and I’ve been frustrated more than once when using the Espressif one. Moving Forward with ESP-Now I was dissatisfied with the range using the built-in antenna, and before I started cutting traces or ordering hardware for an external antenna modification, I stumbled on Espressif’s ESP-Now feature for ESP32 and ESP8266 platforms. If you are unfamiliar, ESP-Now is a peer-to-peer 2.4GHz protocol allowing Espressif WiFi boards to communicate directly with one another at a fairly low power state and at longer ranges than the usual WiFi connection (without as much overhead). ESP-Now is somewhat weakly documented, and the online examples are sometimes a bit dated, as the libraries have changed since some of the example code was written. I found this bi-directional example which seemed most up to date and worked from there. The author of that example, Rui Santos, posted this video describing ESP-Now. I arrived at this sketch, which shows zero packet loss at short range, and has offered ~25m range with brick walls obstructing the signal. Outdoor testing showed a reliable range of ~115m with direct line of sight, though ANY minor obstruction causes signal loss when using the built-in antennas beyond ~50m. A range test with these external antennas got ~50m through brick/obstacles and 430m outdoors in direct line-of-sight (and farther is probably achievable, since I couldn’t really get much farther away than that and maintain direct line-of-sight where I was testing). All testing was done at 57600 baud, though it should be possible to use much faster serial transmission rates. OF NOTE: There is a 250 byte limit for ESP-Now packet transmission, where MAVLink defines a maximum packet size of 263 bytes. In practice, most MAVLink messages are much shorter than that, and I have not discovered a case where information is lost under the latest Rover 4.2.0-dev firmware. I have not yet done the homework to determine which MAVLink messages exceed 250 bytes (I suspect few to none). I think it’s important to realize, though, that this ESP-Now bridge may result in data loss when large packets are transmitted, and it should likely not be considered for critical applications. I did not include the libraries/definitions for ESP8266 compatibility in the ESP-Now code, though it would likely be trivial to do so if one were so motivated. TLDR; I modified an ESP-based WiFi serial bridge you can use for MAVLink.. and then I wrote an ESP-Now serial bridge for increased range at the expense of using another ESP board. Post Script If you’re interested in adding an external antenna to your ESP development board, the following should get you pointed in the right direction. There are MANY variations of these boards, so use caution when cutting traces and soldering components based on these pictures alone - your board may differ significantly. There are some boards with antenna connectors already present if you don’t want to go to this trouble and/or potentially ruin your board. The onboard antenna is located here, and the portion of it we are going to modify is under the tweezers - the two traces leading away from the exposed dots just left of the tweezer tips. Cut the traces as shown, scoring somewhat deeply with a razor blade to ensure the circuit is permanently broken. You want to cut the two short sections that are vertically oriented in this picture. Carefully use a razor blade to scrape the solder mask away, exposing the bare copper traces here. It doesn’t take much pressure, and you could easily damage the traces, so go easy. Tin the traces and component leads, and carefully solder the connector like this. Note, in this orientation, the bottom trace is ground, and the top trace is signal (center pin). You could also solder a length of small coaxial cable or a different style connector in a similar fashion. These SMA connectors have appropriate pin spacing for the job. You don’t want to rely on the thin copper traces and solder joint as the only mechanical support for the connector, so add some hot glue or dielectric epoxy to provide some additional strength/strain relief. Use care when screwing an antenna onto the board - hold the entire connector rather than relying on the solder joint and glue. 3 posts - 2 participants Read full topic [Less]

Background Due to the low cost and high flexibility of Espressif development boards, it’s very attractive to use them for a telemetry link, among many other things. There is some existing ... [More] software for ESP-based MAVLink telemetry, but I found it somewhat frustrating. I have had very little success with DroneBridge, even after following the documentation closely. I also tried Tridge’s fork of mavesp8266 with little success. I think Tridge’s mavesp8266 fork is quite promising, and I do not intend to replace or supplant it in any way, I’m just offering my own (likely somewhat “caveman”) solution to the problem at hand. DroneBridge, on the other hand, seems a bit bloated for the intended purpose and offers no way to operate in station mode, but only as an access point, which does not fit my use case. My apologies if my criticism is taken negatively by its developers. In fairness, I forked the project, made an attempt at bending it to my will…and failed, mostly due to my unfamiliarity with the build environment. Concept Because of my success relaying MAVLink messages using ser2net on a Raspberry Pi, which simply repeats serial traffic over a network connection without regard for message content, I thought it should be possible to use an ESP board to do similar. Both DroneBridge and mavesp8266 parse MAVLink messages prior to forwarding them, which seems an unnecessary processing and memory burden. Testing shows that an ESP32 clocked at 240MHz can process a simple serial repeater loop in less than 3μs, which means that even at 921600 baud, the loop will complete in less time than it takes for an 8-N-1 byte to be transmitted, meaning that the ESP32 can process a serial message byte-by-byte without loss, if necessary. ESP WiFi Serial Bridge In any case, I was motivated to attempt my own solution set, and I first achieved success with an ESP32 and this serial bridge code, forked from another example. Testing the bridge with an ESP8266 proved unreliable, perhaps because of the way its UARTs are configured in hardware, so I recommend using an ESP32. It simply creates an access point or connects to an existing network and relays serial traffic on a TCP port. You’ll need to modify config.h to suit your application and then compile, build, and upload using the Arduino IDE. While I’m sure the Espressif IDE is more capable, I find the Arduino IDE more friendly for small projects like this, and I’ve been frustrated more than once when using the Espressif one. Moving Forward with ESP-Now I was dissatisfied with the range using the built-in antenna, and before I started cutting traces or ordering hardware for an external antenna modification, I stumbled on Espressif’s ESP-Now feature for ESP32 and ESP8266 platforms. If you are unfamiliar, ESP-Now is a peer-to-peer 2.4GHz protocol allowing Espressif WiFi boards to communicate directly with one another at a fairly low power state and at longer ranges than the usual WiFi connection (without as much overhead). ESP-Now is somewhat weakly documented, and the online examples are sometimes a bit dated, as the libraries have changed since some of the example code was written. I found this bi-directional example which seemed most up to date and worked from there. The author of that example, Rui Santos, posted this video describing ESP-Now. I arrived at this sketch, which shows zero packet loss at short range, and has offered ~25m range with brick walls obstructing the signal. Outdoor testing showed a reliable range of ~115m with direct line of sight, though ANY minor obstruction causes signal loss when using the built-in antennas beyond ~50m. A range test with these external antennas got ~50m through brick/obstacles and 430m outdoors in direct line-of-sight (and farther is probably achievable, since I couldn’t really get much farther away than that and maintain direct line-of-sight where I was testing). All testing was done at 57600 baud, though it should be possible to use much faster serial transmission rates. OF NOTE: There is a 250 byte limit for ESP-Now packet transmission, where MAVLink defines a maximum packet size of 263 bytes. In practice, most MAVLink messages are much shorter than that, and I have not discovered a case where information is lost under the latest Rover 4.2.0-dev firmware. I have not yet done the homework to determine which MAVLink messages exceed 250 bytes (I suspect few to none). I think it’s important to realize, though, that this ESP-Now bridge may result in data loss when large packets are transmitted, and it should likely not be considered for critical applications. I did not include the libraries/definitions for ESP8266 compatibility in the ESP-Now code, though it would likely be trivial to do so if one were so motivated. TLDR; I modified an ESP-based WiFi serial bridge you can use for MAVLink.. and then I wrote an ESP-Now serial bridge for increased range at the expense of using another ESP board. Post Script If you’re interested in adding an external antenna to your ESP development board, the following should get you pointed in the right direction. There are MANY variations of these boards, so use caution when cutting traces and soldering components based on these pictures alone - your board may differ significantly. There are some boards with antenna connectors already present if you don’t want to go to this trouble and/or potentially ruin your board. The onboard antenna is located here, and the portion of it we are going to modify is under the tweezers - the two traces leading away from the exposed dots just left of the tweezer tips. Cut the traces as shown, scoring somewhat deeply with a razor blade to ensure the circuit is permanently broken. You want to cut the two short sections that are vertically oriented in this picture. Carefully use a razor blade to scrape the solder mask away, exposing the bare copper traces here. It doesn’t take much pressure, and you could easily damage the traces, so go easy. Tin the traces and component leads, and carefully solder the connector like this. Note, in this orientation, the bottom trace is ground, and the top trace is signal (center pin). You could also solder a length of small coaxial cable or a different style connector in a similar fashion. These SMA connectors have appropriate pin spacing for the job. You don’t want to rely on the thin copper traces and solder joint as the only mechanical support for the connector, so add some hot glue or dielectric epoxy to provide some additional strength/strain relief. Use care when screwing an antenna onto the board - hold the entire connector rather than relying on the solder joint and glue. 20 posts - 6 participants Read full topic [Less]

Background Due to the low cost and high flexibility of Espressif development boards, it’s very attractive to use them for a telemetry link, among many other things. There is some existing ... [More] software for ESP-based MAVLink telemetry, but I found it somewhat frustrating. I have had very little success with DroneBridge, even after following the documentation closely. I also tried Tridge’s fork of mavesp8266 with little success. I think Tridge’s mavesp8266 fork is quite promising, and I do not intend to replace or supplant it in any way, I’m just offering my own (likely somewhat “caveman”) solution to the problem at hand. DroneBridge, on the other hand, seems a bit bloated for the intended purpose and offers no way to operate in station mode, but only as an access point, which does not fit my use case. My apologies if my criticism is taken negatively by its developers. In fairness, I forked the project, made an attempt at bending it to my will…and failed, mostly due to my unfamiliarity with the build environment. Concept Because of my success relaying MAVLink messages using ser2net on a Raspberry Pi, which simply repeats serial traffic over a network connection without regard for message content, I thought it should be possible to use an ESP board to do similar. Both DroneBridge and mavesp8266 parse MAVLink messages prior to forwarding them, which seems an unnecessary processing and memory burden. Testing shows that an ESP32 clocked at 240MHz can process a simple serial repeater loop in less than 3μs, which means that even at 921600 baud, the loop will complete in less time than it takes for an 8-N-1 byte to be transmitted, meaning that the ESP32 can process a serial message byte-by-byte without loss, if necessary. ESP WiFi Serial Bridge In any case, I was motivated to attempt my own solution set, and I first achieved success with an ESP32 and this serial bridge code, forked from another example. Testing the bridge with an ESP8266 proved unreliable, perhaps because of the way its UARTs are configured in hardware, so I recommend using an ESP32. It simply creates an access point or connects to an existing network and relays serial traffic on a TCP port. You’ll need to modify config.h to suit your application and then compile, build, and upload using the Arduino IDE. While I’m sure the Espressif IDE is more capable, I find the Arduino IDE more friendly for small projects like this, and I’ve been frustrated more than once when using the Espressif one. Moving Forward with ESP-Now I was dissatisfied with the range using the built-in antenna, and before I started cutting traces or ordering hardware for an external antenna modification, I stumbled on Espressif’s ESP-Now feature for ESP32 and ESP8266 platforms. If you are unfamiliar, ESP-Now is a peer-to-peer 2.4GHz protocol allowing Espressif WiFi boards to communicate directly with one another at a fairly low power state and at longer ranges than the usual WiFi connection (without as much overhead). ESP-Now is somewhat weakly documented, and the online examples are sometimes a bit dated, as the libraries have changed since some of the example code was written. I found this bi-directional example which seemed most up to date and worked from there. The author of that example, Rui Santos, posted this video describing ESP-Now. I arrived at this sketch, which shows zero packet loss at short range, and has offered ~25m range with brick walls obstructing the signal. Outdoor testing showed a reliable range of ~115m with direct line of sight, though ANY minor obstruction causes signal loss when using the built-in antennas beyond ~50m. A range test with these external antennas got ~50m through brick/obstacles and 430m outdoors in direct line-of-sight (and farther is probably achievable, since I couldn’t really get much farther away than that and maintain direct line-of-sight where I was testing). All testing was done at 57600 baud, though it should be possible to use much faster serial transmission rates. OF NOTE: There is a 250 byte limit for ESP-Now packet transmission, where MAVLink defines a maximum packet size of 263 bytes. In practice, most MAVLink messages are much shorter than that, and I have not discovered a case where information is lost under the latest Rover 4.2.0-dev firmware. I have not yet done the homework to determine which MAVLink messages exceed 250 bytes (I suspect few to none). I think it’s important to realize, though, that this ESP-Now bridge may result in data loss when large packets are transmitted, and it should likely not be considered for critical applications. I did not include the libraries/definitions for ESP8266 compatibility in the ESP-Now code, though it would likely be trivial to do so if one were so motivated. TLDR; I modified an ESP-based WiFi serial bridge you can use for MAVLink.. and then I wrote an ESP-Now serial bridge for increased range at the expense of using another ESP board. Post Script If you’re interested in adding an external antenna to your ESP development board, the following should get you pointed in the right direction. There are MANY variations of these boards, so use caution when cutting traces and soldering components based on these pictures alone - your board may differ significantly. There are some boards with antenna connectors already present if you don’t want to go to this trouble and/or potentially ruin your board. The onboard antenna is located here, and the portion of it we are going to modify is under the tweezers - the two traces leading away from the exposed dots just left of the tweezer tips. Cut the traces as shown, scoring somewhat deeply with a razor blade to ensure the circuit is permanently broken. You want to cut the two short sections that are vertically oriented in this picture. Carefully use a razor blade to scrape the solder mask away, exposing the bare copper traces here. It doesn’t take much pressure, and you could easily damage the traces, so go easy. Tin the traces and component leads, and carefully solder the connector like this. Note, in this orientation, the bottom trace is ground, and the top trace is signal (center pin). You could also solder a length of small coaxial cable or a different style connector in a similar fashion. These SMA connectors have appropriate pin spacing for the job. You don’t want to rely on the thin copper traces and solder joint as the only mechanical support for the connector, so add some hot glue or dielectric epoxy to provide some additional strength/strain relief. Use care when screwing an antenna onto the board - hold the entire connector rather than relying on the solder joint and glue. 11 posts - 4 participants Read full topic [Less]

Background Due to the low cost and high flexibility of Espressif development boards, it’s very attractive to use them for a telemetry link, among many other things. There is some existing ... [More] software for ESP-based MAVLink telemetry, but I found it somewhat frustrating. I have had very little success with DroneBridge, even after following the documentation closely. I also tried Tridge’s fork of mavesp8266 with little success. I think Tridge’s mavesp8266 fork is quite promising, and I do not intend to replace or supplant it in any way, I’m just offering my own (likely somewhat “caveman”) solution to the problem at hand. DroneBridge, on the other hand, seems a bit bloated for the intended purpose and offers no way to operate in station mode, but only as an access point, which does not fit my use case. My apologies if my criticism is taken negatively by its developers. In fairness, I forked the project, made an attempt at bending it to my will…and failed, mostly due to my unfamiliarity with the build environment. Concept Because of my success relaying MAVLink messages using ser2net on a Raspberry Pi, which simply repeats serial traffic over a network connection without regard for message content, I thought it should be possible to use an ESP board to do similar. Both DroneBridge and mavesp8266 parse MAVLink messages prior to forwarding them, which seems an unnecessary processing and memory burden. Testing shows that an ESP32 clocked at 240MHz can process a simple serial repeater loop in less than 3μs, which means that even at 921600 baud, the loop will complete in less time than it takes for an 8-N-1 byte to be transmitted, meaning that the ESP32 can process a serial message byte-by-byte without loss, if necessary. ESP WiFi Serial Bridge In any case, I was motivated to attempt my own solution set, and I first achieved success with an ESP32 and this serial bridge code, forked from another example. Testing the bridge with an ESP8266 proved unreliable, perhaps because of the way its UARTs are configured in hardware, so I recommend using an ESP32. It simply creates an access point or connects to an existing network and relays serial traffic on a TCP port. You’ll need to modify config.h to suit your application and then compile, build, and upload using the Arduino IDE. While I’m sure the Espressif IDE is more capable, I find the Arduino IDE more friendly for small projects like this, and I’ve been frustrated more than once when using the Espressif one. Moving Forward with ESP-Now I was dissatisfied with the range using the built-in antenna, and before I started cutting traces or ordering hardware for an external antenna modification, I stumbled on Espressif’s ESP-Now feature for ESP32 and ESP8266 platforms. If you are unfamiliar, ESP-Now is a peer-to-peer 2.4GHz protocol allowing Espressif WiFi boards to communicate directly with one another at a fairly low power state and at longer ranges than the usual WiFi connection (without as much overhead). ESP-Now is somewhat weakly documented, and the online examples are sometimes a bit dated, as the libraries have changed since some of the example code was written. I found this bi-directional example which seemed most up to date and worked from there. The author of that example, Rui Santos, posted this video describing ESP-Now. I arrived at this sketch, which shows zero packet loss at short range, and has offered ~25m range with brick walls obstructing the signal. Outdoor testing showed a reliable range of ~115m with direct line of sight, though ANY minor obstruction causes signal loss when using the built-in antennas beyond ~50m. A range test with these external antennas got ~50m through brick/obstacles and 430m outdoors in direct line-of-sight (and farther is probably achievable, since I couldn’t really get much farther away than that and maintain direct line-of-sight where I was testing). All testing was done at 57600 baud, though it should be possible to use much faster serial transmission rates. OF NOTE: There is a 250 byte limit for ESP-Now packet transmission, where MAVLink defines a maximum packet size of 263 bytes. In practice, most MAVLink messages are much shorter than that, and I have not discovered a case where information is lost under the latest Rover 4.2.0-dev firmware. I have not yet done the homework to determine which MAVLink messages exceed 250 bytes (I suspect few to none). I think it’s important to realize, though, that this ESP-Now bridge may result in data loss when large packets are transmitted, and it should likely not be considered for critical applications. I did not include the libraries/definitions for ESP8266 compatibility in the ESP-Now code, though it would likely be trivial to do so if one were so motivated. TLDR; I modified an ESP-based WiFi serial bridge you can use for MAVLink.. and then I wrote an ESP-Now serial bridge for increased range at the expense of using another ESP board. Post Script If you’re interested in adding an external antenna to your ESP development board, the following should get you pointed in the right direction. There are MANY variations of these boards, so use caution when cutting traces and soldering components based on these pictures alone - your board may differ significantly. There are some boards with antenna connectors already present if you don’t want to go to this trouble and/or potentially ruin your board. The onboard antenna is located here, and the portion of it we are going to modify is under the tweezers - the two traces leading away from the exposed dots just left of the tweezer tips. Cut the traces as shown, scoring somewhat deeply with a razor blade to ensure the circuit is permanently broken. You want to cut the two short sections that are vertically oriented in this picture. Carefully use a razor blade to scrape the solder mask away, exposing the bare copper traces here. It doesn’t take much pressure, and you could easily damage the traces, so go easy. Tin the traces and component leads, and carefully solder the connector like this. Note, in this orientation, the bottom trace is ground, and the top trace is signal (center pin). You could also solder a length of small coaxial cable or a different style connector in a similar fashion. These SMA connectors have appropriate pin spacing for the job. You don’t want to rely on the thin copper traces and solder joint as the only mechanical support for the connector, so add some hot glue or dielectric epoxy to provide some additional strength/strain relief. Use care when screwing an antenna onto the board - hold the entire connector rather than relying on the solder joint and glue. 7 posts - 4 participants Read full topic [Less]

Despite having worked on drones for 10+ years I only recently learned of the existance of “ideal diodes” and how useful they are on vehicles that require multiple batteries so I thought I’d share in case others have also not heard of ... [More] them. Technically speaking an ideal diode is just a regular diode in that it only allows electricity to flow in one direction but what makes it special is that the forward voltage drop is extremely low. In a quick test I did on the ideal diodes shown above (provided to me by Running Electronics) the drop was something like 0.01V. These particular ideal diodes can also handle relatively large current (I hear 100 Amps at 25V) which makes them very useful for vehicles which require a lot of batteries like the 100km DeSET mapping boat that I’m working on with AttracLab, Lighthouse and Shimane University. We estimate the vehicle will require 2 or 3 kWh of batteries to travel 100km so we plan on using 6x Panasonic NKY580B02 e-bike batteries (each is 16Ah, 6S). Without an ideal diode you would probably need to be very careful that the voltage of all 6 batteries was the same or else current from higher voltage batteries would flow (through the + terminal wires) to the lower voltage batteries which could potentially be quite dangerous. Keeping two battery’s voltages the same is manageable but with six it becomes far too easy to make a mistake. In this setup, each battery has a little extension wire with the ideal diode included to protect against any back flow. A side note though is that it may be that these particular e-bike batteries already have ideal diodes built in. They certainly have short circuit protection which is another extremely important safety feature when you’re dealing with batteries of this size. Components on this boat include: Cube Gold (same as CubeOrange) Herelink (recently certified for use in Japan) dAISy AIS sensor Torqeedo 1003c motor 6x Panasonic NKY580B02 e-bike batteries Panaonsic e-bike USB adapters modified to allow each battery to be connected using XT90 connectors I will be providing further updates on this boat including videos once we’ve made more progress testing. 17 posts - 6 participants Read full topic [Less]

@rmackay9 wrote: ideal-diode1065×1489 426 KB Despite having worked on drones for 10+ years I only recently learned of the existance of “ideal diodes” and how useful they are on vehicles that require ... [More] multiple batteries so I thought I’d share in case others have also not heard of them. Technically speaking an ideal diode is just a regular diode in that it only allows electricity to flow in one direction but what makes it special is that the forward voltage drop is extremely low. In a quick test I did on the ideal diodes shown above (provided to me by Running Electronics) the drop was something like 0.01V. These particular ideal diodes can also handle relatively large current (I hear 100 Amps at 25V) which makes them very useful for vehicles which require a lot of batteries like the 100km DeSET mapping boat that I’m working on with AttracLab, Lighthouse and Shimane University. boat1-small1504×846 297 KB We estimate the vehicle will require 2 or 3 kWh of batteries to travel 100km so we plan on using 6x Panasonic NKY580B02 e-bike batteries (each is 16Ah, 6S). ideal-diodes-six-batteries-small816×612 139 KB Without an ideal diode you would probably need to be very careful that the voltage of all 6 batteries was the same or else current from higher voltage batteries would flow (through the + terminal wires) to the lower voltage batteries which could potentially be quite dangerous. Keeping two battery’s voltages the same is manageable but with six it becomes far too easy to make a mistake. In this setup, each battery has a little extension wire with the ideal diode included to protect against any back flow. A side note though is that it may be that these particular e-bike batteries already have ideal diodes built in. They certainly have short circuit protection which is another extremely important safety feature when you’re dealing with batteries of this size. Components on this boat include: Cube Gold (same as CubeOrange) Herelink (recently certified for use in Japan) dAISy AIS sensor Torqeedo 1003c motor 6x Panasonic NKY580B02 e-bike batteries Panaonsic e-bike USB adapters modified to allow each battery to be connected using XT90 connectors I will be providing further updates on this boat including videos once we’ve made more progress testing. Posts: 9 Participants: 4 Read full topic [Less]

Despite having worked on drones for 10+ years I only recently learned of the existance of “ideal diodes” and how useful they are on vehicles that require multiple batteries so I thought I’d share in case others have also not heard of ... [More] them. Technically speaking an ideal diode is just a regular diode in that it only allows electricity to flow in one direction but what makes it special is that the forward voltage drop is extremely low. In a quick test I did on the ideal diodes shown above (provided to me by Running Electronics) the drop was something like 0.01V. These particular ideal diodes can also handle relatively large current (I hear 100 Amps at 25V) which makes them very useful for vehicles which require a lot of batteries like the 100km DeSET mapping boat that I’m working on with AttracLab, Lighthouse and Shimane University. We estimate the vehicle will require 2 or 3 kWh of batteries to travel 100km so we plan on using 6x Panasonic NKY580B02 e-bike batteries (each is 16Ah, 6S). Without an ideal diode you would probably need to be very careful that the voltage of all 6 batteries was the same or else current from higher voltage batteries would flow (through the + terminal wires) to the lower voltage batteries which could potentially be quite dangerous. Keeping two battery’s voltages the same is manageable but with six it becomes far too easy to make a mistake. In this setup, each battery has a little extension wire with the ideal diode included to protect against any back flow. A side note though is that it may be that these particular e-bike batteries already have ideal diodes built in. They certainly have short circuit protection which is another extremely important safety feature when you’re dealing with batteries of this size. Components on this boat include: Cube Gold (same as CubeOrange) Herelink (recently certified for use in Japan) dAISy AIS sensor Torqeedo 1003c motor 6x Panasonic NKY580B02 e-bike batteries Panaonsic e-bike USB adapters modified to allow each battery to be connected using XT90 connectors I will be providing further updates on this boat including videos once we’ve made more progress testing. 26 posts - 6 participants Read full topic [Less]

Despite having worked on drones for 10+ years I only recently learned of the existance of “ideal diodes” and how useful they are on vehicles that require multiple batteries so I thought I’d share in case others have also not heard of ... [More] them. Technically speaking an ideal diode is just a regular diode in that it only allows electricity to flow in one direction but what makes it special is that the forward voltage drop is extremely low. In a quick test I did on the ideal diodes shown above (provided to me by Running Electronics) the drop was something like 0.01V. These particular ideal diodes can also handle relatively large current (I hear 100 Amps at 25V) which makes them very useful for vehicles which require a lot of batteries like the 100km DeSET mapping boat that I’m working on with AttracLab, Lighthouse and Shimane University. We estimate the vehicle will require 2 or 3 kWh of batteries to travel 100km so we plan on using 6x Panasonic NKY580B02 e-bike batteries (each is 16Ah, 6S). Without an ideal diode you would probably need to be very careful that the voltage of all 6 batteries was the same or else current from higher voltage batteries would flow (through the + terminal wires) to the lower voltage batteries which could potentially be quite dangerous. Keeping two battery’s voltages the same is manageable but with six it becomes far too easy to make a mistake. In this setup, each battery has a little extension wire with the ideal diode included to protect against any back flow. A side note though is that it may be that these particular e-bike batteries already have ideal diodes built in. They certainly have short circuit protection which is another extremely important safety feature when you’re dealing with batteries of this size. Components on this boat include: Cube Gold (same as CubeOrange) Herelink (recently certified for use in Japan) dAISy AIS sensor Torqeedo 1003c motor 6x Panasonic NKY580B02 e-bike batteries Panaonsic e-bike USB adapters modified to allow each battery to be connected using XT90 connectors I will be providing further updates on this boat including videos once we’ve made more progress testing. 9 posts - 4 participants Read full topic [Less]

Despite having worked on drones for 10+ years I only recently learned of the existance of “ideal diodes” and how useful they are on vehicles that require multiple batteries so I thought I’d share in case others have also not heard of ... [More] them. Technically speaking an ideal diode is just a regular diode in that it only allows electricity to flow in one direction but what makes it special is that the forward voltage drop is extremely low. In a quick test I did on the ideal diodes shown above (provided to me by Running Electronics) the drop was something like 0.01V. These particular ideal diodes can also handle relatively large current (I hear 100 Amps at 25V) which makes them very useful for vehicles which require a lot of batteries like the 100km DeSET mapping boat that I’m working on with AttracLab, Lighthouse and Shimane University. We estimate the vehicle will require 2 or 3 kWh of batteries to travel 100km so we plan on using 6x Panasonic NKY580B02 e-bike batteries (each is 16Ah, 6S). Without an ideal diode you would probably need to be very careful that the voltage of all 6 batteries was the same or else current from higher voltage batteries would flow (through the + terminal wires) to the lower voltage batteries which could potentially be quite dangerous. Keeping two battery’s voltages the same is manageable but with six it becomes far too easy to make a mistake. In this setup, each battery has a little extension wire with the ideal diode included to protect against any back flow. A side note though is that it may be that these particular e-bike batteries already have ideal diodes built in. They certainly have short circuit protection which is another extremely important safety feature when you’re dealing with batteries of this size. Components on this boat include: Cube Gold (same as CubeOrange) Herelink (recently certified for use in Japan) dAISy AIS sensor Torqeedo 1003c motor 6x Panasonic NKY580B02 e-bike batteries Panaonsic e-bike USB adapters modified to allow each battery to be connected using XT90 connectors I will be providing further updates on this boat including videos once we’ve made more progress testing. 32 posts - 9 participants Read full topic [Less]