I want to build custom digital instrumentation for my race car. The mobile app isn't really adequate for my needs. The main problem is that I drive an open cockpit car, and mobile phone displays are impossible to read in direct sunlight.
The dash will likely be based on an Aruino uno, or stand-alone AVR micro-controller. I am envisioning several numeric displays for lap time, sensor values, warning lights, as well as a linear LED tachometer.
Where is the documentation for the Json protocol that the mobile app uses? I've looked through the firmware source code, but there doesn't seem to be any specification for the protocol. Failing that, is the source code for the mobile app available?
I'd rather avoid bluetooth if possible. Can you tell me more about the telemetry port interface?
Custom Digital Dashboard Project
Moderators: JeffC, rdoherty, stieg, brentp
Hi,
A dedicated mobile dash would be a great idea, and something we've discussed here as well.
We don't have the JSON protocol documented yet, but if you simply monitor the data coming off of the port (115200,8N1) you will be able to see the data format. You can use a computer to monitor the data stream to start.
Keep us posted on your progress!
A dedicated mobile dash would be a great idea, and something we've discussed here as well.
We don't have the JSON protocol documented yet, but if you simply monitor the data coming off of the port (115200,8N1) you will be able to see the data format. You can use a computer to monitor the data stream to start.
Keep us posted on your progress!
So, the "bluetooth" port is just a high-speed serial port? Where can I find the pin-outs?brentp wrote:Hi,
A dedicated mobile dash would be a great idea, and something we've discussed here as well.
We don't have the JSON protocol documented yet, but if you simply monitor the data coming off of the port (115200,8N1) you will be able to see the data format. You can use a computer to monitor the data stream to start.
Keep us posted on your progress!
Design Concepts
I spent a good portion of my Christmas vacation agonizing about the details. I had originally set out to hack together some kind of prototype, but my own skills are limited, and my handy friends were out of town. I figured I'd make a post on my thought process.
First, you need to understand the context. I plan to install this in a Spec Racer Ford. For those who don't know, I'm attaching some pictures of an SRF and its cockpit.
The key thing to note is that while it has a dashboard, it's quite a small one. It's also largely obscured by the wheel. There's room for one gauge directly behind the wheel, and there's room for two more on either side. None of these mounting locations are any good. They all require completely taking my eyes off the road to read any gauge.
My goal is to build a small unit that can be mounted just above the wheel and directly in my field of vision.
First, you need to understand the context. I plan to install this in a Spec Racer Ford. For those who don't know, I'm attaching some pictures of an SRF and its cockpit.
The key thing to note is that while it has a dashboard, it's quite a small one. It's also largely obscured by the wheel. There's room for one gauge directly behind the wheel, and there's room for two more on either side. None of these mounting locations are any good. They all require completely taking my eyes off the road to read any gauge.
My goal is to build a small unit that can be mounted just above the wheel and directly in my field of vision.
- Attachments
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- A Spec Racer Ford
- srf.jpg (25.31 KiB) Viewed 18757 times
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- Cockpit view with seat, wheel, and bodywork removed.
- cockpit_no_body.jpg (143.64 KiB) Viewed 18757 times
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- Cockpit view with bodywork and wheel installed.
- cockpit_redcar_body.jpg (237.31 KiB) Viewed 18757 times
Requirements
Physical Requirements
- all displays / indicators visible under direct sunlight
- can be mounted at desired height just above the steering wheel without obstructing my vision
- finish of unit should be not create unwanted reflections in driver's eyes
- no sharp edges or corners on unit or mounting hardware in case the thing comes off in a crash.
- does not interfere substantially with removal of the bodywork.
- weather-resistant enclosure
Functional Requirements
- Alarm indicators for most critical systems
- Alternator charge
- Low oil pressure
- Water temp
- AFR lean*
- Perhaps a few additional User-programmable alarms
- Shift / Overrun warning lights, and / or tachometer
- Lap time display (ideally Last, Best, and Predicted)
And idea I'm still toying with is that some of the alarm lights should be driven by hardware fed directly from the sensor inputs. I don't like the idea that a dodgy firmware update might prevent my oil light alarm from firing.
I'm attaching some concept drawings.
* I'm not sure that AFR readings are stable enough for an alarm to be useful.
- all displays / indicators visible under direct sunlight
- can be mounted at desired height just above the steering wheel without obstructing my vision
- finish of unit should be not create unwanted reflections in driver's eyes
- no sharp edges or corners on unit or mounting hardware in case the thing comes off in a crash.
- does not interfere substantially with removal of the bodywork.
- weather-resistant enclosure
Functional Requirements
- Alarm indicators for most critical systems
- Alternator charge
- Low oil pressure
- Water temp
- AFR lean*
- Perhaps a few additional User-programmable alarms
- Shift / Overrun warning lights, and / or tachometer
- Lap time display (ideally Last, Best, and Predicted)
And idea I'm still toying with is that some of the alarm lights should be driven by hardware fed directly from the sensor inputs. I don't like the idea that a dodgy firmware update might prevent my oil light alarm from firing.
I'm attaching some concept drawings.
* I'm not sure that AFR readings are stable enough for an alarm to be useful.
- Attachments
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- Fatter concept with bar tach
- 1387220511038.jpg (18.75 KiB) Viewed 18753 times
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- 7-Segment display lap time concept
- IMG_20131219_182544.jpg (61.72 KiB) Viewed 18753 times
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- Long, skinny concept
- 1387220053272.jpg (17.29 KiB) Viewed 18754 times
You could get yourself an Arduino and give something like this a try: https://www.sparkfun.com/products/710 It won't be the size you're looking for, but I don't know if you'll find something in the size you're looking for that doesn't cost a fortune. Another option for a screen would be something like this: http://www.amazon.com/SainSmart-Module- ... B003B22UR0
I know Autosport had shift lights as part of their perks for the Indiegogo campaign. They haven't shipped yet though, or at least mine hasn't.
I know Autosport had shift lights as part of their perks for the Indiegogo campaign. They haven't shipped yet though, or at least mine hasn't.
Lots of display options here:
http://www.adafruit.com/category/63
The RCPro Bluetooth app is really good, and has promise to get even better. I don't know if I want to buy a smallish tablet just for a virtual dash. Seems like an overpriced, overkill solution when there are all these cheap display options available. It's a matter of getting them to work with the RCPro........
http://www.adafruit.com/category/63
The RCPro Bluetooth app is really good, and has promise to get even better. I don't know if I want to buy a smallish tablet just for a virtual dash. Seems like an overpriced, overkill solution when there are all these cheap display options available. It's a matter of getting them to work with the RCPro........
I have some ideas to contribute for the layout of a dash - I'll try to post them here soon.
We really love real LEDs for displaying data, but the sheer versatility and sophistication of an app is undeniable. We'll support both, and we'll love to see ideas/implementations flowing out from the community as well.
We really love real LEDs for displaying data, but the sheer versatility and sophistication of an app is undeniable. We'll support both, and we'll love to see ideas/implementations flowing out from the community as well.
Ok, I broke out the whiteboard markers. Here's what I would imagine for a relatively simple dash. As you know, there are so many examples out there to draw from.
Captures essentially what you did, just a little bit more symmetry, and makes the current lap time and +/- delta time larger and more prominent. Arc of shift light LEDs at top; warning lights at the bottom. Switches at the side.
Just some very loose ideas
Captures essentially what you did, just a little bit more symmetry, and makes the current lap time and +/- delta time larger and more prominent. Arc of shift light LEDs at top; warning lights at the bottom. Switches at the side.
Just some very loose ideas
Update
I've done some experiments on this recently, and I found that the 7-segment displays on ada-fruit and sparkfun are nowhere near bright enough for direct sunlight unless you over-drive the crap out of them, though with a suitable dark filter, they can be made visible in indirect sunlight, but they definitely wash out with the sun directly on them.
So, I'm leaning back towards LCD for the numeric portion of the display. As ugly as I think they are, character displays are the easiest to work with. I'm going to try an experiment with one to see if it's legible at the required viewing distance. If that doesn't work, I'd lean towards a larger graphic LCD, even though this will definitely drive up the cost. My research indicates that a reflective TN type display is best for direct sunlight. A transflective TN display is the best compromise between low and high ambient light conditions. We never run at night, but we do sometimes run on overcast days, so that's a consideration. TFT is right out.
I bought some 5mm super-bright LEDs (3000 - 5000 mcd) in different colors. The viewing angle is rubbish, but they are definitely visible even in direct sunlight. I'm experimenting with different thicknesses of material for diffusing. It might not be necessary for what I'm doing, but I figure it couldn't hurt. Another option is to get some 10mm diffuse super-bright LEDs. I've found a few, but they only come in 50 count packages of a single color. Maybe there's room for some kind of group buy.
So, I'm leaning back towards LCD for the numeric portion of the display. As ugly as I think they are, character displays are the easiest to work with. I'm going to try an experiment with one to see if it's legible at the required viewing distance. If that doesn't work, I'd lean towards a larger graphic LCD, even though this will definitely drive up the cost. My research indicates that a reflective TN type display is best for direct sunlight. A transflective TN display is the best compromise between low and high ambient light conditions. We never run at night, but we do sometimes run on overcast days, so that's a consideration. TFT is right out.
I bought some 5mm super-bright LEDs (3000 - 5000 mcd) in different colors. The viewing angle is rubbish, but they are definitely visible even in direct sunlight. I'm experimenting with different thicknesses of material for diffusing. It might not be necessary for what I'm doing, but I figure it couldn't hurt. Another option is to get some 10mm diffuse super-bright LEDs. I've found a few, but they only come in 50 count packages of a single color. Maybe there's room for some kind of group buy.
What are the dots on the left?brentp wrote:Ok, I broke out the whiteboard markers. Here's what I would imagine for a relatively simple dash. As you know, there are so many examples out there to draw from.
Captures essentially what you did, just a little bit more symmetry, and makes the current lap time and +/- delta time larger and more prominent. Arc of shift light LEDs at top; warning lights at the bottom. Switches at the side.
Just some very loose ideas
I had a discussion with Dave, who maintains my car. He warned me about mounting gauges too high up in the slip stream. So, I've been re-thinking my design approach a bit. I decided to separate it into several components: The RCP itself, an interface module for connecting RCP to low impedance sensors, and the display unit(s).
I got a tech shop membership, and spent the weekend playing with Inventor. So, I've attached some renderings and cad files of a slim 4x1" light bar. This bar doesn't include any numeric displays, so it's pretty slim and can be mounted above the steering wheel and still stay out of the slip stream.
Definitely a work in progress. More of a learning exercise than a usable design. I'm just learning how to work with Inventor, so my abilities are somewhat limited at this point. I'm not crazy about the 9-pin D-sub connector. Maybe I'll have a cable emerge from the part, and put the connector somewhere down-stream. The connector only needs to be there if I end up mounting the part to the body, so that the bodywork can still be easily removed. If I mount to the dashboard plate, the light bar can stay in place.
The 5mm LEDs I have are water clear, and so the viewing angle is rubbish. They're nice and bright, but you have to look at them dead on. I am considering adding a diffuser. Based on my experiments with some 80% and 20% diffused, white polycarbonate, the diffuser would have to be pretty thin. I might also try scuffing the surface of an LED with sandpaper. On the other hand, I think it should be possible to get the viewing angle pretty much dead on.
I got a tech shop membership, and spent the weekend playing with Inventor. So, I've attached some renderings and cad files of a slim 4x1" light bar. This bar doesn't include any numeric displays, so it's pretty slim and can be mounted above the steering wheel and still stay out of the slip stream.
Definitely a work in progress. More of a learning exercise than a usable design. I'm just learning how to work with Inventor, so my abilities are somewhat limited at this point. I'm not crazy about the 9-pin D-sub connector. Maybe I'll have a cable emerge from the part, and put the connector somewhere down-stream. The connector only needs to be there if I end up mounting the part to the body, so that the bodywork can still be easily removed. If I mount to the dashboard plate, the light bar can stay in place.
The 5mm LEDs I have are water clear, and so the viewing angle is rubbish. They're nice and bright, but you have to look at them dead on. I am considering adding a diffuser. Based on my experiments with some 80% and 20% diffused, white polycarbonate, the diffuser would have to be pretty thin. I might also try scuffing the surface of an LED with sandpaper. On the other hand, I think it should be possible to get the viewing angle pretty much dead on.
- Attachments
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- Front view of the light bar
- rendering1.jpg (15.23 KiB) Viewed 18492 times
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- Rear view of the light bar
- rendering2.jpg (16.23 KiB) Viewed 18492 times
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- Mounting location
- cockpit_redcar_body.jpg (223.83 KiB) Viewed 18492 times
Check out the shift light Brent is working on. From the sounds of it you can use it as more than just a shift light.
https://www.facebook.com/pages/Autospor ... 4953614230
https://www.facebook.com/pages/Autospor ... 4953614230
That's pretty cool, though honestly I'm more excited about the sensors at this point.gizmodo wrote:Check out the shift light Brent is working on. From the sounds of it you can use it as more than just a shift light.
https://www.facebook.com/pages/Autospor ... 4953614230
Update
Finally got around to taking some base-line measurements of the dashboard and the clearance to the body work. I discovered, with mixed feelings, that the dash plate location is not fixed, but rather adjustable. It can move about half an inch side-to-side, 2 or three inchesforward and backward, and the angle can be adjusted. On the one hand, this means that I've got some wiggle room. On the other hand, this means I probably need to design an adjustable mounting system.
One issue right now is that I'm still waiting on my custom seat. Without the seat in the car, I can't check things like sight lines and whatnot. I really need a picture from eye level in *my* seating position.
I've also been shopping around for displays. I found a company that offers quite a few options, including some outdoor TFT type displays:
http://www.phoenixdisplay.com/transflective-display/
http://www.phoenixdisplay.com/graphic-display/
I would strongly prefer something low-profile, like this: http://www.phoenixdisplay.com/g-2406407c-va/
The nice thing about CAD software is that I can use their datasheet to model the product and visualize what a completed design would look like. That's probably what I'll be doing tonight.
In the mean time, though, I have some bits and pieces I can use to assemble a rough-draft prototype, which I plan to do this weekend. There are plenty of problems to solve that don't depend on being able to sit in the car, such as interfacing an arduino to the RCP's telemetry port, decoding the telemetry stream, designing hardware mount sensors for suspension throttle position, steering angle, and wheel speed, as well as configureing the RCP itself (which I have't bothered to do).
Anyways, things are progressing along in my head, at least.
One issue right now is that I'm still waiting on my custom seat. Without the seat in the car, I can't check things like sight lines and whatnot. I really need a picture from eye level in *my* seating position.
I've also been shopping around for displays. I found a company that offers quite a few options, including some outdoor TFT type displays:
http://www.phoenixdisplay.com/transflective-display/
http://www.phoenixdisplay.com/graphic-display/
I would strongly prefer something low-profile, like this: http://www.phoenixdisplay.com/g-2406407c-va/
The nice thing about CAD software is that I can use their datasheet to model the product and visualize what a completed design would look like. That's probably what I'll be doing tonight.
In the mean time, though, I have some bits and pieces I can use to assemble a rough-draft prototype, which I plan to do this weekend. There are plenty of problems to solve that don't depend on being able to sit in the car, such as interfacing an arduino to the RCP's telemetry port, decoding the telemetry stream, designing hardware mount sensors for suspension throttle position, steering angle, and wheel speed, as well as configureing the RCP itself (which I have't bothered to do).
Anyways, things are progressing along in my head, at least.