Proof of Attendance

The average theater goer walks into a performance with their ticket stub freshly procured from the box office. An usher hands them a playbill as they find their seat. Both items unique to the time and place of the event, and available only to those physically in attendance at the performance, these forms of memorabilia offer audiences collectible, tangible tokens to commemorate an arts experience. However, common practice in the digital age is to take a picture of the stage from one’s seat with playbill in hand to post on social media and store in the cloud, transforming a physical token of memorabilia into a digital one. Today, we mark our in-person attendance with digital memories, finding opportunities to bridge ephemeral experiences with the longevity and security of our digital, online presence.

Proof of Attendance Protocols (POAP’s, pronounced poh-ap) seek to bridge the divide between in-person experiences and our digital presence through Non-fungible Token (NFT) badges that can only be collected by those who attend an event. Each badge is unique and records the owner’s attendance at an event on the blockchain, serving as irrefutable proof of attendance. They are collectible by design in the same way that a playbill, ticket stub, or concert t-shirt are, but without the risk of the collectible being lost or damaged. Their scarcity incentivizes attendance and collectability and provides those in attendance with evidence of their involvement in a community.

While POAPs originated in Ethereum communities, they are being increasingly used by mainstream organizations as a way to engage audiences and foster community across the digital-physical divide. At this year’s SXSW conference, Fox Entertainment’s new NFT studio Blockchain Creative Labs rewarded participants with POAPs at several venues throughout the festival, incentivizing attendees to go to each location to collect the whole set. Doodle, an NFT collective, partnered with Behr paint at their SXSW activation to distribute POAPs to participants that featured artwork and new paint swatches from the companies’ collaboration. In April, Warner Music Group, the third largest recording company in the music industry, inked a deal with the startup behind POAPs to create exclusive drops for concert goers and to connect artists directly with their fans.

Between the environmental impact of NFTs, the volatility of crypto currency, and the reproducibility of the digital image, the rise of NFTs in our zeitgeist is accompanied by necessary discourse. However, POAPs pose a unique use-case for these digital assets for event holders and goers alike. So, are POAPs another NFT gimmick, or a legitimate way to engage audiences across the digital-physical divide?

POAPs, Blockchain, and NFTs

POAPs were originally developed for ETHDenver 2019, an Ethereum conference and hackathon that served to showcase the capabilities of the Ethereum cryptocurrency and blockchain technology at large. The creator of POAPs, Gonzalo Sainz Trápaga, sought to create a standardized, accessible, secure, and free way for event organizers to distribute digital badges to attendees using the unique properties of blockchain and NFTs. He created POAP Inc. as a centralized platform for issuers and collectors to create and mint NFT badges using his open-source infrastructure.

POAPs are NFTs created and minted using a smart contract on the blockchain, managed by POAP Inc. to record specific event and ownership data (for an in-depth overview on this technology, read through this AMT Lab deep dive). In short, blockchain is a way to store information in a way that is almost impossible to alter or remove by using Distributed Ledger Technology (DLT). When an NFT is minted on the blockchain, ownership and transaction information is recorded using DLT. The ledger records this data in a way that is nearly immutable by using a “proof-of-stake” verification system. This means that even if a POAP is bought, sold, or transferred, proof of the original owner and the event is irrefutable through the ledger’s recording.

POAP’s smart contract mints NFT badges as standard ERC-721 tokens, the standard for all NFTs. The main characteristic for this type of token is that each one is unique and gives the holder ownership rights to the token. This standard guarantees that these NFT digital tokens are unique to the time and place of the event they were created for, and that they are unique to the owner of the POAP. Unlike most NFTs, POAPs are minted using the Gnosis Chain (formerly the xDai chain). This Ethereum-based sidechain uses a unique proof-of-stake mechanism that verifies transactions on a bridge chain. This makes transactions faster and inexpensive by avoiding high Ethereum gas prices and congestion. Minting NFTs on the Gnosis Chain is far more energy efficient than Bitcoin or Ethereum 1.0, mitigating the environmental impact of minting these NFTs. This also allows POAPs to be free for everyone to engage with, issuers and collectors alike, as the fees to mint POAPs as NFTs are so minimal that the company picks up the tab.

How do they work?

While POAPs are unique in how they utilize blockchain technology, neither the issuer nor the collector needs a crypto wallet to create and collect POAPs, although it is required to mint POAPs as NFTS and engage with the full range of benefits that POAPs can offer.

POAPs can be created and issued to event attendees using POAP Inc’s official platform for either in-person or digital events. Issuers fill out a form on POAP’s website to “create a drop”, which requires the issuer to provide event details including the time and place of the event, what the POAP will commemorate, how they will be distributed, how many will be issued, along with a file of the POAP’s design, and the issuer’s email address. Once the image is approved for distribution and clears the organization’s guidelines, the issuer receives an email with unique links for collectors to claim their digital badge.

Collectors can reserve POAPs through this unique link on POAPs platform. This link can be distributed to attendees directly through the email address they provide the organization upon event registration, by airdropping a link at the event, or using QR codes on-site. From this link, collectors only need to provide their email address to reserve their POAP and start or add to their collection. By connecting a crypto wallet to POAP Inc’s platform, collectors can mint the POAP as an NFT. Otherwise, POAPs can be collected and stored on the platform and on the app tied to the collector’s email address.

The process to issue and collect POAPs requires minimal effort by both parties, making them logistically easy to integrate into an event. Additionally, issuing and collecting POAPs requires minimal Personally Identifiable Information (PII) be shared with the company. Nothing more than an email address or Ethereum wallet is required by the company to issue or collect tokens, mitigating the risk of personal data being leaked.

Use Cases

At their core, POAPs were developed to bring communities together to celebrate a special, shared memory. Beyond collectability, POAPs can be used to engage audiences through a range of activities, live or digital, during or after an event takes place.

POAP tokens can be used to provide holders with exclusive access to community forums or events. This can range from Discord channel invitations to metaverse event access and VIP parties that connect members of a community together. POAP.vote allows issuers to create polls for POAP token holders, organized so that only those with unique links tied to an event can participate. Raffles can be held using POAP.fun where one eligible POAP gives collectors one raffle ticket entry. This can be used by event organizers to hold raffles with real-world or digital prizes to event attendees. Issuers can also connect to collectors through airdrops and can send event attendees discount codes or pre-sale merch links.

Still in Beta, POAP.art is the newest initiative by POAP that sits at “the intersection of art and tech.” This extension provides eligible POAP owners with a shared, interactive canvas where community members can participate in “paint parties”. During a select timeframe, community members can select one pixel color per second to create a collective work of art with other POAP holders. Canvases range in size, upwards of 4096×4096 pixels. After the paint party ends, the artwork is minted as an NFT for the community.

A crypto wallet is needed to participate – specifically a non-hardware connected MetaMask wallet – as well as an eligible POAP which can be obtained through a public POAP-claim process. Currently, this initiative is only hosted by POAP and is free for the public to participate in. But if this activation is anything like POAP’s other initiatives, it will soon be available for issuers to develop for their own private communities.

Conclusion

Memorabilia serves as a way to bookmark and catalog life events. While attendees at in-person events have traditional opportunities to collect memorabilia, like saving ticket stubs or taking photos of themselves at the event, memorabilia is more difficult to provide digital event-goers. With the rise of digital events due to the COVID-19 pandemic, POAPs give event coordinators an opportunity to distribute meaningful, unique memorabilia to these attendees. These collectible digital tokens serve as a means to display these bookmarks and encourage event attendance and participation. Coupled with interactive, community-oriented activities, POAPs as memorabilia deepen audience engagement and elevate experiences.

POAPs utilize blockchain and NFTs in unique ways while mitigating some of their drawbacks. However, collecting and displaying these tokens is most meaningful if the collector and their community are already interested and involved with digital communities. The attributes of POAPs are more aligned with what makes tangible collectibles so special, but they fall short when the collections are difficult to openly display and share. Given the growing ubiquity of Web3.0 and the increasingly active online presence of individuals and communities, POAPs pose a potential use case for NFTs to help foster community as event coordinators navigate this changing event landscape.

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Dance relies on the audience’s sense of sight to experience a performance. However, dancing itself is a very tactile experience. A dancer’s precise movements depend on a heightened internal awareness of the body – how joints are stacked and what muscles are activated. They must also maintain an awareness of external forces – how one limb moves in relation to the other, how their skin feels sliding against the floor, and where they sense other dancers moving with them in space.

The experience of the audience is vastly different from that of the dancer. So is there a way to bridge this divide and communicate a multisensory experience to the audience, and allow those who cannot see, to feel? Tapping into this sense of touch might help audiences experience dance in a whole new way.

The word haptic derives from the Greek word “touch”. Simply put, haptics is the coordination of touch, perception, and action. Together, our skin, musculoskeletal system, and nervous system communicate information to our brains about the outside world we experience. These systems work together to make up our haptic sense. Although one could classify any communication received via a tactile sensation as haptic feedback, it is most often used today regarding haptic technology that simulates the human touch experience.

Haptic feedback is becoming more common in everyday technology as a communication tool between the device and the end-user. Apple is certainly a fan, with Macbook force touch trackpads providing haptic communication for various degrees of force, or the Apple Watch sending communication via haptic “bumps” to user’s wrists to tell them the time. Video game controllers are famous for their Dual Shock haptic feedback, rumbling the entire device during an intense boss battle. In newer, more sophisticated controllers, haptic feedback creates the sensation of a joystick beneath the player’s thumb by using precise vibrations.

How does it work?

Haptic feedback relies on two systems to engage the haptic sense – one on the human side and one on the machine side. Each requires an input, a translation, and an output.

On the human side, a finger’s skin cells make contact with a haptic feedback device and receive an input. This alerts the finger’s tactile sensor nerves which send whatever information it just received from the cells to the brain. The brain translates this information and neuron synapses fire a call to action to the body. This output might be a sudden jerk if the haptic feedback is programmed to feel sharp, or its denseness may make for curious fingers to explore the larger shape.

A similar process happens on the machine side. Haptic feedback sensors receive an input, either data that has been programmed or some external force, and send it to a computer. The computer then translates this data as commands to actuators, the machine’s device that produces motion. Based on the data it receives, it outputs specific vibration frequencies, too high pitched for the human ear, to exert different levels of force, motion, and sensation.

In this way, haptic feedback can simulate touch and trick the brain into firing neuron synapses that make us think we are experiencing a surface different than how it appears to exist in the real world. Our haptic sense is incredibly sensitive and can detect and perceive thousands of surface textures, an object’s directional motion, velocity, and temperature. This sense is so delicate, that one spike from a single touch receptor neuron is enough to elicit conscious recognition in the brain. This allows for precise applications of haptic feedback to simulate texture and 3D objects.

All of this to say, the tactile experience is profound and felt deeply throughout the human ecosystem. Touch often elicits an emotional response, too, allowing a carefully crafted gesture to have a visceral impact. Haptic feedback is uniquely suited to serve as a reinterpretation of dance. Both occur in three-dimensional space, depending on variations in force and motion to communicate with an audience. Using haptic feedback to translate dance enables choreographers to communicate nonverbally to multiple senses and gives those who cannot experience the visual performance an alternative interpretation that can still be moving and engaging.  

Haptic feedback technology is wide spanning, but dance applications are primarily focused around surface haptics and vibrotactile haptics. Unlike surface haptics, like the Macbook’s trackpad, vibrotactile haptics do not require a precise input from the user through a surface to elicit feedback. Instead, data, like recorded choreography or live dance, can be fed to the haptic technology’s computer to determine the haptic feedback without requiring direct contact with the end-user. This allows haptic feedback technology to remain stationary in a space or sit fixed on the body like a wearable. 

Choreography and Hapitc Feedback

The Choreo-haptic project out of the University of Edinburgh uses surface haptics, having audience members rest their palms on haptic pads in order to experience dance. A Microsoft Kinect captures movement input in real-time, tracking dance’s movement throughout a space. This information is sent to an Arduino processor in the haptic pad, translating data to commands and activating a 5×6 motor board. Vibrotactile haptic feedback communicates different movement qualities and patterns as they occur.

The Microsoft Kinect captures an abstraction of the movement being performed. To communicate the quality of the movement, an algorithm breaks down the dynamism of a body and translates it into an intensity value which is signaled back to the haptic device. The algorithm, developed to translate movement to haptic feedback, takes note of motion patterns, spatial movements, the body’s depth in space, where the center of mass is placed, and the position of particular limbs. It has the ability to capture which part of the body is moving, the tempo and timing, and a movement’s effect on the body posture.

The more a movement affects body posture, the more intense the haptic feedback output will be. Each of these qualities is assigned different intensities, motions, and rhythms to replicate the most noticeable aspects of a live-performed dance.

Because the setup is relatively inexpensive and easily programmable, it is best used as a choreographic medium to understand what movements are best experienced through haptic feedback for visually impaired audiences. While this device gives dancers a greater range of motion and freedom, it is at the cost of a more detailed haptic experience for the audience. Abstractions in choreography allow only the large, grand movements to be communicated to the visually impaired audience member, while the small movements, which are often the most vital in dance expression, are lost.

Haptic Cushion

The Dance Haptics project sought to create a multisensory experience for dance audiences, especially those that are visually impaired, by translating dance movements to haptic feedback. To make this accessible in theatre spaces, the team designed the haptic device as a seat back cushion to provide haptic feedback to the audience member’s back in a way that can be easily integrated into existing performance spaces and would not encumber the audience.

The haptic cushion is composed of 64 vibrotactile actuators arranged on an 8×8 grid. An Arduino board inside the cushion serves as the device’s computer to translate input data to the actuators. A dance performance choreographed for a proportionally sized 8×8 grid provides input for the haptic feedback.

To record the input and translate dance to haptics, a dance is recorded via a motion capture system overhead. While the top-down information communicates floor patterns across the audience’s back, vertical cameras capture movement qualities on the vertical plane. Using the audio track from the performance, along with the overhead floor plan, the haptic cushion can translate more detailed physical action to physical sensation.

The haptic cushion can be used with a prerecorded “haptic track” while a live performance occurs, or it can be fed movement information during a live performance.  With a bigger surface area than most haptic feedback devices used in the field, the haptic cushion provides the most visceral sensory experience and feels the closest to feeling a dance performed throughout the body. The haptic cushion’s engaging interpretation of dance translation embedded in a theater-friendly device could radically change an audience member’s experience.

This technology is limited by the necessity to choreograph for the device, both in terms of movement qualities that translate to haptic feedback best and spatial constraints of the 8×8 grid. The vast majority of works today would need to be adapted in some way to be experienced through the haptic cushion. This application is best suited for dance on film projects that could be widely distributed as a standalone piece or be played in tandem with a haptic track in a theater space.

Conclusion

No technology will be able to identically replicate human touch or exactly recreate the tactile experience of dancing. There is potential in these cases, however, to communicate dance in new ways, more accessible and immersive for audiences.

The demand for multisensory experiences is increasing, given the rise of immersive art and theatre in our post-lockdown world. Audiences have a desire to experience more deeply, which often means with more than one sense. Multiple interpretations of a nonverbal art form give choreographers the opportunity to communicate artistic expression through an entirely different medium that engages a wider population. For visually impaired audiences, including haptic feedback in dance performance is a critical next step in accessibility for the dance medium.

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